Sprocket life expectancy...

[Dilz]

Just a wondering about the life expectancy of drive sprockets. When i was first taught about using saws a rough rule for replacements was 3 chains to a bar - 3 bars to a sprocket. Based on chains and bars getting worn through use rather than abuse. 

 

Had look at 261 at a company, its about 18months old - the sprokect was really worn - my guess is the chain has been run at the wrong tension too much,

a 550 has  a worn sprocket as well but that saw had the misfortune of being handed to a very special kind of worker to use as his own saw as everyone got annoyed with him wrecking all the saws and just leaving them back on the shelf. 

A 440 thats been with the company a good few years and seen a lot of use,  hasn't had a sprocket replaced on it and the one that was original is in good condition. 

 

Now is this a case of user causing the wear or are some sprockets just lasting longer?  maybe built of things other than oriental tin? 

 

 

[spudulike]

The general rule is that all MS261s and MS362s that come in get a new sprocket kit. All others get a new rim or a new spur sprocket now and then.

I still don't understand why the 261s and 362s eat sprockets - I believe it is a cunning plan by Stihl to make money on their Satan's creations. I think only one 261 escaped my rule in a good number of saws!

If the end of the spur gear has indentations then it is time to swap it!

The MS261 must be one of the worst sounding saws - the exhaust note goes right through my head!

[Richard Thompson]

21 hours ago, spudulike said:

 

The MS261 must be one of the worst sounding saws - the exhaust note goes right through my head!

I'll second that. bloody loud saw to play with all day 

[Stubby]

Just now, Richard Thompson said:

I'll second that. bloody loud saw to play with all day 

Try a Spud ported 372 ..........

[Richard Thompson]

5 minutes ago, Stubby said:

Try a Spud ported 372 ..........

I'd love too but the 261 is a high pitched whine 

[spudulike]

Andys really thumps, the 261 just whines like a nagging woman!

[Khriss]

My old rule of thumb is,

3 files to a chain

3 chains to a bar/sprocket

3 bars to an overhaul.k

 

( to guys who think the bar should last the life of a saw- but then in their hands that's usually 1 8months ;P )

[Dr Stihl]

Stihl MS261 sprocket problems should now be a thing of the past, new rim sprockets were introduced late 2016 and no problems since, unless the crank was worn by the previous sprocket. 

[Mick Dempsey]

On 2/4/2018 at 09:21, Khriss said:

My old rule of thumb is,

3 files to a chain

3 chains to a bar/sprocket

3 bars to an overhaul.k

 

( to guys who think the bar should last the life of a saw- but then in their hands that's usually 1 8months ;P )

What do you mean by overhaul?

[outonalimb]

19 minutes ago, Dr Stihl said:

Stihl MS261 sprocket problems should now be a thing of the past, new rim sprockets were introduced late 2016 and no problems since, unless the crank was worn by the previous sprocket. 

+1 . From a very reliable Stihl source the clutch drums were the problem all along (a problem with the metallurgy) now resolved.