Chain differences

[Upton44]

Between a 23rs 67 and a 23rs pro 67

[lxskllr]

Looks like the pro is narrow kerf...

New saw chain from Stihl! | Forestry.com

[sawguy21]

It is and needs to be paired with a narrow kerf bar.

[Upton44]

It is and needs to be paired with a narrow kerf bar.

Actually the bar on my 291 has the 23rs chain and my 261 has the pro chain and both bar numbers are identical.

[Philbert]

It will catch up with you.  A narrow kerf chain cuts a narrower slot: when the cutters are new, that may be adequate for the conventional guide bar to fit.  As the cutters are worn/filed/ground back, they become lower, and narrower, and you can start having problems with clearance.  Narrow kerf chains have been around for many years from Oregon and Husqvarna; they are just 'new' to STIHL.

Philbert

[Upton44]

It will catch up with you.  A narrow kerf chain cuts a narrower slot: when the cutters are new, that may be adequate for the conventional guide bar to fit.  As the cutters are worn/filed/ground back, they become lower, and narrower, and you can start having problems with clearance.  Narrow kerf chains have been around for many years from Oregon and Husqvarna; they are just 'new' to STIHL.

Philbert

So I guess the dealer I just bought the 261 from put the wrong chain on.as the 291 and 261 both have the exact same bars.

[Tacotodd]

Maybe. Where are you located and when did he put what bar on?
Was it a narrow kerf bar to match the narrow kerf chain? Because, you're finding out that it's going to matter.

[Upton44]

Maybe. Where are you located and when did he put what bar on?
Was it a narrow kerf bar to match the narrow kerf chain? Because, you’re finding out that it’s going to matter.

I'm located in manitoba,Canada here are the specs
Ms291
Bar# 3003 008 6613
Chain# 3637 002 0067/23rs
Ms 261
Bar# 3003 008 6613
Chain# 3690 002 0067/23rs pro 67
Just trying to find out why the saws have the same Bar but different chains and if there is going to be an issue.i also appreciate all the help.would also like to add that I purchased the 261 last week

[Tacotodd]

Let me see if any Stihl dealer on here knows. At the same time I'll ask my Stihl dealer and see what he can tell me. My end will take a day on 2. Don't give up on me, the narrow kerf chain just became available down here (from what I can infer) but, like has been shown before, I could be wrong 😑 

If it's available now, I'll switch back to .325 on my little saw and keep the 3/8 on my biguns!

[Upton44]

Thanks for the help tacotodd.my dealer is over an hour away 1 way .and phoning him I got nowhere.its clear that if both bars are the same I can put the 23rs chains on the 261 saw.

[Upton44]

Thank you for taking the time to contact STIHL Limited.  23RS and 23RSP are both .325 picth .050 gauge, so they are interchangeable between your MS291 & MS261 saws.

The new “P” designation refers to our Pro chain.  This new chain cuts about 20% faster and has reduced vibrations.


From stihl canada

[sawguy21]

That doesn't answer the question. Will the 23RSPro chain have adequate clearance with the standard bar?

[Tacotodd]

For roughly half of its cutter life.

[Upton44]

That doesn't answer the question. Will the 23RSPro chain have adequate clearance with the standard bar?
Well then why would stihl canada say its interchangeable?just trying to figure this out once and for all thank you for the reply

[Tacotodd]

It's supposed to be in the bars. You can use a normal kerf chain on a narrow kerf bar, but not the other way around.

[Upton44]

It’s supposed to be in the bars. You can use a normal kerf chain on a narrow kerf bar, but not the other way around.

Ok well when you hear back from a still guy post it here please. Thanks for your input

[firefighter ontheside]

I thought 261's came with 3/8 pitch and 291 with .325.  

[lxskllr]

261 is .325. The 026 was .325 but had 3/8 as a supported option. It doesn't appear to be officially supported in the 261, but should work equally well.

[sawguy21]

The 261 can be used with 3/8 chain such as 33RS and a shorter bar but keep it sharp and don't force the cut, it works best with .325.  I asked our local dealer about the 23RSPro, he doesn't want to be bothered with it. The saws are such a small percentage of his business he is too busy to deal with discussions about minor differences in chain.

[realzed]

All new 261's were supposed to be equipped with RS Pro chains from the factory starting late last year and into '21.
As far as I know the standard bar they would be also shipped with would be the standard 3003 .050" bar that previously had the RS type chains on them and also were .050" (this was according to Willard who first mentioned these new chains about a year ago in one of his posts here).
I have a Pro chain - but haven't installed it as I'm waiting for my regular .325 RS types to wear out and they haven't so far, but from what I'm told they are made to work with the standard bar my saw came with which is the .050" 3003 type.
It's pretty hard to imagine that Stihl, or any decent manufacturer would produce a chain that wouldn't work with the bars they also equip the saws with from new, to basically worn out from filing and normal use!
The RS Pro chain was initially introduced in Europe over a year ago in concert with the 04 Light bars to speed up the cutting ability for the 261 style of saws and apparently work very well together.
The chains have made it here to North America - the 04 Light bars not so much, so far.. but they apparently are quite light and really make an already easy to use saw a real breeze to handle and fast cutting when coupled with the Pro chain, which can often be seen of Youtube videos produced in Europe on the newer 261CM MTronic gen3 saws especially!

[Upton44]

Used this ms261 for the first time this morning .this saw rocks.very pleased.keeping my 291 for backup.

[realzed]

Original discussion regarding these RS Pro chains here:

"New" Stihl .325 NK chisel chain. in Chainsaws (forestryforum.com)