Thunder Products (Big Venom Viper kit) with Heavy Hitters

[SnoNinja]

"Take 4"

After adding one more .4g washer to the middle hole, RPM dropped to 8800-8900 at WOT at 95 MPH consistently. However, still hitting the rev limiter hard from a launch until 30 - 40. Yes, I am spinning the track on hard packed snow. Ski's in the air and cutting a nice even launch trench until I get to mid range and the front end settles down a bit. Tonight I will add a 1/4" set screw in the heel to control RPM at launch and see what that does during tomorrows test rip. Will also remove one of the 2 thin washers from the middle if adding heel weight doesn't affect the top end RPM. Still wrapped at 6-1 on the secondary, and will go to 3-3 if heel weight doesn't resolve the launch control.

Shagman and I talked about the weight transfer differences between the LTX and the XTX as primary contributors to the over rev at launch. being uncoupled, the XTX can transfer weight deeper than LTX because of limits of our coupling. Once my ski's come up (a lot higher than they used too due to the added traction of the 1.6 cobra), I am sure that the front of the skid is getting light and that is causing some of the track spin.

"Take 4" set-up:
8DN
blue-silver-blue primary spring with glide washer each side
3/4" set screw heel
3/8" head aluminum and (2) thin washers in middle
7/16" head steel in the tip
6-1 secondary wrap with TP Big Venom blue spring

 

[murdered141]

"Take 4"

After adding one more .4g washer to the middle hole, RPM dropped to 8800-8900 at WOT at 95 MPH consistently. However, still hitting the rev limiter hard from a launch until 30 - 40. Yes, I am spinning the track on hard packed snow. Ski's in the air and cutting a nice even launch trench until I get to mid range and the front end settles down a bit. Tonight I will add a 1/4" set screw in the heel to control RPM at launch and see what that does during tomorrows test rip. Will also remove one of the 2 thin washers from the middle if adding heel weight doesn't affect the top end RPM. Still wrapped at 6-1 on the secondary, and will go to 3-3 if heel weight doesn't resolve the launch control.

Shagman and I talked about the weight transfer differences between the LTX and the XTX as primary contributors to the over rev at launch. being uncoupled, the XTX can transfer weight deeper than LTX because of limits of our coupling. Once my ski's come up (a lot higher than they used too due to the added traction of the 1.6 cobra), I am sure that the front of the skid is getting light and that is causing some of the track spin.

"Take 4" set-up:
8DN
blue-silver-blue primary spring with glide washer each side
3/4" set screw heel
3/8" head aluminum and (2) thin washers in middle
7/16" head steel in the tip
6-1 secondary wrap with TP Big Venom blue spring

Hope it goes better for you, I've already tried the 1/4" set screw with the 3/4" and it didn't change anything, hoping 3-3 will be the way to go, if not then I guess the next step is the evo flash with raised limiter.

 

[Janne339]

Important to clean the clutch from belt dust. Wash with breake cleaner

 

[STAIN]

Have you tried a helix change?

 

[SnoNinja]

Important to clean the clutch from belt dust. Wash with breake cleaner

Clutch is clean.

 

[SnoNinja]

Hope it goes better for you, I've already tried the 1/4" set screw with the 3/4" and it didn't change anything, hoping 3-3 will be the way to go, if not then I guess the next step is the evo flash with raised limiter.

I hope so too. You are running a bit more HP than I am, but we need to get this under control. 3-3 wrap will let it pull deeper into the secondary quicker and that should drop RPM on launch. As said, work in progress.......

Between me, NosPro and Shagman, we will get this right and will post solution for the benefit of all who are running this kit.

 

[stingray719]

Important to clean the clutch from belt dust. Wash with breake cleaner

Plastic pieces in the clutch use anything besides soap and water at your own risk.

 

[SnoNinja]

Hope it goes better for you, I've already tried the 1/4" set screw with the 3/4" and it didn't change anything, hoping 3-3 will be the way to go, if not then I guess the next step is the evo flash with raised limiter.

Shagman, Nos-Pro and I are working on a solution......no need for panic spending.

 

[jakehayamaha]

Hey guys. Just thought I'd share my setup, as it seems to be working for me. 2014 RTX SE

Mods- Ulmers performer package from last year-- K&N filters, muffler, and fuel controller.

