Why so few reed valves these days?

[RaisedByWolves]

I was thinking sap, but pest is way to smart for that, but...

No not sappish, I think this one has value, just needs to be teased to the surface.opcorn:

 

[sawinredneck]

No not sappish, I think this one has value, just needs to be teased to the surface.opcorn:

Just gonna have to knock him around a bit like you did me:deadhorse:

 

[Lakeside53]

Just make sure you knock around the other ANDY!!!!!:angry2:

 

[blis]

.....

Most everything you can find pertains to bikes and as I understand it not much of it works for our saws.



I can understand how a piston port could run higher rpm's than a given reed motor and how a reed motor with stiffer petals could achieve the same HP/RPM's but at a loss of low end torque.



What I would like to find out is fi there is anyone out there that has good "Woods" numbers for a reed engine saw jiven the stock reed stiffness.:help:

got no numbers, but reed valve type (crankcase flush) is alot more efficient than normal piston type engine and the rpm´s wont be a issue (reedvalve type can easily rev +13.5k rpm while still having good low end torque)... As a plus side on reed valve engine you can always switch reeds to get rise/lower the rpm of max power....

Anyway, the biggest issue with reed valve engines not used in chainsaws is that it costs alot money to redesing a engine and since piston type engines still pass the epa regulations there is no need for manufacturers to switch into reed valve engines...

 

[PES+]

OK I will no longer question what others believe

And I can be too much of a smart alec sometimes

So I wll just read threads for a while and keep my mouth shut

Maybe I'll learn something finally agter 30 years of working on these darn things

:angel: opcorn:

 

[PES+]

I started the thread to make people think and that makes me a jackass

I know nothing it's OK

I now know better

 

[PES+]

PEST stands for
Power Equipment Service and Technology

I shall re-register to avoid further confusion

 

[computeruser]

Chill out already. No need to run away, change logins, whatever. You raised a perfectly good question.

 

[Tzed250]

Reeds

Reed valve induction is geared toward an engine that must operate over a wide RPM range, and at different throttle positions. Yamaha figured out many years ago that the piston port roadrace engines made higher peak HP numbers, but suffered with poor rideability. Since chainsaws operate in a narrow RPM rage, and at WOT, the advantages of reed induction are somewhat lost. A reed valve in the intake track is actually an impedence to flow, therefore costing peak HP.

 

[amdburner]

PEST
I too have wondered about the absence of reed technology in modern chainsaws. I have thought about modifying a cylinder by adding a reed box. Someday I will attempt it. Right now I have no spare cylinders to toy with.

Also, what part of VT are you located? I am in the northwest corner in Georgia.

 

[PES+]

amdburner

check your PMs

 

[sawinredneck]

PEST stands for
Power Equipment Service and Technology

I shall re-register to avoid further confusion

I started the thread to make people think and that makes me a jackass

I know nothing it's OK

I now know better

Simmer down PEST, it's all good, the only reason RBW got so wound up is this is something that really interested him, he really likes the oldschool stuff, and tries to understand it as much as he can!!!
Nobody wants you gone, nobod wants you to reregister, it's a newbie thing, we all went through it! Should have seen how they bashed on me, or L2neck for that matter, when we first started up!! I even wonderd about ciscoguy for a while LOL!!! It just takes a bit to get the feel of everybods personality on both sides! You're comments may have been said jokingly, but were misread or interprited by us, we just need to get to know you a bit better
Grab a beer, relax a bit, nobody is nuking you, and laugh at the crazies on here, have some fun :yoyo:
Andy

 

[lesorubcheek]

Yea, please don't take offense PEST. This is a wonderful topic. I've asked similar questions regarding reed vs. piston ported designs another forum, but so far haven't received detailed answers either. It would be awesome if someone would shed light onto the real scoop on this topic.

Dan

 

[sawinredneck]

If there are members you would rather not hear from just go to their personal profile and click on 'Add username to Your Ignore List'.

It is a great feature.

Saw that comming

 

[Lakeside53]

Reed valve induction is geared toward an engine that must operate over a wide RPM range, and at different throttle positions. Yamaha figured out many years ago that the piston port roadrace engines made higher peak HP numbers, but suffered with poor rideability. Since chainsaws operate in a narrow RPM rage, and at WOT, the advantages of reed induction are somewhat lost. A reed valve in the intake track is actually an impedence to flow, therefore costing peak HP.

Absolutely correct...

 

[RaisedByWolves]

If there are members you would rather not hear from just go to their personal profile and click on 'Add username to Your Ignore List'.

It is a great feature.

How can you give advise like that when you didnt know what was said?



Hey PEST, come on man, I wasnt trying to flame you, just bring things back from the direction they were going.


You seem like a good guy, and this isint the first time Ive been taken the wrong way, but I gotta be me.


If thats not cool with you, Ill learn this and back off. If it is cool we can throw digs back and forth and have fun with it.



This is a rough place sometimes, but its full of good people who all share a love for chainsaws.


I apoligise for calling you a Jackass. Your user name is cool, lets move on, K?




Ok, just for reference sake, this is where Freakinstang comes in and accuses us of having a "Love in" or "Sausage Fest" or something of that sort. Its all good, hes a good guy.




.

 

[Chopwood]

Back on topic, I have a 3120 husky with a custom cast reed cylinder. I'll post pics when the wife gets back with the camera.

 

[RaisedByWolves]

Some of these posts got me to thinkin, I may try to find a source of thin pre made sheets of carbon fiber and make some limp torque reeds for some of my torquier saws.

I recently got a 6 shoe clutch for my 925 and the clutch is no longer the weak link, the clutch now has enough grip to drag the rpms down to around
2500 (guesstimate) and more torque would be nice right around 3-4K.


Juts have to come up with a repeatable way to test torque.

 

[sawinredneck]

Some of these posts got me to thinkin, I may try to find a source of thin pre made sheets of carbon fiber and make some limp torque reeds for some of my torquier saws.

I recently got a 6 shoe clutch for my 925 and the clutch is no longer the weak link, the clutch now has enough grip to drag the rpms down to around
2500 (guesstimate) and more torque would be nice right around 3-4K.


Juts have to come up with a repeatable way to test torque.

They have the kits out now, mainly for automotive looks stuff, so you can bake you're own carbonfiber now. Might be worth a look RBW.
Andy

 

[Lakeside53]

build your own fan wheel or hydraulic load with a variable bleed/waste-gate. Not hard to do.. Tricky to calibrate, but..

Occured to me today... while looking at my pressure washer pump.. that it would make a damn good load for my saw tester... and adjustable. I figure a 4:1 ratio chain drive is all I need!