# Dolmar 7900 Big Bore Kit Review



## blsnelling (Dec 2, 2008)

I've got a saw to install it on now, so it's time for the details of the prototype BB Kit I have here. Bore size is 54mm resulting in a displacement of 85cc, up from 79cc stock. So far I've visually inspected, measured specs, and taken pictures. I've not yet put the parts on my saw. That will come soon enough. The P&C look very good. I intend for this is to be a fair honest report. *Please keep this thread clean and on topic* as I would like for it to be something of a product review than can be useful to others.

Here's some of the specs.

Piston Weight = 2.8 oz
Wrist Pin Weight = 0.6 oz
Cylinder Weight = 20.8 oz
Crown thickness above top ring groove = 0.130". Plenty of room for a popup.
Ring thickness = 0.047" = 1.2mm
Ring end-gap = 0.008"
Piston to cylinder clearance = 0.0025"

Here are some notes I've made so far.

There is one small knick in the cylinder wall well below the exhaust port. It's very small and will hurt nothing. The NiSi is not damaged.
Stihl style circlips are now used and the piston is relieve likewise for removal. A nice improvement the customers have called for.
The ports are very nicely beveled.
The NiSi coating and honing looks nice.
The piston skirt does not even come close to freeporting the exhaust port at TDC. 
There is room for widening the ports, but not as much as with the 361 kit. Should be enough for modest gains.


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## blsnelling (Dec 2, 2008)




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## spacemule (Dec 2, 2008)

Brad, I like your pictures--on topic and in focus. I'm curious though--is someone supplying you with these kits for the purpose of evaluation, or are these purchases of your own initiative?


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## blsnelling (Dec 2, 2008)

These are prototypes for the purposes of evaluation. They will not be on the market for probably at least a couple more months.


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## stihl only (Dec 2, 2008)

Could the knick be from poor packaging of the wrist pin? Have seen that on some kits.


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## JONSEREDFAN6069 (Dec 2, 2008)

let me know how it works out, I have a 7900 will this fit on it?


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## spacemule (Dec 2, 2008)

blsnelling said:


> These are prototypes for the purposes of evaluation. They will not be on the market for probably at least a couple more months.



Cool. Does that mean there is still room for constructive criticism and suggestions to be implemented?


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## scotclayshooter (Dec 2, 2008)

Looks like a lot of scope for lightening the piston.


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## scotclayshooter (Dec 2, 2008)

Whats the CCs going to be?
Doh read it twice and didnt notice 85CC


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## blsnelling (Dec 2, 2008)

spacemule said:


> Cool. Does that mean there is still room for constructive criticism and suggestions to be implemented?



Shoot away. I'm sure they're watching the response. I was not asked to post my findings but your comments will be seen by those that care.


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## davefr (Dec 2, 2008)

Who's the manufacturer? 

Past posts indicate that BB kits have a somewhat tainted reputation in delivering any real gains. Is this one believed to be different?

P.S. Great images!!


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## blsnelling (Dec 2, 2008)

I have only installed one BB kit in the past, an 066. It was a 2nd or 3rd gen kit. It was stronger out of the box than my ported 066 Red Light. I'm fixing to port another 1st gen 066 jug to put on a 064, so we'll see how it compares again. 

Unfortuantely, I do not have a stock 7900 here to compare it to. If we have a GTG in the next couple of months, it should still be stock and we can compare them then.


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## blsnelling (Dec 2, 2008)

davefr said:


> Who's the manufacturer?



These are from Baileys as all of the BB kits are.


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## Jacob J. (Dec 2, 2008)

Combustion chamber looks good- smaller than other big bore kits. Good job Bailey's.


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## Saw Dr. (Dec 2, 2008)

Hmmm, Wasn't Brad looking for a 441? I wonder what else is in the works for a BB kit.....


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## blsnelling (Dec 2, 2008)

B200Driver said:


> Hmmm, Wasn't Brad looking for a 441? I wonder what else is in the works for a BB kit.....



There is a 441. I didn't take one since I wasn't real optimistic in scoring a cheap 441. If you have a beater to sell, I can get the kit and test it. That's the only other one.


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## davefr (Dec 2, 2008)

blsnelling said:


> These are from Baileys as all of the BB kits are.



Yes, but who's the actual manufacturer? Is it from a major manufacturer or some no name sweat shop in China?


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## blsnelling (Dec 2, 2008)

davefr said:


> Yes, but who's the actual manufacturer? Is it from a major manufacturer or some no name sweat shop in China?



I have no idea.


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## Saw Dr. (Dec 2, 2008)

davefr said:


> Yes, but who's the actual manufacturer? Is it from a major manufacturer or some no name sweat shop in China?



If it works well, what's the difference. People do it all of the time with cars, appliances, electronics, etc.....

Sorry, Brad. I'll quit bogging your thread down.


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## Austin1 (Dec 2, 2008)

blsnelling said:


> These are prototypes for the purposes of evaluation. They will not be on the market for probably at least a couple more months.


That's great to hear, I don't think anyone could pull off a fair evaluation of a product more than you!I like reading your post as they are fair . +1 hope I have rep left.


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## toddstreeservic (Dec 2, 2008)

opcorn:


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## 4mocajuns (Dec 2, 2008)

Any idea on what the cost of these things will be? It would be sweet if it were a cheaper alternative to putting a stock 7900 P&C on my 6401!


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## mattmc2003 (Dec 2, 2008)

4mocajuns said:


> Any idea on what the cost of these things will be? It would be sweet if it were a cheaper alternative to putting a stock 7900 P&C on my 6401!



:agree2:


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## husky455rancher (Dec 2, 2008)

+1 on that i been scrounging the home depots one day ill get one that has a saw for sale. if the bb was close to the overpriced 80cc kit im sure it would be a huge seller.


