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Lots of testing and believe we have the offset nailed down

Thanks for the explanation and reminder. But this assumes you had proper deflection to start with? Or is the washer behind secondary is so thick that removing same thickeness shims is always needed to have proper deflection?
With the Sidewinder secondary clutch belt deflection being controlled by the front washers (stock).

So if you machine off the secondary clutch on the back, you need to remove washers or machine the aluminum spacer to match. (this is if you are using stock stuff).

If you are using an aftermarket adjuster...then you can just dial it in.
 

I think some confusion is being caused by washers BEHIND the secondary on the jackshaft/up against the cir. clip(OFFSET) and the washers inside the stock "PLUG" that goes inside the outside of clutch while inserting the clutch bolt. One of these washers is what determines the OFFSET.. The other determines belt deflection(plug). Or maybe im just reading things wrong but thats what it seems like.
 
I think some confusion is being caused by washers BEHIND the secondary on the jackshaft/up against the cir. clip(OFFSET) and the washers inside the stock "PLUG" that goes inside the outside of clutch while inserting the clutch bolt. One of these washers is what determines the OFFSET.. The other determines belt deflection(plug). Or maybe im just reading things wrong but thats what it seems like.
It gets confusing for people.... I get calls daily about float and offsets.

Wish Yamaha just left the 3 bolts on the back of the secondary.
 
Funny people don't read the owners manual.
It explains it in there.

We here at Thunder Products Clutching are here to help.

It gets confusing the way it's written (that is why they ask)
But on another note, the info from the internet warriors is where the bad information comes from. (Had a guy telling me I was wrong about the float because he saw it on the internet that it should have float. Until he saw it for himself how it actually worked, then he realized and said "guess you can't believe what you see on the internet....LOL)
 
Does anyone have any offet numbers for Tapp Primary/ Stm secondary (sidewinder) (arctic cat) as well as Tapp primary and team secondary on the cats???
 
soo i like to measure from inside peek of primary sheave where belt rides to outer peek of secondary sheave where belt rides, this eliminates sheave thickness variances amongst different clutch manufacturers..... if you run a XS825 belt, its 52-52.5mm peek to peek, for xs829/827 belt its 53-53.5mm....
Every man of clutch may have thicker or thinner sheaves.... this method eliminates all those variables as long as your using same belts as its only concentrating on where belt rides.
 

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With all the tuned Sidewinders (belt blowers) coming into the shop, we needed to do some intensive testing as these "belt blowers" need to be a thing of the past. Using a precision ground bar and depth mic, I started to really get down to the nitty-gritty on this issue.

Belt blower #1 (2020 SW LTX studded track)
3 belts in 115miles. Nothing but heat from belt and clutches. Offset was 61.2mm with 1 shim. 300 TD tuned with Daltons.
After machining 3.5mm off of the back of the secondary, with 1mm shim and the circlip, the offset now was 58.7mm.
After numerous back to back runs, basically riding the sled like an a$$hole (owners own words), the belt showed a little "chipping" on the top cogs, one side only. But, no blown belts and this was 150-200 miles.
Took out the shim and butted up against the circlip, the dimension is 57.7mm and no issues. The owner is happy and has well over 500 miles on his belt as of last week.

Belt blower #2 (2017 SW RTX non-studded track)
3 blown belts on 1 ride, puppied the sled back to the trailer with an old Yamaha 8DN. Offset was 60.9mm. Precision EFI 280 tune and Thunder Products Clutching. Got a call saying he's dropping of the sled at my shop and wanted it just like Belt blower #1.
Machined 3mm off his secondary, offset is now 57.8mm and after a good weekend, no more belt issues.

Belt Blower #3 (2017 SW BTX with 153" 2.5 track)
Usually not a belt blower, but could blow a belt on command when full throttle. Offset was 59.9mm...no shim and against circlip.
TD tuned, with all the tunes including race tunes.
Machined 3mm off of the secondary and with a thin shim, the dimension is 57.8mm with 1 shim. No issues so far.

Belt blower #4 (2019 SW tuned with RCMP?)
Blew belts on command. Clutches always hot and not happy with clutching setup. Installed Thunder Products Clutching Big-V setup and did some offset checking, he is now "catwalking" his sled down fields he could never do before.

3 more sleds in the works at the shop.... 2 of them with Hurricane bundles running 300 horse and 1 Precision EFI 280 that were set between 57.5-58.0mm. Will be updating this thread when we have more info.

