Rim sprocket

[Ashmoore]

I’ve got a stihl 661 and when I brought it they asked if I wanted a 8 tooth rim sprocket.
I asked if it was safe and they said yes so I purchased it with the saw.
My question is this would it make a huge difference if I got a 9 tooth rim sprocket for my saw and if there any information I need to know before going a head with it.
I use a 20” bar and I’m cutting red gum some black box and old fence post which are box wood with the carbide chain
Any help would be much appreciated
Cheers

 

[cuinrearview]

I think @redbull660 may have some insight on your question

 

[Ashmoore]

I think @redbull660 may have some insight on your question

Cheers

 

[redbull660]

as you go up in sprocket size you gain chain speed BUT you lose torque. Also a 9pin is fine for racing. But to easy to throw a chain doing anything else.

Knowing how hard the aussie timber is I'd hzzard a guess 8pin 20" is just about right.

 

[Ashmoore]

as you go up in sprocket size you lose toruqe. Also a 9pin is fine for racing. But to easy to throw a chain doing anything else.

Knowing how hard the aussie timber is I'd hzzard a guess 8pin 20" is just about right.

Cheers redbull,I was guessing that was the case with a 9 tooth and I’ll keep using the 8
Seems to cut nice and plenty of torque.

 

[redbull660]

if you want more chain life. I'd consider doing an 8pin 20" .404 .063 full skip chain.

 

[Ashmoore]

if you want more chain life. I'd consider doing an 8pin 20" .404 .063 full skip chain.

Ok I’ve seen on EBay these ported exhaust you can put on the 661 to make it a dual ported exhaust.
Question
Is there any performance increases or loss
Is it harmful to the saw

 

[redbull660]

don't put it on the front cover. well unless you want to lose torque. needs to be on the other side, opposite of the stock port.

 

[redbull660]

Ok I’ve seen on EBay these ported exhaust you can put on the 661 to make it a dual ported exhaust.
Question
Is there any performance increases or loss
Is it harmful to the saw

 

[Ashmoore]

don't put it on the front cover. well unless you want to lose torque. needs to be on the other side, opposite of the stock port.

Cheers
I was curious of any change of prof

 

[Huskybill]

On the larger cc saws I go up one pin on the rim, add the skip tooth chain. The change over to .404” chain is a good choice too. The teeth are longer so the chain lasts longer.

With the smaller cc saws I just go up one pin on the rim but keep the chain razor sharp so the rpm stays up without loading the saw more. If skip tooth chain isn’t available.

Note, The first thing I change on a saw is to get rid of that sprocket and go to a rim. Rollerizing the bar and chain/rim cuts effortless.

 

[sundance]

On the larger cc saws I go up one pin on the rim, add the skip tooth chain. The change over to .404” chain is a good choice too. The teeth are longer so the chain lasts longer.

With the smaller cc saws I just go up one pin on the rim but keep the chain razor sharp so the rpm stays up without loading the saw more. If skip tooth chain isn’t available.

Note, The first thing I change on a saw is to get rid of that sprocket and go to a rim. Rollerizing the bar and chain/rim cuts effortless.

@Huskybill I like rims, but help me out with how it makes any difference in how the chain runs.

 

[Ted Jenkins]

I go opposite from Husky. When ever possible I try to slow the chain speed down. The chain last much longer and much much faster. Any chain that is running fast will need much more attention. Especially on 404 chain and I never use skip chain. I cut a lot of dry Oak which is hard on chains so this approach has worked for me. What Husky is doing is not wrong, but it seems to be working for him and his needs. Thanks