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Tapp blowing belts compared to stock primary

So you can blow a belt instantly on a stock powered sled
Are the clutches sideways or one of those backwards low angle helix?
I really have never heard of this
Maybe in 2012 on an 1100 with a motor sideways but a 998
I’m serious I’m asking cause the cats don’t do this
You have 1mm rollers I am guessing
Any weight added
How are the ramps in
Any chance something is off there like two different next to each other rather than opposite of?
I think there’s too much grab in primary and secondary and they are fighting
There are all kinds of 600 and 700 hp cats not doing this
This was back in 17 on the first year winder.
Now I just put a new belt on every year for piece of mind. Dont blow belts running 300hp.
 

Does anyone have update numbers for offset for using Tapp with Stm secondary for sidewinder and for cat??
 
i posted this on previous post.... i have done 10 diff ways of measure.... using an xs825 belt, the inner TAPP sheave peak to outer STM sheave peak where belt runs is 52-52.5 mm, ..... Cat with the XS829/827 belt is 53-53.5 mm.
 
Trying to play catch up with all these new threads as life has moved at warp speeds the last couple years andI just haven’t had the time to keep up. That said I would definitely listen to what Knapp has to say as he has forgotten more than what most of us have learned over the years. I’d like to add from my experience measuring offset per Yamaha instructions that a TAPP with a stock secondary offset should fall within 59.1 to 58.7mm. I haven’t blown a belt with the TAPP yet running big power in 4 seasons. We want to avoid belt slip at all cost and over grab the belt if anything which is actually very hard to do.
 

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Yamaha is @1mm narrower soo xs825 is 52 peek to peek with TAPP and BOSS mine with xs829 was 53 -53.5 TAPP/BOSS/STM... this is all based off perfect aligned STOCK clutches,.... offset using old method =1.530, keeping all this equal and accounting for sheave thickness differences.... this is where the peek to peek comes into play.
 
Yamaha is @1mm narrower soo xs825 is 52 peek to peek with TAPP and BOSS mine with xs829 was 53 -53.5 TAPP/BOSS/STM... this is all based off perfect aligned STOCK clutches,.... offset using old method =1.530, keeping all this equal and accounting for sheave thickness differences.... this is where the peek to peek comes into play.


I think you should measure with straight edges at rear of drive and front of driver for a more exact measurement
 
I think you should measure with straight edges at rear of drive and front of driver for a more exact measurement
that is yamaha's factory way of measuring, but when your dealing with dif diameter and diff thickness of sheaves as well if aftermarket clutch sits further on snub... etc... soo the factory way doesnt wrk, this is where i came up with peek to peek as it eliminates all diameters and thickness off sheaves..... i originally set up a perfect offset that had no heat or belt wear at all, then took that peek to peek measurement, then used a conventional adjustable (SLP) offset tool to measure from outer driven sheave to centre hub at fixed sheave of primary. 1.530"(38.9mm) ... then removed and installed TAPP, measurement was 1.550"(39.4mm), the tapp sat .020 furter in on snub, soo the sec had to be moved in .020, after this the peek to peek stayed the same at 53mm(2.09"), then i remved the stock sec and installed STM.... the thickness of the STM outer sheave was .080(2mm) thicker making offset 1.610 leaving peek to peek at 53mm. belts run cool n no dust, now when your running yamaha width belts the offset.... peek to peek is reduced by 1-1.5 mm
 
That is Yamaha's factory way of measuring, but when your dealing with different diameter and diff thickness of sheaves as well if aftermarket clutch sits further on snub... etc... so the factory way doesn't work, this is where I came up with peek to peek as it eliminates all diameters and thickness off sheaves..... I originally set up a perfect offset that had no heat or belt wear at all, then took that peek to peek measurement, then used a conventional adjustable (SLP) offset tool to measure from outer driven sheave to center hub at fixed sheave of primary. 1.530"(38.9mm) ... then removed and installed TAPP, measurement was 1.550"(39.4mm), the Tapp sat .020 further in on snub, soo the sec had to be moved in .020, after this the peek to peek stayed the same at 53mm(2.09"), then i removed the stock sec and installed STM.... the thickness of the STM outer sheave was .080(2mm) thicker making offset 1.610 leaving peek to peek at 53mm. belts run cool n no dust, now when your running Yamaha width belts the offset.... peek to peek is reduced by 1-1.5 mm


I understand what you are saying...

But, I think you should convert YOUR measurements to how Yamaha measures to maintain standardization...
 
I understand what you are saying...

But, I think you should convert YOUR measurements to how Yamaha measures to maintain standardization...
sooo that would be 62.5-63.5 mm outside to outside. 2.45-2.49" .... this is for TAPP and STM only cuz thicker sheaves
 
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