P.S. there are so many more out there that we have told to run this offset and know of a few that have been able to hold it wide open for long periods of time without blowing belts.

Post here is it is working for you
Did the stub shaft move? Usually after blowing a belt the stub shaft will need to be reset,we're they all checked
 
soo i like to measure from inside peek of primary sheave where belt rides to outer peek of secondary sheave where belt rides, this eliminates sheave thickness variances amongst different clutch manufacturers..... if you run a XS825 belt, its 52-52.5mm peek to peek, for xs829/827 belt its 53-53.5mm....
Every man of clutch may have thicker or thinner sheaves.... this method eliminates all those variables as long as your using same belts as its only concentrating on where belt rides.
Using your method mine measures only 50mm. Haven't had any belt blowing problems but I haven't really beat on it too much. Secondary does get some heat after a pull. Took the beltguard off and ran it up on the stand and eyeballed it as it shifted to the top and the belt looks like its running pretty straight. this is with a pro 4, 3 arm primary and the stock team cat secondary . hard to believe I'd have to shim the secondary out 3mm more. It has a .090 and .030 shim in it now that would have to be doubled
 
Using your method mine measures only 50mm. Haven't had any belt blowing problems but I haven't really beat on it too much. Secondary does get some heat after a pull. Took the beltguard off and ran it up on the stand and eyeballed it as it shifted to the top and the belt looks like its running pretty straight. this is with a pro 4, 3 arm primary and the stock team cat secondary . hard to believe I'd have to shim the secondary out 3mm more. It has a .090 and .030 shim in it now that would have to be doubled
Now that being said, ive got an 8.4" primary and 11.25 sec diameter.... with the taper extending out a little further from centre line.... this might account for the extra 1-2mm, is your aleo for a xs825 yamaha belt... because it would measure with my bigger set up 52mm, it your 3 arm is 8"and sec is 11" that might explain peek to peek being 50-51mm
 
Now that being said, ive got an 8.4" primary and 11.25 sec diameter.... with the taper extending out a little further from centre line.... this might account for the extra 1-2mm, is your aleo for a xs825 yamaha belt... because it would measure with my bigger set up 52mm, it your 3 arm is 8"and sec is 11" that might explain peek to peek being 50-51mm
I’ll have to check the dia but it’s a xs827 cat belt , stock cat secondary
 
soo heres the measurements i had for PERFECT alignment with stock clutches after using team alignment bar then converging to standard measuremnet bar

From inner sheave @ hub of primary to the outter machined surface of BOSS (old method of measuring)= 1"530=@39mm 0r 52.5mm peek to peek team clutchs

Took team off and placed TAPP on

From inner sheave @ hub of TAPP to outter machined surface of BOSS = 1"550.... so TAPP sits .020 in more on crank.
soo take .020 shim out from BOSS and bring measurement back to 1"530.

now peek to peek with bigger diameter TAPP and BOSS is 53mm or 2.086... so now this extra .5mm would explain the diff in diameter of TAPP is .400 larger.

Now took off BOSS and put the STM on that has slightly larger diameter and also sheave thickness of BOSS is .180 vs STM is .260

Soo to use old style measuring, that would equate to 1.610 hub to outer sec sheave which still came in at 53mm- 53.3mm peek to peek TAPP to STM with slightly larger STM.
 
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Now that being said, ive got an 8.4" primary and 11.25 sec diameter.... with the taper extending out a little further from centre line.... this might account for the extra 1-2mm, is your aleo for a xs825 yamaha belt... because it would measure with my bigger set up 52mm, it your 3 arm is 8"and sec is 11" that might explain peek to peek being 50-51mm
Looks like my pro4 primary measures 8.25” and stock secondary 10.75”
 
Did the stub shaft move? Usually after blowing a belt the stub shaft will need to be reset,we're they all checked
I checked every sled I worked on, visual, with a feeler gauge and by measuring from the end of the snub shaft to the bearing (on the sleds that came into the shop, not the ones I was working with on Facetime or Messenger). I took everything into account when the test was going on to make sure what was needed to fix these belt blowers.

Being a machinist and Quality Manager for years, everything got checked to ensure all the sleds that had the same belt blowing issue was going to match the other sleds in the test. I'm very anal when it comes to measuring..... Plus, to make sure that information, is valid and true, before I post.
 
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