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## blsnelling (Dec 2, 2008)

I've heard nothing on price. I would expect it to be inline with the price of the other BB kits they sells.


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## Former Saw Builder (Dec 2, 2008)

*7900 BB Kit*

I to am interested in these kits I have been custom building the Makita 6401 saws for quite awhile now with great results. I would love to get my hands on one of those kits to see how they compair to the 7900 top ends.

Below is a few pictures of the saws I've been pumping out. They have alot going on under the hood. I'm looking forward to seeing your results. 

 

http://www.ritcheys.net/makita/001.jpg
http://www.ritcheys.net/makita/002.jpg
http://www.ritcheys.net/makita/003.jpg
http://www.ritcheys.net/makita/004.jpg
http://www.ritcheys.net/makita/005.jpg


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## gink595 (Dec 2, 2008)

blsnelling said:


> Unfortuantely, I do not have a stock 7900 here to compare it to. If we have a GTG in the next couple of months, it should still be stock and we can compare them then.



Brad there is another Indiana GTG in mid Januaray in Attica. I would bring my stocker 7900 down, it isn't broke in yet, it might be a fair comparison for ya. I'd llike to see the difference, though I'm completely happy with the power of that 7900.


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## blsnelling (Dec 2, 2008)

This 6401 was absolutely nasty under the covers. They must wash them when they come back in. The outside looks ok but that's about it. It's currently down to the cases and most everything in the dishwasher. I left the 64cc jug on and capped off the intake and exhaust. It'll probably be Thursday before I get to put it together.

I'm off to search to see how this muffler's put together. The inner baffle tube looks to have a large exit into the muffler body. If there are no additional baffles, all I need to do is open the factory exit or add a second on the other side and use a Husky deflector.


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## Four Paws (Dec 2, 2008)

blsnelling said:


> These are prototypes for the purposes of evaluation. They will not be on the market for probably at least a couple more months.



How do you rank?


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## Andyshine77 (Dec 2, 2008)

You're correct, the inner baffle doesn't really need any work, just open up the cover.


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## Metals406 (Dec 2, 2008)

Four Paws said:


> How do you rank?



He is Brad... Of the Clan Snellerizer.


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## blsnelling (Dec 2, 2008)

Four Paws said:


> How do you rank?



E-4 Specialist when discharged


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## blsnelling (Dec 2, 2008)

Andyshine77 said:


> You're correct, the inner baffle doesn't really need any work, just open up the cover.



Know of any pics of the muffler opened up? Is there anything inside the muffler beside the center tube?


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## jra1100 (Dec 3, 2008)

*I assume*

That this will work on the 6401 also, since they are for the most part the same thing, right? From what I see in the pictures the workmanshop seem very good.

Ed, WOW, that saw looks beautiful, great work. JR


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## Andyshine77 (Dec 3, 2008)

blsnelling said:


> Know of any pics of the muffler opened up? Is there anything inside the muffler beside the center tube?



Nothing else in the muffler, just the baffle cage, and the tubes for the mounting screws. Sorry I can't find any pics.


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## blsnelling (Dec 3, 2008)

I'm nuts. I stayed up and put this thing together. Squish with the original gasket was 0.037". I removed it for a squish of 0.019". I had the same issues with skirt clearance as I did with the 361BB. All I had to do was round off the corners and it was a go. It fired right up and ran well. I pulled a hot compression check and it was nearly 160. While I had the plug out I took a look in the cylinder and saw a scratch. I could just feel it with the tip of a screwdriver dragging across it. So off came the jug. There was one scratch just to the loeft of the exhaust port and one smaller one over by the transfers. There is absolutely not damage to the piston at all. All I can figure is that there was something on my ring compressor and got in the cylinder. I found nothing while I was in there. I took oiled 400 grit sandpaper and polished the scratches. I don't think anything was really hurt. It's back together and running good.

What is throttle response like on a 7900? Is it lightening quick like a 361, or a hair sluggish right off idle? It has respectible throttle response, but not like the 361. 















These are the scratches before I polished them.








These are after I polished.









Whatever this coating is, it wears off quickly. I noticed the same thing on my 066BB.


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## blsnelling (Dec 3, 2008)

I've got a spare part and have not looked at the IPL yet. Where does it go?


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## windthrown (Dec 3, 2008)

Is that one of those piston support blocks?


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## scotclayshooter (Dec 3, 2008)

blsnelling said:


> Know of any pics of the muffler opened up? Is there anything inside the muffler beside the center tube?


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## Andyshine77 (Dec 3, 2008)

blsnelling said:


> I've got a spare part and have not looked at the IPL yet. Where does it go?



It's the top cover grommet for the ignition wire. Stock compression on a 7900 is 170-180. I must say don't like the looks of that piston ring. The throttle response should be quick, maybe not as quick as a 361, but close.


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## brages (Dec 3, 2008)

Is a scratch like that in the cylinder no big deal? I cleaned up my MS290 cylinder and have about six or seven scratches that look like that.


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## davefr (Dec 3, 2008)

blsnelling said:


> Know of any pics of the muffler opened up? Is there anything inside the muffler beside the center tube?



Your wish is my command. This is how I did mine. (I knew Husquvarna parts were good for something!!):
http://www.arboristsite.com/showthread.php?t=75018&highlight=dolmar+dual+port+muffler


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## blsnelling (Dec 3, 2008)

Andyshine77 said:


> It's the top cover grommet for the ignition wire. Stock compression on a 7900 is 170-180. I must say don't like the looks of that piston ring. The throttle response should be quick, maybe not as quick as a 361, but close.



Thanks Andy. I found it in the IPL as well. I took the boot off of the ignition during disassembly and fogot that went on there. At least that was my only spare part. Compression on the 64cc P&C I removed was 175 PSI. Throttle response is fine, just not as snappy as my 361.


