SR Viper MTX turbo clutching!

[Srxspec]

Had the opportunity to ride & tune on a SR Viper MTX 162 LE with the Yamaha/MPI turbo for 2 full days and have a clutching package ready to go! Very responsive feel down low with great midrange & top end pull! Package will work on 153 & 162 sleds with turbo! We will be working with the stock SR Viper MTX models as well! Ulmer Racing 605-387-2833 or Srxspec@Gwtc.net

 

[MOUNTY]

What elevation/snow conditions etc.... did you test in?

 

[tmk50]

They were in the Snowy Range WY.

Allen - I met your crew on Saturday morning and they (Jeff?) had just put a new setup on the blue/orange turbo LE.

Cody let me take it for a quick rip before they went out riding for the ride that day. How close was that setup to what you guys ended up going with?

 

[loudelectronics]

I have a MCX 190 and need clutching in the worst way. I have the white spring, nytro mtx helix, gwg primary and 8bu weights. I recently just dropped my gearing to 21/49 and way out to lunch. Hits the rev limiter right away.

Would your clutching work for this or is the gearing totally different in the 2015 mtx so clutching would not be the same? I do not have the time to figure this out on my own. Just want my sled to work.

 

[Srxspec]

What elevation/snow conditions etc.... did you test in?

8500 to 10,000 + feet. Pretty good powder conditions overall, best riding we've ever had in the Snowy Range.

How close was that setup to what you guys ended up going with?

Close, slight primary spring change yet, but weight settings remained the same.

I have a MCX 190 and need clutching in the worst way. I have the white spring, nytro mtx helix, gwg primary and 8bu weights. I recently just dropped my gearing to 21/49 and way out to lunch. Hits the rev limiter right away.

Would your clutching work for this or is the gearing totally different in the 2015 mtx so clutching would not be the same? I do not have the time to figure this out on my own. Just want my sled to work.

We used a different primary spring, helix, and weights than what you have listed. I can help tune you in using some of your components if you want or set you up with what we had, with your gearing lowered it should be very very close.

 

[tmk50]

What elevation/snow conditions etc.... did you test in?

8500 to 10,000 + feet. Pretty good powder conditions overall, best riding we've ever had in the Snowy Range.

How close was that setup to what you guys ended up going with?

Close, slight primary spring change yet, but weight settings remained the same.

Good deal. I think I would be happy with that setup that we rode, that's great that you improved on it. The snow has been very good this year, for April riding it was great last weekend.

 

[akvector]

I have a MCX 190 and need clutching in the worst way. I have the white spring, nytro mtx helix, gwg primary and 8bu weights. I recently just dropped my gearing to 21/49 and way out to lunch. Hits the rev limiter right away.

Would your clutching work for this or is the gearing totally different in the 2015 mtx so clutching would not be the same? I do not have the time to figure this out on my own. Just want my sled to work.

It is hard to clutch because there is so much out there that can work. My advice for what you have is get rid of the GWG spring with 8bu weight that spring is too stiff. Try a Yellow Pink Yellow if you are willing to experiment.

 

[loudelectronics]

Its quading season now so not going to do anything with it till next year. No snow to experiment on either. Will catch up with Ulmer Racing in the fall.

akvector,

on our last trip at 8,000' I pulled the stock spring out and put the gwg in from my nytro MTX. It actually helped pull the RPM a few hundred and helped out. The softer spring was a dog. With my gearing change I could likely go back now as it is really over revving. Not sure I am crazy about the 8BU weights either. I want to try something else to compare. I need to get an array of clutch components to try but my time in the mountains is limited and just want it to work. Whatever I do at home is not going to work in the deep snow in the rockies. I will look at the ypy spring though and thanks for the advice.

 

[Srxspec]

The YPY will not give you the throttle response and "snap" that you need in the mountains, in my opinion.

 

[stingray719]

I have a MCX 190 and need clutching in the worst way. I have the white spring, nytro mtx helix, gwg primary and 8bu weights. I recently just dropped my gearing to 21/49 and way out to lunch. Hits the rev limiter right away.

Would your clutching work for this or is the gearing totally different in the 2015 mtx so clutching would not be the same? I do not have the time to figure this out on my own. Just want my sled to work.

It is hard to clutch because there is so much out there that can work. My advice for what you have is get rid of the GWG spring with 8bu weight that spring is too stiff. Try a Yellow Pink Yellow if you are willing to experiment.

And there are more than a few of us run grn-wht-grn WITH a spacer and it rocks. Please try ideas you say will not work before expressing a "fact" please....or at least preface your comment as an opinion.

Coming to the mountains 8FS or 8FP weights and grn-wht-grn with 2mm shim and add rivets for final rpm. Or buy Ulmers kit. You don't need to experiment.

 

[akvector]

I have a MCX 190 and need clutching in the worst way. I have the white spring, nytro mtx helix, gwg primary and 8bu weights. I recently just dropped my gearing to 21/49 and way out to lunch. Hits the rev limiter right away.

Would your clutching work for this or is the gearing totally different in the 2015 mtx so clutching would not be the same? I do not have the time to figure this out on my own. Just want my sled to work.

It is hard to clutch because there is so much out there that can work. My advice for what you have is get rid of the GWG spring with 8bu weight that spring is too stiff. Try a Yellow Pink Yellow if you are willing to experiment.

And there are more than a few of us run grn-wht-grn WITH a spacer and it rocks. Please try ideas you say will not work before expressing a "fact" please....or at least preface your comment as an opinion.

Coming to the mountains 8FS or 8FP weights and grn-wht-grn with 2mm shim and add rivets for final rpm. Or buy Ulmers kit. You don't need to experiment.

You are correct if he put the 8fs back in he would be fine with the GWG the 8bu is too light of weight in my opinion for the gwg. I actually have set up a few with the 8bu and ypy and 14.5 rollers all with great success. I spent money on clutch kits that just did not work so I started playing.

That being Said I never did get one from Ulmer and he has great products so I am sure he would get him in the right direction.

 

[turbo800]

Is there an easy way to convert Yamaha's (kg/mm) spring chart #'s to (lbs/ft) something comparable to Doo, Cat, or Poo?

My first problem is they use Preload (kg) for their engagement rpm, instead of a 2 given forces @ distance.........take Green/White/Green for example.
Preload 45 (kg)
Spring rate 2.75 (kg/mm)
Total Force 136 (kg @33mm)
Free Length 89.8 (mm),
Wire Diameter 6.0 (mm)


A similar Doo spring with the same wire dia. and free length would be close to a 80-260, one of their softest available. I realize there is other things to consider like # of coils, diameter of the spring....etc


Seems everyone including aftermarket measures their springs at different heights...

CAT: 2.562" (65mm) and 1.312" (33mm)

Poo: 2.500" (63.5mm) and 1.190" (30mm)

Doo: 2.913" (74mm) and 1.614" (41mm)

 

[Srxspec]

KG to lbs conversion is very easy.

45 KG = 99 lbs (KG x 2.2 = lbs)

136 KG = 299 lbs

Yamaha Preload is measured at 2.888"

Yamaha Total force is measured at 1.593"

 

[turbo800]

KG to lbs conversion is very easy.

45 KG = 99 lbs (KG x 2.2 = lbs)

136 KG = 299 lbs

Yamaha Preload is measured at 2.888"

Yamaha Total force is measured at 1.593"

Perfect!

So your saying the second rate of the spring is NOT at 1.299" (33mm) instead its 1.593" ?(40.46mm)

Thanks!

 

[fc8464]

Where you able to do any testing at low elevation? thanks Fred