my XTX setup, ride and review

[Apex1958]

Nos will this setup work on stock 137" Viper?

 

[stingray719]

Nos will this setup work on stock 137" Viper?

Yes, the issue is the stock weights and primary spring in ALL Vipers. The Green-white-green with 2 mm spacer is the key, and of course adding a flat or close to flat weight profile to properly use the Viper torque and obtain proper RPM.

Cheap fix, spring is $26.00 dollars here. And of course a set of weights.

 

[TD Max]

Mike, stock rollers, 8FP weights empty, no grinding or polishing.... G/W/G primary spring with a 2 mm spacer is 3,100 engagement. It's by far the best setup for taking off and pull. I want to try the 8BU weights and see where that gets me....but I hate to say it....but I believe the season is over.

This is "if" I was able to get back to Munising and do some more testing. I would put a 43 straight helix or maybe a 45/41 with pink set at 3-3 and add some tip weight to get my maximum rpm around 8,800 with the 8FP weights.

I need to post the videos cause proof is in the video of me damn near running into my Nytro when my son and I set up our races and I gave him 4 lengths each time. I could have gave him 6 lengths and still catch him in less than 1/8 or 3/4 mile.

Too bad the season is ending I'd really be interested in seeing what the timer said compared to your last session.

Now we need to merge this concept with clutch machining and possibly gearing down like Ulmer was discussing in his thread.

 

[STAIN]

Who sells spring spacers? Is the 8FP weight a stock Apex weight?

 

[stingray719]

Who sells spring spacers? Is the 8FP weight a stock Apex weight?

Yamaha sells spring spacers, but I took an old spring and cut the last coil off and flattened it by grinding high spot down and that was right at 2mm. Not sure which sled 8FP came on but you can see the specs and profile in the FAQ here at this site.

Green-white-green helped but the added spacer is what REALLY woke mine up. 8FP does not have the "bump" on the bottom of the ramp the Viper stock weight does so no overevving at take off.

 

[NOS-PRO]

Nos will this setup work on stock 137" Viper?

Yes, the issue is the stock weights and primary spring in ALL Vipers. The Green-white-green with 2 mm spacer is the key, and of course adding a flat or close to flat weight profile to properly use the Viper torque and obtain proper RPM.

Cheap fix, spring is $26.00 dollars here. And of course a set of weights.

Yes, exactly what Stingray said

 

[NOS-PRO]

Mike, stock rollers, 8FP weights empty, no grinding or polishing.... G/W/G primary spring with a 2 mm spacer is 3,100 engagement. It's by far the best setup for taking off and pull. I want to try the 8BU weights and see where that gets me....but I hate to say it....but I believe the season is over.

This is "if" I was able to get back to Munising and do some more testing. I would put a 43 straight helix or maybe a 45/41 with pink set at 3-3 and add some tip weight to get my maximum rpm around 8,800 with the 8FP weights.

I need to post the videos cause proof is in the video of me damn near running into my Nytro when my son and I set up our races and I gave him 4 lengths each time. I could have gave him 6 lengths and still catch him in less than 1/8 or 3/4 mile.

Too bad the season is ending I'd really be interested in seeing what the timer said compared to your last session.

Now we need to merge this concept with clutch machining and possibly gearing down like Ulmer was discussing in his thread.

That was one of the things I wanted to do was purchase an overdrive sheave from Hauck yet this year.

All I can say is if I wasn't hitting the rev limiter and it would have been hard pack.....I would have saw 106-108 for how it was pulling. But I was definitely hitting the rev limiter and still seeing 97 on loose snow.

Would have loved to bring the timer along and set it up

 

[NOS-PRO]

Who sells spring spacers? Is the 8FP weight a stock Apex weight?

Yamaha sells spring spacers, but I took an old spring and cut the last coil off and flattened it by grinding high spot down and that was right at 2mm. Not sure which sled 8FP came on but you can see the specs and profile in the FAQ here at this site.

Green-white-green helped but the added spacer is what REALLY woke mine up. 8FP does not have the "bump" on the bottom of the ramp the Viper stock weight does so no overevving at take off.

I made my own spacers where I work, Yamaha does sell them. As far as the 8FP weights??? I had them in the bottom of my clutching box.....removed the rivots and put them in. I don't remember what they came out of my old RX1's or my Apex?

 

[STAIN]

I might have the weights. I don't have the G_W_G spring (45kg/136kg) but I do have a Dalton Green/black which is a little stiffer on the bottom(57kg) and a little softer on the top(129kg). This might cure the need for a spring spacer AND get rid of the over rev on top. Waht did your weights weigh empty?

 

[NOS-PRO]

67 grams

I think that spring will be damn close if not right on

 

[stingray719]

I might have the weights. I don't have the G_W_G spring (45kg/136kg) but I do have a Dalton Green/black which is a little stiffer on the bottom(57kg) and a little softer on the top(129kg). This might cure the need for a spring spacer AND get rid of the over rev on top. Waht did your weights weigh empty?

Good for a test, but the gwg with spacer puts an immense amount of pressure on top and I believe that is part of the fix. GWG alone helped but the spacer is what really made this work. Might take a spacer and put in with Dalton spring, high take off speed but should pull like well after take off. Please do try and let us know.

 

[STAIN]

Stingray--did you use stock helix? Don't know if I can get my hands on a 47-40. I have one Ulmar helix but have to measure the angle.

 

[stingray719]

Stingray--did you use stock helix? Don't know if I can get my hands on a 47-40. I have one Ulmar helix but have to measure the angle.

I used stock, but NOS PRO tried several diff ones I will let him answer that.

 

[NOS-PRO]

Stain, the stock 43 straight will hit the rev limiter unless you are on extreme hard pack.

Ulmer is a good helix to run but set your pink spring at 3-3 with either helix

Another thing is my belt has quite a few miles on it, if you have a new or newer 8DN, give it a try, it might be right at 8,900 for ya!

 

[NOS-PRO]

Video of me darn near ramming my Nytro

Gave my son 4 lengths and before letting off I was 2 lengths in front of him.

https://www.youtube.com/watch?v=JeiNuxIomcE

This was proven many times over and over

With the stock viper primary and 47/40 helix with the Pink set at 3-3, I would get my Nytro about 2 lengths so this setup is working great! My Nytro is picked 144 down the center and has a newer well broken in belt. The Nytro sees 100+ consistantly on the speedo

Thanks again Bill!!!