Makita 6401 to 7901 Plus porting the 7900 and the Solo 681

[fordf150]

Adding to what @166 said. I have a tree trimming outfit running a stock 7910 with a 36" bar as their stumping setup. Not a thing wrong with how a 7910 runs straight from the box. I actually like the exhaust note they have with the SLR intact

 

[166]

7900 is limited at 13500 and 7910 is 12800. Last I checked the part number for the 7900 coil updates to a coil/flywheel combo.
The 13500 coil works fine for stock saws...mine likes to be tuned at 13200 but that is a bone stock saw. Ported I would imagine needing a few more rpm and if running the 12800 coil in smaller wood the saw would be against the limiter.

There is an update kit for the '01-'03 6400-7900 black coil saws to the red coil and newer flywheel.

The Red 13,500 coil from 2004 - current PS-6400's is still a good part number (038 143 041).

 

[fordf150]

There is an update kit for the '01-'03 6400-7900 black coil saws to the red coil and newer flywheel.

The Red 13,500 coil from 2004 - current PS-6400's is still a good part number (038 143 041).

Ok. I need to do some more reading and memorization.

 

[Locust Cutter]

Adding to what @166 said. I have a tree trimming outfit running a stock 7910 with a 36" bar as their stumping setup. Not a thing wrong with how a 7910 runs straight from the box. I actually like the exhaust note they have with the SLR intact

That's a hell of a lot of bar for that oiler...

 

[Poleman]

See why I'm so confused.....to me a red coil is 12,8.....kinda like who's on first......

Sent from my SAMSUNG-SM-G900A using Tapatalk

 

[redfin]

That's a hell of a lot of bar for that oiler...

Are these cheap on the oil?

 

[fordf150]

Yep. 28" is all they will oil good. 32" it's acceptable. They are running the 36" and so far can't say it is looking to bad. I posted a picture of it somewhere.

 

[166]

Original black coil for the PS-6400-7300-7900 from 2001 - mid 2004 production.
13,500 RPM Rev Limiter


Optimized coil used on PS-7300 & PS-7900 from mid 2004 to the release of the PS-7310 & PS-7910
This coil is still used on the PS-6400 today.
13,500 RPM Rev Limiter

The PS-7310 & PS-7910 use the same flywheel as the later model 7900's but use a black coil governed to 12,800 RPM.

There was never a 12,500 coil for these saws. But if you find a Blue coil on one that is the unlimited coil. There is one of these floating around somewhere and last I knew it was in Virginia.

 

[noshow74]

Why yes, yes you will.

This was today in Red Oak with the saw tuned at 14.4k.

So what all has been done to it? Damn thing is fast lol! I recently picked up a used 441cm and haven't even cut with it yet...it might be for sale after seeing this.

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[benp]

So what all has been done to it? Damn thing is fast lol! I recently picked up a used 441cm and haven't even cut with it yet...it might be for sale after seeing this.

Sent from my SAMSUNG-SM-G870A using Tapatalk

Ported and unlimited coil.

 

[drf255]

Ported and unlimited coil.

Your saw is bad ass

 

[MillerModSaws]

Happy Monday morning Randy!

 

[nnero]

Good thread as usual Mastermind!! All this Dolmar stuff going is great. Dont do what i did. Ordered a nice new red coil/flywheel set from fordf150 for my 7900 and then proceeded to not fully tighten the flywheel nut and sheered the key off lol. Lined it back up and tightened and its fine but it still irritates me. Got the 7900 out and cleaned off this weekend, just have to pull the oiler for rebuild and should be good to go for the winter. Im getting excited...

 

[blsnelling]

Sounds like you could just put your old flywheel back on.

 

[nnero]

The saw came without a coil and the original flywheel went with the old, black coil. that one was sheared anyways haha.

 

[bryanr2]

ya know, this thread would have been easier to find if the title started with "Mastermind meets"

 

[Mastermind]

I've already done a Mastermind Meets on the 7900.

 

[bryanr2]

I've already done a Mastermind Meets on the 7900.

I know.

 

[Mastermind]

OK.......the finished Solo jug.

 

[blsnelling]

Looks great Randy. Do you widen the intake side transfers on these?