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## blsnelling (Dec 3, 2008)

scotclayshooter said:


> davefr said:
> 
> 
> > Your wish is my command. This is how I did mine. (I knew Husquvarna parts were good for something!!):
> > http://www.arboristsite.com/showthread.php?t=75018&highlight=dolmar+dual+port+muffler



Thanks guys. I did use the search funtion and did not find that. That's what I thought was in there. I really don't see any point in taking it apart to increase the flow through the baffler. That's a lot of area the way it is. I think I'll just add a Husky deflector to the other side and be done with it.


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## blsnelling (Dec 3, 2008)

brages said:


> Is a scratch like that in the cylinder no big deal? I cleaned up my MS290 cylinder and have about six or seven scratches that look like that.


I don't think anything's hurt. I'm now wondering if it came from me driving in the impulse nipple after the P&C was on. There may have been a couple chips of brass get in there. I don't know. I think it'll be fine though.


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## davefr (Dec 3, 2008)

blsnelling said:


> Thanks guys. I did use the search funtion and did not find that. That's what I thought was in there. I really don't see any point in taking it apart to increase the flow through the baffler. That's a lot of area the way it is. I think I'll just add a Husky deflector to the other side and be done with it.



P.S. I would add a couple more air intake slits to the shroud to feed that 85 cc BB kit. It seems that's a weakness in the Dolmar design. There's also a later model shroud with a better pre-screen design. (any color you want as long as it's black)


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## blsnelling (Dec 3, 2008)

I saw the new filter cover else where. I wonder what a new filter and engine cover would cost?


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## davefr (Dec 3, 2008)

blsnelling said:


> I saw the new filter cover else where. I wonder what a new filter and engine cover would cost?



<$10. P/N 038118221


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## blsnelling (Dec 3, 2008)

davefr said:


> <$10. P/N 038118221



Is that black or grey? Filter cover or engine cover? Can I buy Dolmar/Makita parts online? I know, these are newbie questions. These are my first Dolmar parts to buy though.

Here's my shopping list.

Husky deflector and screen
Chain catcher
Clutch springs
Clutch drum retaining washer
Oil hose
Fuel and oil caps
Top AV spring
Filter cover and engine cover


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## epicklein22 (Dec 3, 2008)

Just put the thing in wood already.


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## davefr (Dec 3, 2008)

blsnelling said:


> Is that black or grey? Filter cover or engine cover? Can I buy Dolmar/Makita parts online? I know, these are newbie questions. These are my first Dolmar parts to buy though.
> 
> Here's my shopping list.
> 
> ...



The part number I gave you is the new style cover (black). I don't know if there's a Makita gray version. Yes, Dolmar/Makita parts are easy to buy online. It's actually easier to get Dolmar parts then most Stihl parts. Just choose a site sponsor and enter the P/N - I used Edge and Engine and they were very fast to ship even for not so common parts.

You can download the entire parts list from Makita.com. (unlike Stihl's primitive website)


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## blsnelling (Dec 3, 2008)

davefr said:


> The part number I gave you is the new style cover (black). I don't know if there's a Makita gray version. Yes, Dolmar/Makita parts are easy to buy online. It's actually easier to get Dolmar parts then most Stihl parts. Just choose a site sponsor and enter the P/N - I used Edge and Engine and they were very fast to ship even for not so common parts.
> 
> You can download the entire parts list from Makita.com. (unlike Stihl's primitive website)



I found Edge & Engines parts. However, the filter cover and engine cover PNs from the IPL don't come up. I can't find the matching engine cover either. Do you have the grey PNs?

edit: The black engine cover PN is 038118291. *Does anyone know the PNs for the style covers in grey?*


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## cuttinscott (Dec 3, 2008)

davefr said:


> Yes, but who's the actual manufacturer? Is it from a major manufacturer or some no name sweat shop in China?



China Crapola :bang: :bang: Why dump china non quality Piston and cylinder onto a Quality piece of equipment that many of you make a living with????? When the piston crumbles and takes out the bottom end you will regret this.



JMO

Scott


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## Lakeside53 (Dec 3, 2008)

Yep... Even Baileys for a long time said "not recommended for professional use" or something like that. I don't have any problem in getting the "real pros" to put OEM parts on their saws... but pro's rarely cook cylinders anyhow - they are "in-tune" with their saw, use fresh gas etc. The rest of the saws look like crap though


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## Former Saw Builder (Dec 3, 2008)

blsnelling said:


> Is that black or grey? Filter cover or engine cover? Can I buy Dolmar/Makita parts online? I know, these are newbie questions. These are my first Dolmar parts to buy though.
> 
> Here's my shopping list.
> 
> ...



Brad I have a lot of these parts I sent you my phone number...


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## Jacob J. (Dec 3, 2008)

cuttinscott said:


> China Crapola :bang: :bang: Why dump china non quality Piston and cylinder onto a Quality piece of equipment that many of you make a living with????? When the piston crumbles and takes out the bottom end you will regret this.
> 
> 
> 
> ...



I ran one of the first generation big bore kits (modified) on my 460 on a straight-falling job near Oakland, Oregon for about 6 months (July '06-Jan '07) and it held up just fine. That saw cut a million and three-quarters board feet. I traded it to a logging company who is now using it on their landings and it's still going. 

A straight falling scenario means you're stumping all day long. No limbing, no bucking- there's a processor that does that. That saw cut about 240 trees/day on average- 11" to 36" DBH.

My first choice isn't necessarily aftermarket parts on my pro saws but in a crunch, they can do the job. Like Andy said, it's how 'in-tune' with your saw you are and how well you maintain it.


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## Andyshine77 (Dec 3, 2008)

Brad's just testing the kits out for Bailey's, no need for all the darn negativity.


