372 xp weird sound at half throttle

[Grapple Man]

hi all,
hope everyone is well. my question today is on my new 372 xp. i have probably 10 tanks of gas through it, and have this problem. at about half throttle it sounds like the saw is hitting the limiter and trying to govern itself. the saw has been muffler modded, and i am getting ready to put a non limited coil on it. i have adjusted the carb, but haven't turned it up yet. it is running WOT at around 12, 700 to 12,900. not wanting to get it too hot before it is good and broken in. just looking for some insight. the saw cuts great and will make the sound while in the cut and out. but it does not seem to be loosing any power in the cut while the sound is occuring. thanks for all your help.


Joe

 

[TRI955]

Saws are not made to be ran at half throttle. All or Nothing!!!opcorn:

 

[Grapple Man]

Saws are not made to be ran at half throttle. All or Nothing!!!opcorn:

yeah i know, but you go past half throttle on your way to "all or nothing", and also do do all my limbing at full throttle, and i listen to my saws a lot to make sure they are tunned rite and running well.

 

[Grapple Man]

Saws are not made to be ran at half throttle. All or Nothing!!!opcorn:

and p.s. your avatar is great.

 

[CentaurG2]

How often do you cut at half throttle?? Sounds to me like the saw is just cold. Sometimes they can stall if cold but you feel a power lag. Why did you modify the muffler on this saw and not turn up the RPM??

 

[B_Turner]

4 stroking like sound?

 

[Grapple Man]

How often do you cut at half throttle?? Sounds to me like the saw is just cold. Sometimes they can stall if cold but you feel a power lag. Why did you modify the muffler on this saw and not turn up the RPM??

like i said the saw doesn't have a lot of tanks thru it so just my personal preference. it will get turned up very soon. and probably ported and polished as well, but like i said previously it has nothing to do with the temp, i don't believe, but keep the ideas coming.

 

[Grapple Man]

4 stroking like sound?

no, it more of a i know this is going to sound bad, but a ting ting ting sound. like the saw is hitting the limiter, but when you pull on into the throttle to WOT the power is rite there and no misses in it whatsoever.

 

[Grapple Man]

what do you think guys, could it be from the muffler mod?

what you thinking brad, i see i caught your attention which i was hoping to do.

 

[CentaurG2]

The only thing I can think of is something rattlin’ in the muffler or loose on the saw. Does the saw “lack” power when making the noise or is it just a noise??

 

[Grapple Man]

and ment to say earlier i don't do all of my limbing at WOT.

 

[Grapple Man]

The only thing I can think of is something rattlin’ in the muffler or loose on the saw. Does the saw “lack” power when making the noise or is it just a noise??

yeah i was thinking that also and have dismantled everything and can't find a darn thing loose. and as i said earlier there is definitely no power loss.

 

[TRI955]

and p.s. your avatar is great.

Thanks.....

 

[CentaurG2]

Probably just a harmonic due to the muffler mod. I would turn the saw upto 13.5K and not worry about it.

 

[B_Turner]

tin tin like the clutch rattling?

At what rpm is this happening (like a tach reading to make sure it is not on the limiter- as I would expect that to be a different sound)?

 

[056kid]

your saw is fine. 2 strokes make all kinds of funny noises when you dont dog em. And unless your saw is running really lean, there is going to be that noise pretty much all the time except when its loaded down.

 

[Grapple Man]

tin tin like the clutch rattling?

At what rpm is this happening (like a tach reading to make sure it is not on the limiter- as I would expect that to be a different sound)?

yes exactly and thanks for the better description. and havn't put the tach on it for that reading but i would expect it happens from about 8 to 9K

 

[Grande Dog]

If you have it at an RPM where it's teetering between the high and low speed circut, it'll change RPM's without moving the trigger.

 

[rngrchad]

My 372 at mid throttle sounds like it is four-stroking, or hitting a rev-limiter. Normal for these saws. I don't notice this on my Stihl's but do notice it on this 372. Just want to make you feel better. Don't worry about it as mine does exactly what your describing but it cuts like a banshee at WOT. I don't see any need for a black-box on my saw.
-Chad