Rim or Chain Sprocket, which?

Arborist Forum

Help Support Arborist Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

WRW

Addicted to ArboristSite
. AS Supporting Member.
Joined
Jan 13, 2002
Messages
6,497
Location
Partlow, Virginia
Take a saw with a rim and start it and then flop it over so you can see the rim and clutch. Whether at idle or hittin' the throttle... trust me, you will see side to side movement. It might not be much but there will be movement. Now loosen the chain a tad and do the same thing... then watch it move.

Gary

OK, I tried it and the only thing moving side to side was the washer. I don't doubt you or your eyes, but it just hasn't happened for me. BTW, I loosened the chain till some of the tangs were out of the bar groove.
 
GASoline71

GASoline71

Mr. Nice Guy
Joined
Jul 12, 2005
Messages
9,663
Location
The Great Pacific Northwest
:dizzy: :dizzy: :dizzy: :censored:



Lots of saws do - sorry Gary, you were waaaay off there.......:givebeer: :givebeer: :givebeer:

I have just never run any rims with outboards... I ain't sayin' they don't exist... just never used or seen one here. :)

Gary

OK, I tried it and the only thing moving side to side was the washer. I don't doubt you or your eyes, but it just hasn't happened for me. BTW, I loosened the chain till some of the tangs were out of the bar groove.

It's prolly because all I have are those crappy Stihls... LMAO...

Guess it depends on the... well hells bells... I have no idea.

Gary
 

rxe

ArboristSite Guru
Joined
Jun 7, 2006
Messages
789
Location
UK
Two additional points:

1) Using rims makes having spares easier. As long as I have a .325, a 3/8 and a .404 rim in the spares box, I'm good for all my saws. I don't need to worry about specific drums.

2) For old saws where spares are scarce, having a rim means that you don't need to worry about sprocket wear. It took me nearly a year to track down a new sprocket for an 07S - now that I have a rim/drum for it, I never need to worry again. I'll just stick a .404 rim on it when the current one wears out.

On outboard rims/drums - my 070s and 090 all have outboard, and all are running rim/drum.
 
huskydave

huskydave

Addicted to ArboristSite
Joined
Mar 7, 2007
Messages
1,506
Location
Ontario Canada
The one bad thing about a rim is it is less efficient at transfering power to the chain. The guys that race have spursprockets machined for their saws to stay competitive but the rim is a much better choice for the average user.
 
scotclayshooter

scotclayshooter

Addicted to ArboristSite
Joined
Nov 25, 2007
Messages
3,306
Location
Scotland
The one bad thing about a rim is it is less efficient at transfering power to the chain. The guys that race have spursprockets machined for their saws to stay competitive but the rim is a much better choice for the average user.

Any pics of a modded spur sprocket?
are they modded or built from scratch?
 
huskydave

huskydave

Addicted to ArboristSite
Joined
Mar 7, 2007
Messages
1,506
Location
Ontario Canada
I don't have a pic but I have been reading up and a lot of them use the spur sprocket for racing. I had never really thought much about it but the rim sprocket is not always the best setup. I would consider using a spur setup on an underpowered saw. The ones I have seen were made from sctatch using one piece of steel. The spursprocket has less drag and some guys even drill relief holes around the center of the bore.
 
Last edited:

Latest posts

Top