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## Metals406 (Dec 3, 2008)

Andyshine77 said:


> Brad's just testing the kits out for Bailey's, no need for all the darn negativity.


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## 4492011 (Dec 3, 2008)

blsnelling said:


> I found Edge & Engines parts. However, the filter cover and engine cover PNs from the IPL don't come up. I can't find the matching engine cover either. Do you have the grey PNs?
> 
> edit: The black engine cover PN is 038118291. *Does anyone know the PNs for the style covers in grey?*



You need to contact a makita dealer or order them from makita online they are the only ones with the grey covers. The one that I ordered did come as new style air inlet much larger and screened.


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## Haywire Haywood (Dec 3, 2008)

Andyshine77 said:


> Brad's just testing the kits out for Bailey's, no need for all the darn negativity.



+100 I'm outta bullets or I'd give you a couple more dots.



Jacob J. said:


> I ran one of the first generation big bore kits (modified) on my 460 on a straight-falling job near Oakland, Oregon for about 6 months (July '06-Jan '07) and it held up just fine. That saw cut a million and three-quarters board feet. I traded it to a logging company who is now using it on their landings and it's still going.
> 
> A straight falling scenario means you're stumping all day long. No limbing, no bucking- there's a processor that does that. That saw cut about 240 trees/day on average- 11" to 36" DBH.
> 
> My first choice isn't necessarily aftermarket parts on my pro saws but in a crunch, they can do the job. Like Andy said, it's how 'in-tune' with your saw you are and how well you maintain it.



Thank you. 

Everyone realizes by now that they are aftermarket and don't live up to mahle quality, they aren't pretending to... time to stop :deadhorse: and let the man test them.
Ian


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## IchWarriorMkII (Dec 3, 2008)

Cool, I hope it runs good.


How does it run in the high altitudes? Or, can you test that when you get it bolted down?

I'd go for a light weigh, high power 85cc saw like that.


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## Sethro (Dec 3, 2008)

Thanks Brad and Nick ! Looks good very interesting stuff !


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## Lakeside53 (Dec 3, 2008)

Andyshine77 said:


> Brad's just testing the kits out for Bailey's, no need for all the darn negativity.



Let's just call it a balance... keeps the exuberant sunshine in check..


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## drmiller100 (Dec 4, 2008)

on the muffler, take a 6 inch long 3/8 ratchet extenstion. put the small end down in the center, and beat with a hammer.

you are taking that shroud bent over at a 90, and opening it up.

There is no difference in performance from doing that compared to tearing apart the entire muffler, cutting the lip as shown, and reassembling.

my 7900's are both lazy. they are not snappy, but they do run better then some others. they also like heat in the pipe, but that could be because i run them a little fat.

I really wish there was a lot more meat on top of the exhaust port. I can't get enough exhaust duration on the stock 7900.

like the other guy said, the ishroud around the intake is a known restriction.


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## drmiller100 (Dec 4, 2008)

also, snelling, send me your address, and i'd love to ship you a saw for your GTG to see how much slower mine is......


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## blsnelling (Dec 4, 2008)

drmiller100 said:


> also, snelling, send me your address, and i'd love to ship you a saw for your GTG to see how much slower mine is......



Sounds like fun. I'm assuming yours is ported. I'm sure there would be a stock 7900 there. We coul run an assorment of 7900s and see how they compare.


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## blsnelling (Dec 7, 2008)

Here's the 7900 BB in some good sized wood. It's running great. I set it with a tach to 13,500 since I can't tune it by ear because of the limited ignition. When I got it home I pulled a compression check of 160 PSI.

<object width="425" height="344"><param name="movie" value="http://www.youtube.com/v/5qLy9TmoAYc&hl=en&fs=1"></param><param name="allowFullScreen" value="true"></param><param name="allowscriptaccess" value="always"></param><embed src="http://www.youtube.com/v/5qLy9TmoAYc&hl=en&fs=1" type="application/x-shockwave-flash" allowscriptaccess="always" allowfullscreen="true" width="425" height="344"></embed></object>


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## mattmc2003 (Dec 7, 2008)

so does it feel more powerful than a 7900?


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## 7oaks (Dec 7, 2008)

Impressive cutting speed and no apparent bogging...Not a real "throaty" sound though. I want one  ...Carl


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## JT78 (Dec 7, 2008)

Id like to see a side by side comparison because I run a 28 on my stock 7900 and it cuts about the same speed as yours and I am assuming you were running a 20 or 24 on that one.


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## mattmc2003 (Dec 7, 2008)

sometimes they feel fast in your hands and look slower when viewed on camera. Looks can be decieving. I wanna see a side by side. That will determine which kit i buy...


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## blsnelling (Dec 7, 2008)

I don't have a stock 7900 and have used one for only a couple cookies at a GTG. Not enough for me to compare. BTW, the muffler is stock on this one still. No muffler mod yet.


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## ericjeeper (Dec 7, 2008)

*Looks like we need*

A time trial on the beech log sometime soon Brad.. That will show us the results.


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## blsnelling (Dec 7, 2008)

ericjeeper said:


> A time trial on the beech log sometime soon Brad.. That will show us the results.



It sure would.


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## Former Saw Builder (Dec 7, 2008)

blsnelling said:


> Here's the 7900 BB in some good sized wood. It's running great. I set it with a tach to 13,500 since I can't tune it by ear because of the limited ignition. When I got it home I pulled a compression check of 160 PSI.
> 
> <object width="425" height="344"><param name="movie" value="http://www.youtube.com/v/5qLy9TmoAYc&hl=en&fs=1"></param><param name="allowFullScreen" value="true"></param><param name="allowscriptaccess" value="always"></param><embed src="http://www.youtube.com/v/5qLy9TmoAYc&hl=en&fs=1" type="application/x-shockwave-flash" allowscriptaccess="always" allowfullscreen="true" width="425" height="344"></embed></object>



Brad, nice video - you should have those parts I sent out Monday or Tuesday, You don't owe me anything - Merry Christmas, Eric


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## blsnelling (Dec 7, 2008)

EdRitchey said:


> Brad, nice video - you should have those parts I sent out Monday or Tuesday, You don't owe me anything - Merry Christmas, Eric



Thank you Santa Claus!!!


