Tapp blowing belts compared to stock primary

[Trailleader]

I think a team secondary on a cat is proof enough float isn’t needed
It’s impossible to float that clutch
The team setup works very well, too bad the primary doesn’t last
Why not make an offset bar
Easy to make

 

[KillerBee]

For what it worth, my problems still persist.
I did the stub shaft which was only off slightly. Still blowing belts and clutches running hot. Just had the secondary shaft machined and will attempt to further align using Knapps and Maxes method. Maybe a dumb question but can one lock down the secondary when using a belt adjuster (TP in my case).
Remains to be seen if any snow will still be around for me to test things out….. Thanks.

 

[KnappAttack]

You should be able to lockdown the secondary. Just get innovative. Either that or give up the external adjuster and just shim in-between the sheaves using old Cat reverse cam secondary shims like I did. I just keep it simple and use the shims for deflection.

I've found floating the secondary does not work as it sticks outward under power, say if you roll along at a slower speeds and grab a handful. It is floated outward at slower speeds and can't align properly on the topped while it's under power and move inwards, no matter how easily it moves on the shaft.

When belts blow, it's telling you it's not happy for some reason, either alignment or the setup/clutching recipe, or sticking clutches or clutch parts. So many things to look at.

 

[KillerBee]

Thanks Mike
secondary is spotless clean and works smoothly. Rollers are perfect. I get the float idea as you have described.

 

[snowcaine]

Title of this thread got me. I have 3 TAPP/STM combos. I've also run TAPP/stock combos. Tons of drag racing, hard pulls, back-to-back-to-back pulls. Not one blown belt. SRX has 137 1" track and 192 1.63 triggers. Cat has 137 1.25" track and 192 1.63 triggers. Winder has 146 1" track and 204 1.86 triggers. ZERO issues. If you're blowing belts, it's not because of the TAPP clutch.

Edit to add: all machines tuned 300+ hp too.

 

[1nc 2000]

Removing float from secondary

This is how mine is set up. First I set my offset with the hurricane offset tool. Second I cut the aluminum plug to be flush with the clutch hub. This is my clutch bolt. The washer next to the aluminum plug holds my clutch from floating. The two small washers are used to set my belt deflection...

ty4stroke.com

 

[KnappAttack]

Thanks Mike
secondary is spotless clean and works smoothly. Rollers are perfect. I get the float idea as you have described.

What is the setup in your secondary? Rollers? Helix? Spring and setting?

 

[KillerBee]

TP rollers, straight 35 helix, dalton b/o v2 wrapped 6-3.

 

[Trailleader]

Soften it up
While I agree on offset being something you need to check I don’t believe you can break belts at will at 270 hp
Clutch calibration off
and yes check offset

 

[1nc 2000]

Soften it up
While I agree on offset being something you need to check I don’t believe you can break belts at will at 270 hp
Clutch calibration off
and yes check

Bad offset will rip belts in half at will with stock power level.

 

[Trailleader]

I guess I’ve never seen a cat do that
Must be only yamaha
which would be similar to all the stms we have run
Still never saw this
I do agree to check it since that wouldn’t hurt and also can obviously help
The other factor here is he never had problems before
I don’t know enough about Yamaha springs to give advise but on a cat style stm I ran springs soft

 

[STAIN]

TP rollers, straight 35 helix, dalton b/o v2 wrapped 6-3.

6-3 is pretty tight with that spring/helix combo.

 

[74Nitro]

Thanks Mike
secondary is spotless clean and works smoothly. Rollers are perfect. I get the float idea as you have described.

Are the sheave surfaces perfectly straight on the primary?

 

[Trailleader]

Bad offset will rip belts in half at will with stock power level.

Bad offset will rip belts in half at will with stock power level.

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

 

[KnappAttack]

TP rollers, straight 35 helix, dalton b/o v2 wrapped 6-3.

So thats a lot of pressure on my scale. What I have found is rollers make a huge difference on things. I run Hi-Torques rollers for a reason, they roll freely both up and down and provide less pressure on my scale than anything I've ever seen. Even when the Hi-Torque rollers get worn, I replace them as the pressure to move the secondary gets too high.

The 35 helix is fine with that spring wrapped at 90 on the Hi-Torques, maybe too much pressure on the other rollers. The difference on new Hi-Torque rollers vs worn Hi-Torque rollers is 80-90 lbs difference on my scale at the top end which is huge. This is a tremendous strain to the belt from over pinching and bind. Fresh Hi-Torque rollers offer a much smoother RPM line on the data logs, so you know the up and down shift is smoother and more consistent with less pressure on the belt. Maybe something to think about and try the Hi-Torque Rollers. Also make sure the bushings are in good shape in the secondary too, when they get loose, they will bind.

You should get that secondary locked into place however and not float it.