Clutch offset STM's and stock

[SuperTurbo]

Maybe this could some?
I have STM's and found the stock clutches was the same with factory offset, may be a isolated satiation but you may want to check yours if you have a belt breaker.
I still had issues with the STM's as stock, hot "burn" hands... snap, explode belts, etc..
STM uses (Yamaha factory offset) only they have you measure offset different with their clutches than the factory user manual however it is the same exact offset as stock.
YOU MUST TAKE OFF THE CLUTCH GUARD to visually check if the belt is riding straight!!
Put aside the digital vernier's and use the ole' eyeball measuring device.
Long story short I removed a factory and STM supplied shims AND milled .125" to push clutch inward both STM and factory secondary to get it riding straight, clutches are warm not boiling this hopefully should fix "my" issue.
Some vids.

Removed all shims still wasn't enough.

Float to find sweet spot

Beautiful

 

[blue fun]

Good info. Thank you!!!!!!!

 

[Soupy]

I'm with ya, posted about this a couple weeks ago. So, if measured with the stock setup, what is your offset now? Most people are saying it should be at the high end, 2.41 inches. I can't imagine you moved it .553 over from stock, did you? I'm trying to get an estimate of how much further inward that my secondary needs to go.

My only other thought was that maybe the secondary doesn't open, or shift inward, as fast when it has a load as opposed to being on the stand.

 

[SuperTurbo]

I'm with ya, posted about this a couple weeks ago. So, if measured with the stock setup, what is your offset now? Most people are saying it should be at the high end, 2.41 inches. I can't imagine you moved it .553 over from stock, did you? I'm trying to get an estimate of how much further inward that my secondary needs to go.

My only other thought was that maybe the secondary doesn't open, or shift inward, as fast when it has a load as opposed to being on the stand.

Yeah all the factory shims plus we milled .125"
I would ignore what everyone is telling you to be at!
I hated to pull the guard "rivets" in two spots rest is screws and and nut, I know.. brand new machine it was my last resort but all the measures everyone was saying even STM said no way I sent them the vid. PULL the gaurd brother and look/watch take video so you can actually see what it is doing, what do you have to loose?

Remember the diff is STM measurments on how they have you measure their clutches.

 

[Soupy]

Yeah all the factory shims plus we milled .125" so thats almost .25" inch in..from factory .
I would ignore what everyone is telling you to be at!
I hated to pull the guard "rivets" in two spots rest is screws and and nut, I know.. brand new machine it was my last resort but all the measures everyone was saying even STM said no way I sent them the vid. PULL the gaurd brother and look/watch take video so you can actually see what it is doing, what do you have to loose?

I have video of mine but slow mo so I think harder to see offset, had the guard off, measured with indicator, etc. Just wondering, have you ran it with a load and verified lower clutch temps after riding it? What belt you running? I blew 3 damn belts last wknd alone!

 

[SuperTurbo]

I have video of mine but slow mo so I think harder to see offset, had the guard off, measured with indicator, etc. Just wondering, have you ran it with a load and verified lower clutch temps after riding it? What belt you running? I blew 3 damn belts last wknd alone!

Ran on stand no load, I've broke all the belts 8J's 8D's every Gates. Just running it on the stand the clutches got hot, after the fix they were cool to warm so it made a difference.

 

[Soupy]

Ran on stand no load, I've broke all the belts 8J's 8D's every Gates. Just running it on the stand the clutches got hot, after the fix they were cool to warm so it made a difference.

Thank you sir.

 

[SuperTurbo]

I realize this is STM clutches the moral of the story is take the guard off, look at it.. maybe yours could be this bad? or not at all just look at it.

 

[nightrunner06]

is it safe to say that any person would benefit from getting a floater and pulling all the washer/ shims off of the jackshaft? obviously one step further would be to do what you did.

I realize this is STM clutches the moral of the story is take the guard off, look at it.. maybe yours could be this bad? or not at all just look at it.

 

[Motorhead]

Someone use to make a simple clutch offset tool.
My buddy bought one for his SRX back in the day. I have used it on most of my Yamaha’s to check clutch lineup.
I’m sure he still has the set, it also came with a blue adjustable center to center measure. Came in handy for when I rebuilt and had to reinstall the 2 smokes.

Simply held it on the back of the primary and watched where the offset bar met with the secondary. Left the bolt off the secondary so you could pull the secondary away and then bring it in and watch where it makes with the secondary.

Anyone making something like that for the winders? They are tough to line up without taking much apart.

 

[SuperTurbo]

Someone use to make a simple clutch offset tool.
My buddy bought one for his SRX back in the day. I have used it on most of my Yamaha’s to check clutch lineup.
I’m sure he still has the set, it also came with a blue adjustable center to center measure. Came in handy for when I rebuilt and had to reinstall the 2 smokes.

Simply held it on the back of the primary and watched where the offset bar met with the secondary. Left the bolt off the secondary so you could pull the secondary away and then bring it in and watch where it makes with the secondary.

Anyone making something like that for the winders? They are tough to line up without taking much apart.

Problem with the "tools" it may not work for "yours" yeah its generalizes all machines but not all sleds are created equal..
Pull the guard video it, yours my be fine by site but eliminate the possible issue I have.

 

[**sj**]

whats the old saying...the offset is off somewhere....either at the beginning of the shift sequence or the end..

Yeah all the factory shims plus we milled .125"
I would ignore what everyone is telling you to be at!
I hated to pull the guard "rivets" in two spots rest is screws and and nut, I know.. brand new machine it was my last resort but all the measures everyone was saying even STM said no way I sent them the vid. PULL the gaurd brother and look/watch take video so you can actually see what it is doing, what do you have to loose?

Remember the diff is STM measurments on how they have you measure their clutches.
View attachment 134763

how many shims were present ? also....Id like to see you do the same with the oem clutches (since you have the guard off) this would be very telling as even .200+- seems like allot..any chance?

 

[Soupy]

Someone use to make a simple clutch offset tool.
My buddy bought one for his SRX back in the day. I have used it on most of my Yamaha’s to check clutch lineup.
I’m sure he still has the set, it also came with a blue adjustable center to center measure. Came in handy for when I rebuilt and had to reinstall the 2 smokes.

Simply held it on the back of the primary and watched where the offset bar met with the secondary. Left the bolt off the secondary so you could pull the secondary away and then bring it in and watch where it makes with the secondary.

Anyone making something like that for the winders? They are tough to line up without taking much apart.

To what offset measurement would the tool be made? That's the question that I see. If made to yamaha's specs, it doesn't resolve anything, measuring the stock offset is a relatively easy process. From what I see, the question is how should the offset be set? And I don't mean by measurement because by eye my secondary seems to still be too far outward, even with all shims removed, just like the OP.

 

[**sj**]

obviously yam engineers have specs they know works...however, welcome to the procross and arctic cat...weve been working with this chassis since 2012' ....and yes Im sure the build is better than ever...back then...no two sleds were the same specs when measured...and stuff moves after being measured.....now its much better...but there still might be a tad of this going on...

 

[Soupy]

obviously yam engineers have specs they know works...however, welcome to the procross and arctic cat...weve been working with this chassis since 2012' ....and yes Im sure the build is better than ever...back then...no two sleds were the same specs when measured...and stuff moves after being measured.....now its much better...but there still might be a tad of this going on...

It's too bad they can still shred a belt at will. Its like picking up right where I left off when I stopped snowmobiling 20 years ago.