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## mattmc2003 (Dec 7, 2008)

What kind of wood is that?


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## blsnelling (Dec 7, 2008)

The first log is Hackberry and was solid. I'm not sure if the second one is or not. It was solid towards the left end.


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## CHEVYTOWN13 (Dec 7, 2008)

*Almost sounds like it has a muffler mod!*

Someone buy this man a cerveza!


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## blsnelling (Dec 7, 2008)

It'll probably get one this week. Did I ever mention that...."*Stock Sucks!*"


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## blsnelling (Dec 8, 2008)

I'm going to use a Husky deflector and add another port on the other side of the muffler. I will not be removing the inner baffle. It's plenty open the was it is for a work saw.


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## davefr (Dec 8, 2008)

blsnelling said:


> Here's the 7900 BB in some good sized wood. It's running great. I set it with a tach to 13,500 since I can't tune it by ear because of the limited ignition. When I got it home I pulled a compression check of 160 PSI.



Setting it at 13,500 via a tach won't guarantee it's not lean. You could be lean but with the rev limiter kicking in.

Apparently the way to set these 7900's is by starting out overly rich and <<13,500. Start adjusting it leaner until it just starts to hit 13,500. Beyond that the tach will go nuts once the limiter is starting to do it's thing. After that try timed cuts.

The service manual is totally worthless when it comes adjusting H. All they say is to use a tach. but they don't say how.

Rev. limiting saws are a PIA to adjust.


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## blsnelling (Dec 8, 2008)

davefr said:


> Start adjusting it leaner until it just starts to hit 13,500. Beyond that the tach will go nuts once the limiter is starting to do it's thing.



That's what I did so as to not mistake it for the limiter. I'm really considering the 272 coil mod. I *HATE *limited ignitions!!!!!!!!!!!!!!


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## scotclayshooter (Dec 8, 2008)

davefr said:


> Setting is at 13,500 via a tach won't guarantee it's not lean. You could be lean but with the rev limiter kicking in.
> 
> Apparently the way to set these 7900's is by starting out overly rich and <<13,500. Start adjusting it leaner until it just starts to hit 13,500. Beyond that the tach will go nuts once the limiter is starting to do it's thing. After that try timed cuts.
> 
> ...



My one hits 14,200 before going crazy.


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## blsnelling (Dec 8, 2008)

Where there different coils on these? Mine is red. I think I've seen others that were black.


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## THALL10326 (Dec 8, 2008)

blsnelling said:


> It'll probably get one this week. Did I ever mention that...."*Stock Sucks!*"



LOL, whatcha mean Stock Sucks, hows dares ya say such a thing. The EPA is on their way to your house with dynometers and carbon emmision meters, ya better high tail it to the hills Brad,:hmm3grin2orange: :hmm3grin2orange:


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## blsnelling (Dec 8, 2008)

THALL10326 said:


> LOL, whatcha mean Stock Sucks, hows dares ya say such a thing. The EPA is on their way to your house with dynometers and carbon emmision meters, ya better high tail it to the hills Brad,:hmm3grin2orange: :hmm3grin2orange:



My truck is loaded and I"M OUTA HERE!!!!!!!!!!!!!!!!!!!! Thanks for the warning Thall. Now where did you say to hide these things? What was your address again?


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## THALL10326 (Dec 8, 2008)

blsnelling said:


> My truck is loaded and I"M OUTA HERE!!!!!!!!!!!!!!!!!!!! Thanks for the warning Thall. Now where did you say to hide these things? What was your address again?



Just come to the fork in the road and go striaght ahead, I'll meet ya down in the woods, I got the hole already dug. Hurry, I just seen them cats going by my house heading your way,LOLOLOLOL


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## blsnelling (Dec 8, 2008)

I left only the 361 since I'm sure it'll pass any tests they've got.


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## Lakeside53 (Dec 8, 2008)

blsnelling said:


> I left only the 361 since I'm sure it'll pass any tests they've got.



MS361 - "Snellerized":monkey:


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## blsnelling (Dec 8, 2008)

Lakeside53 said:


> MS361 - "Snellerized":monkey:



That means it's better than a 361!!:greenchainsaw:. It's a BS361, LOL.


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## Peacock (Dec 8, 2008)

blsnelling said:


> I left only the 361 since I'm sure it'll pass any tests they've got.



You need a couple 4-mix trimmers and a 441 to buy you some EPA credits for the toys!


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## Wortown Mick (Dec 9, 2008)

Hey brad, do the transfers line up any better with the lower end? 

On the stock mahle theres a ton of material to be removed to blueprint the transfers to the cases.


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## blsnelling (Dec 9, 2008)

Wortown Mick said:


> Hey brad, do the transfers line up any better with the lower end?
> 
> On the stock mahle theres a ton of material to be removed to blueprint the transfers to the cases.



I honestly have no idea since I had no plans of porting it before installation. Sorry.


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## brncreeper (Dec 9, 2008)

I wish Bailey's would look into pop up pistons, kinda like you custom 084. Compression=hp.


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## blsnelling (Dec 9, 2008)

brncreeper said:


> I wish Bailey's would look into pop up pistons, kinda like you custom 084. Compression=hp.



That's a whole different ball game. That piston was cut to exact tolerances as measured on my saw. I think that would be too risky to do on a retail level. Every saw is a little different.


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## 4mocajuns (Dec 9, 2008)

So any idea on a date or price?