Clutching- Big Venom kit with weights at 48.1 (Lonn setup for me), secondary spring at 6-2, 911 cover, and Gates belt with the stock shims on secondary replaced with ones that came with belt from Thunder Products.

From the testing I've done in mostly 8" of powder- smooth engagement, pulls hard all the way to WOT, have yet to hit rev limiter- max RPM 9260. Seems great from 0-80 as I haven't been able to open it up much more than that until I can get on some hard pack.

 

[cannondale27]

Hey guys. Just thought I'd share my setup, as it seems to be working for me. 2014 RTX SE

Mods- Ulmers performer package from last year-- K&N filters, muffler, and fuel controller.

Clutching- Big Venom kit with weights at 48.1 (Lonn setup for me), secondary spring at 6-2, 911 cover, and Gates belt with the stock shims on secondary replaced with ones that came with belt from Thunder Products.

From the testing I've done in mostly 8" of powder- smooth engagement, pulls hard all the way to WOT, have yet to hit rev limiter- max RPM 9260. Seems great from 0-80 as I haven't been able to open it up much more than that until I can get on some hard pack.

Are all you guys with issues using the Gates? That belt makes a huge difference. Always brought rpms down vs 8dn or 8jp for me.

 

[SnoNinja]

Hey guys. Just thought I'd share my setup, as it seems to be working for me. 2014 RTX SE

Mods- Ulmers performer package from last year-- K&N filters, muffler, and fuel controller.

Clutching- Big Venom kit with weights at 48.1 (Lonn setup for me), secondary spring at 6-2, 911 cover, and Gates belt with the stock shims on secondary replaced with ones that came with belt from Thunder Products.

From the testing I've done in mostly 8" of powder- smooth engagement, pulls hard all the way to WOT, have yet to hit rev limiter- max RPM 9260. Seems great from 0-80 as I haven't been able to open it up much more than that until I can get on some hard pack.

6-2 worked fine in the powder, but over rev at launch on take off 0-40 on hard pack. Have got that cured with 3-3 wrap for the most part, now just need to fine tune center and tips again for the 3-3 wrap. Need to get back 100 rpms on the upper end. Hard thing is I ride both on and off trail, and secondary wrap is different for both conditions. Heavy snow and deep powder likes 6-2 better so engine isnt lugging moving heavy snow, and trails 3-3 is better for launch control. I am working on clutching to the 3-3 so that I can just adjust secondary on days when I am going boondocking. Will post best result when we get it. Close now.

 

[SnoNinja]

Are all you guys with issues using the Gates? That belt makes a huge difference. Always brought rpms down vs 8dn or 8jp for me.

Not yet, and trying not to if we can help it. I know it grips better and brings rpm down, but we don't want to have to go there if we don't need to. It is an option if we can't get down where we need to, but close now.

 

[SnoNinja]

Will run "Take Seven" tomorrow in the daylight. Don't really like doing clutch test runs down a not so smooth unplowed but snowmobile packed road in the dark. Take six had positive results with only hitting the rev limiter once when breaking traction at launch. You could feel the skid hit full weight transfer and the blow traction right before it hits the rev limiter. If I could keep traction, no rev limiter. Issue here I think is that the 1.6 tracks hooks up so much better than the Rip Saw II that the weight transfer can't keep up. On the hard pack, I seem to be running out of weight transfer before I run out of wheelie.

We will solve it.

 

[NOS-PRO]

Hey guys....I'm back!

Colorado was a hoot and I'm glad to see everyone helping out one another here

Just a note....those running the Gates belt will have lower rpms than the guys running the 8DN. About 200-300 difference. It's because the clutches grab the Gates belt better.

SnoNinja - great conference call between us and Shagman last night, glad it helped you with the rev limiter on take off, now take some weight out of the tip and middle to get your rpm's back to where they need to be. Great part about these weights is the adjustability

 

[murdered141]

Hey guys....I'm back!

Colorado was a hoot and I'm glad to see everyone helping out one another here

Just a note....those running the Gates belt will have lower rpms than the guys running the 8DN. About 200-300 difference. It's because the clutches grab the Gates belt better.

SnoNinja - great conference call between us and Shagman last night, glad it helped you with the rev limiter on take off, now take some weight out of the tip and middle to get your rpm's back to where they need to be. Great part about these weights is the adjustability

Hey Terry can you post the part # of the Gates belt, my buddy work's for a distributor , I can get them dirt cheap.