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## blsnelling (Dec 9, 2008)

I don't know. Gregg mentioned something about a couple months after the prototypes are tested.


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## blsnelling (Dec 17, 2008)

Here's the 7900BB in the same small wood I've been testing in. It's about 10" Poplar. The wood is frozen and the chain has high rakers on a round ground chain. The saw is wearing a 8-pin rim. I was testing another saw and just grabbed it with the chain it had on it. I made a few cuts. I started with it tuned where I had it last time at 13,500. I then went a 1/4 leaner and it didn't change much. I went another 1/8 turn leaner and still no change. So I went back where I started and 1/4 richer. Voila. This saw likes to run rich. I didn't have enough time for any more testing so this is it for now. I didn't even check the RPMs after the last adjustment. Even with a much lesser chain, it's faster than a 361 I just ported running a 7-pin. And it should be with that many cc advantage and a larger rim.

2.85 seconds

<object width="425" height="344"><param name="movie" value="http://www.youtube.com/v/9hiajey9ic8&hl=en&fs=1"></param><param name="allowFullScreen" value="true"></param><param name="allowscriptaccess" value="always"></param><embed src="http://www.youtube.com/v/9hiajey9ic8&hl=en&fs=1" type="application/x-shockwave-flash" allowscriptaccess="always" allowfullscreen="true" width="425" height="344"></embed></object>



Here's the 361 for comparison.

<object width="425" height="344"><param name="movie" value="http://www.youtube.com/v/Qhxg8bkQtvs&hl=en&fs=1"></param><param name="allowFullScreen" value="true"></param><param name="allowscriptaccess" value="always"></param><embed src="http://www.youtube.com/v/Qhxg8bkQtvs&hl=en&fs=1" type="application/x-shockwave-flash" allowscriptaccess="always" allowfullscreen="true" width="425" height="344"></embed></object>


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## Metals406 (Dec 17, 2008)

They both sound good Brad.


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## Andyshine77 (Dec 17, 2008)

Brad, both saws are running really well. My ported 7900 likes to run leaner than the stock 7900's, if It's running rich at all it really bogs down.


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## blsnelling (Dec 17, 2008)

Hi Ian!


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## Haywire Haywood (Dec 17, 2008)

Yup.


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## Lakeside53 (Dec 17, 2008)

Brad.... get some real wood. 10 inch is tiny for big saws.... Bury it in some 24-36 inch for a real test...


If I put my 066 into 10 inch poplar, I doubt I could bog it at all.


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## VI sawguy (Dec 17, 2008)

Here is the Tech. bulletin on the new filter system for the 7900

http://arboristsite.com/attachment.php?attachmentid=84283&stc=1&d=1229567846


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## Lakeside53 (Dec 17, 2008)

Accessory...:monkey: Should be stock... It's an $80 Filter tax!:greenchainsaw:


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## blsnelling (Dec 17, 2008)

Lakeside53 said:


> Brad.... get some real wood. 10 inch is tiny for big saws.... Bury it in some 24-36 inch for a real test...
> 
> 
> If I put my 066 into 10 inch poplar, I doubt I could bog it at all.


I would if I had some I know! What's a guy doing with 20 chainsaws and no wood?:bang:


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## blsnelling (Dec 17, 2008)

Lakeside53 said:


> Accessory...:monkey: Should be stock... It's an $80 Filter tax!:greenchainsaw:



OUCH!!!!!!!!!


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## 04ultra (Dec 17, 2008)

blsnelling said:


> I would if I had some I know! What's a guy doing with 20 chainsaws and *no wood*?:bang:






*Sounds like you need Viagra.........*


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## Lakeside53 (Dec 17, 2008)

Hey guys... one of you local tree services give Brad a nice section from a 24 inch log... heck, he'll even port a saw in exchange.


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## Tzed250 (Dec 17, 2008)

04ultra said:


> *Sounds like you need Viagra.........*



Thats gonna leave a mark...


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## blsnelling (Dec 17, 2008)

Lakeside53 said:


> Hey guys... one of you local tree services give Brad a nice section from a 24 inch log... heck, he'll even port a saw in exchange.


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## Lakeside53 (Dec 17, 2008)

mark? I've been told it colors the vision.. Blue... Makes the Makita's look very bright, and the stihl's dull.


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## wkpoor (Dec 17, 2008)

Brad, just bring it over on the 3rd. I've got a bunch of 24-48" stuff around.


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## blsnelling (Dec 18, 2008)

wkpoor said:


> Brad, just bring it over on the 3rd. I've got a bunch of 24-48" stuff around.



It's looking like I may be able to do that. I'm sure you've got plenty of wood to give my saws a good workout.


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## Haywire Haywood (Dec 18, 2008)

Lakeside53 said:


> Accessory...:monkey: Should be stock... It's an $80 Filter tax!:greenchainsaw:



I agree, but even with the filter tax, it's how much cheaper than the MS 460 that it whips the snot out of? :hmm3grin2orange: 

Just my subtle contribution to the brand war,
Ian


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## Lakeside53 (Dec 18, 2008)

it's not.. you need to read the "other" thread...


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## blsnelling (Dec 18, 2008)

I don't know about price and am a Stihl guy, but a 7900 with nothing more than a muffler mod has significantly more power than a 460 with dual port muffler cover. The one I ran belongs to EricJeeper. Very impressive saw.


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## blsnelling (Dec 27, 2008)

Today was the first time anyone else got to run this 7900BB. My BIL were out for a little saw testing today. We started with the 064 I just rebuilt. We were both really impressed with it. Very strong saw. Then I got out the Makita. He was even more impressed with it. The 064 did have a 24" bar where as the 7900BB only had a 20" bar. But still, he was impressed with the power, speed, and smoothness in the cut. Just thought I'd pass along the first outside opinion.


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## husky455rancher (Dec 27, 2008)

do they know what their gonna charge for the kit?


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## blsnelling (Dec 27, 2008)

husky455rancher said:


> do they know what their gonna charge for the kit?



I have no idea. You'll have to ask Baileys.


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## Wet1 (Dec 27, 2008)

I would expect it to be in line with their other BB kits.


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## AKDriveSprocket (Dec 27, 2008)

I think it is up on there web page at 125.00.


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## M.R. (Dec 27, 2008)

When you get some time on this PS 7900 big bore guy, would you be to kind enough to compare it a little bit to a 064? 

Thanks 

Stihl026
DCS540
064 
153

NIB DCS6401 .......


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## J.Gordon (Dec 28, 2008)

AKDriveSprocket said:


> I think it is up on there web page at 125.00.



Could you post a link please? I couldn't find it and would like to see what a ported BB7900 would do against my EHP7900. More power at the same weight is always good for me.


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## M.R. (Dec 28, 2008)

http://www.baileysonline.com/itemdetail.asp?item=BBN+7900&catID=


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## J.Gordon (Dec 28, 2008)

Thanks for the link! have a little rep.


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## blsnelling (Dec 28, 2008)

It shows as out of stock already. Did they have inventory that already sold out, or is this basicaly just a preorder type thing?


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## Cedarkerf (Dec 28, 2008)

blsnelling said:


> Today was the first time anyone else got to run this 7900BB. My BIL were out for a little saw testing today. We started with the 064 I just rebuilt. We were both really impressed with it. Very strong saw. Then I got out the Makita. He was even more impressed with it. The 064 did have a 24" bar where as the 7900BB only had a 20" bar. But still, he was impressed with the power, speed, and smoothness in the cut. Just thought I'd pass along the first outside opinion.


How big was the wood you were cutting?


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## blsnelling (Dec 28, 2008)

Cedarkerf said:


> How big was the wood you were cutting?



The bars were buried. I'm trying to get a good sized test log at home where I can video timed cuts.


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## J.Gordon (Dec 28, 2008)

*85cc for $680.00 not bad*

Pretty cheap if it is a reliable mod. You can have a light 85cc saw for $680.00 – shipping if you get it from Bailey"s. Now that’s bang for the buck! 

Thanks for your efforts and time blsnelling!


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## CHEVYTOWN13 (Dec 28, 2008)

*BB Homes!*

I can already see it hometowns...this kit is going to make THE BIG TIME DOLMAR GANG even bigger!


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## 4mocajuns (Dec 28, 2008)

*Availability*

OK Bailey's count me in....... when are they gonna be available?
Oh and when I get one who wants to port it for me?


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## mattmc2003 (Dec 28, 2008)

So will it be completely bolt on kit? or will it have to be customized somewhat to fit a 6401? If it is bolt on, count me in too. So how long before it is listed for sale?


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## Cedarkerf (Dec 28, 2008)

Havent fallowed close maybe you already answerd on the big bore kits where do you set RPM stock or?


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## Grande Dog (Dec 29, 2008)

4mocajuns said:


> OK Bailey's count me in....... when are they gonna be available?
> Oh and when I get one who wants to port it for me?


Howdy,
At this time we can only take back orders for future shipment. If you look at the thread from the beginning , you'll see Brad had to narrow the skirts on the pistons. So far, I think this is the only issue with bringing them to market. It will take 6-8 weeks to have them on the shelf once we give the OK. Once again this is considering that the piston is the only change. I also have a 2mm thick gasket in the works, so this kit will also fit the Solo 665, 675, and 681.
Gregg


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## Lakeside53 (Dec 29, 2008)

2mm? Would that be in the form of a metal spacer/gasket?


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## Grande Dog (Dec 29, 2008)

Howdy,
We're working with a 1mm thick steel with .5mm gasket material on both sides.
Gregg


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## 4mocajuns (Dec 29, 2008)

SO what is the displacement on the solo gonna be? 87 cc?


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## Grande Dog (Dec 29, 2008)

Yes, it should be close to 87.


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## J.Gordon (Dec 29, 2008)

Grande Dog said:


> Howdy,
> At this time we can only take back orders for future shipment. If you look at the thread from the beginning , you'll see Brad had to narrow the skirts on the pistons. So far, I think this is the only issue with bringing them to market. It will take 6-8 weeks to have them on the shelf once we give the OK. Once again this is considering that the piston is the only change. I also have a 2mm thick gasket in the works, so this kit will also fit the Solo 665, 675, and 681.
> Gregg




Hey Gregg, there isn’t any chance I could talk you into a big bore kit for the 5100 Dolmar is there?
If you do, count me in on that one also!


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## 4mocajuns (Dec 29, 2008)

Do you guys ever go through the trouble of dynoing your BBK's? Just curious what these saws would be comperable to powerwise.


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## Fl_Airboater (Jan 7, 2009)

Any more news or testing results with this kit. I really want to get one for my 6401.


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## blsnelling (Jan 7, 2009)

I ran it with the same bar and chain as a Solo 681 at the GTG. The BB outcut it by a small margin. However, the 681 had a 7-pin and the BB had a 8-pin. We also did some timed cuts with work chains in some firewood and the BB was beating a 7900 as well. I've got the saw for sale in the Tradin Post.


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## Lakeside53 (Jan 7, 2009)

Did you have base gasket in the BB?


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## M.R. (Jan 7, 2009)

Fl_Airboater said:


> Any more news or testing results with this kit. I really want to get one for my 6401.



+1 

Was sort of hoping the hear some of the thougths/comments from a few of the guys at the GTG if they had a chance to run it? But might be sounding like a broken record. :deadhorse: 

The time shown in the small 10" x10" beam dosen't- really seem to show how this saw should run.

Any chance of this saw or one like it, being at the GTG in the PNW?


NIB DCS6401 waiting on the PC 7900 or BB? & air filter VS


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## Fl_Airboater (Jan 7, 2009)

blsnelling said:


> I ran it with the same bar and chain as a Solo 681 at the GTG. The BB outcut it by a small margin. However, the 681 had a 7-pin and the BB had a 8-pin.



How do you think the the BB would have done against the 681 if it would have had a 7 pin also? Thanks


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## blsnelling (Jan 7, 2009)

M.R. said:


> The time shown in the small 10" x10" beam dosen't- really seem to show how this saw should run.


That's because the other saws were wearing fast chains and mine had a regular round ground Stihl RSC on it. We did not record the times when I ran a faster chain on it. That was all done after the racing was done.



Fl_Airboater said:


> How do you think the the BB would have done against the 681 if it would have had a 7 pin also? Thanks


I have no idea. The only way to know would be to try it.



Lakeside53 said:


> Did you have base gasket in the BB?


It was built just as desribed in the review thread. No base gasket.


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## wkpoor (Jan 7, 2009)

I think Brad described it perfect. If both the 681 and 6400BB wore the same B/C and 7/8pin they would be neck in neck. That Dolmar BBK would be a good deal.


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## woodchuck361 (Jan 7, 2009)

I ran both the BB and my stock 7900. I liked the BB and will get one. I could feel a difference in the amount of torque the BB made. I have always felt the 7900 is a great saw but you can't lean on them with a big bar the BB made a difference and I felt I could lean on it more. 

The 681 solo was impressive. Very strong.


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## Andyshine77 (Jan 8, 2009)

The BB ran really well, but I look at like this. The BB is a good, cheep upgrade to a Home Depot 6400 or an old worn out 7900, but I wouldn't consider it a real upgrade over a good running OEM 7900.

 Andy.


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## blsnelling (Jan 8, 2009)

Andyshine77 said:


> The BB ran really well, but I look at like this. The BB is a good, cheep upgrade to a Home Depot 6400 or an old worn out 7900, but I wouldn't consider it a real upgrade over a good running OEM 7900.
> 
> Andy.



Makes sense to me. That's a very fair assessment.


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## Andyshine77 (Jan 8, 2009)

For the price you can't get anything close to it. I'm sure it will make a hell of a firewood saw for somewone.


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## blsnelling (Jan 8, 2009)

The 7900BB has been spoken for and will be shipping out tomorrow.


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## Andyshine77 (Jan 8, 2009)

I didn't think it would take to long.


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## epicklein22 (Jan 8, 2009)

Options are always nice. Being around 120 for a BB kit makes it close to the 190 that buys a OEM 7900 top end. I think either way you go, the Dolmar is a nice saw for the money. I will have one some day. 

Brad, how did it compare to the 064?


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## blsnelling (Jan 8, 2009)

epicklein22 said:


> Brad, how did it compare to the 064?



7900BB 6.97
064 7.00

Both were wearing round ground Stihl RSC. The 064 is still bone stock except for the muffler mod. The 7900BB is muff modded as well. Interesting results. I believe they're both 85cc. I'm very impressed with the 064 for a stock saw. I should have the 066 P&C in a few days. It's on its way.


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## specialistj (Mar 3, 2009)

Called Bailey's and they plan to have 500 of the kits in on the 14th of April.


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## Fl_Airboater (Mar 3, 2009)

I ordered mine a few days ago, Looks like I'll be getting one of these in the first batch. Can't wait to put mine on my 6401. I just use it for (mainly)hurricane cleanup around mine and my neighbors houses but the added torque will be nice when I tangle with one of these big oaks when they go down in a storm.


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## M.R. (Mar 3, 2009)

specialistj said:


> Called Bailey's and they plan to have 500 of the kits in on the 14th of April.



Any word or update on the VS Filters?


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## Fl_Airboater (Mar 3, 2009)

They emailed me this on Feb 25 2009:

_*Currently our vendor is giving us a date of : 03/16/09

The price is currently going to be : $129.95

You may place an order and we can get you in line for one of these and
we won't charge your credit card until it ships , but it will prevent
you from waiting till the second batch. Just give us a call @ 1-800-322-4539
and any agent can help you.*_


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## 2000ssm6 (Mar 3, 2009)

Fl_Airboater said:


> They emailed me this on Feb 25 2009:
> 
> _*Currently our vendor is giving us a date of : 03/16/09
> 
> ...



Fred was asking about the new updated air filters.


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## Fl_Airboater (Mar 3, 2009)

2000ssm6 said:


> Fred was asking about the new updated air filters.



10-4.............I am interested in the filters also so that's good news as well.


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## Lugnutz (Mar 3, 2009)

just got my 6401, needs the bb kit new air filter and one of them fancy new designed black filter housings ( seems mine is the old style ) Any one have pics of the new style so I can compare??


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## Andyshine77 (Mar 3, 2009)

Lugnutz said:


> just got my 6401, needs the bb kit new air filter and one of them fancy new designed black filter housings ( seems mine is the old style ) Any one have pics of the new style so I can compare??




Here you go.http://www.arboristsite.com/showthread.php?t=51623&highlight=hood&page=2


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## Lugnutz (Mar 4, 2009)

Thanks!! Yup mine is old style...gonna have to find me a new one.


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## Edge & Engine (Mar 4, 2009)

New air filter cover with mesh prefiltering:
http://www.edgeandengine.com/store/index.php?main_page=product_info&cPath=93_180&products_id=39826


But, if you're planning on upgrading to the Heavy duty filter kit that Dolmar is coming out with, you'll be tossing the old filter cover anyways. (The filter kit has a new cover to accommodate the larger filter).


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## Lugnutz (Mar 4, 2009)

Cool! Didn't know it was going to come with its own cover, but the real question is...... is it gonna flow more air and filter better?


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