Viper Ltx Se clutch help/opinions

[superb]

The COTC setup works, the sled needs at least 700 miles on it to start pulling the rpm's. Mine really came alive when I installed a Dalton 46-40 helix, at 6 and 1.

 

[skidooslayer687]

I wonder if that's what's going on with mine, that helix is just to steep off the start...

 

[Studroes144]

I wonder if that's what's going on with mine, that helix is just to steep off the start...

It is steep, but shouldn't be too steep, I ran a 50/46 last year and as long as weights are loaded properly it works awesome.

 

[skidooslayer687]

We'll see today, going out with buddy again to compare against his nytro, last weekend I had the BSB spring with the 8jp belt and the white secondary spring... Now running the OPO primary spring, pink secondary spring with the weights loaded different so I'll post back later with results!

 

[skidooslayer687]

So I went out yesterday with a couple buddies up to white lake, one buddy has the nytro, it's got the same mods as mine does, and the other buddy has a 1200 with a header and can on it... Snow conditions weren't the greatest, lake was fairly hardpack but temps were warm, snow was somewhat "sticky" so naturally we all lined up... Buddy with the nytro can't hookup as well doesn't have the studs, I came out of the hole first with the bomby maybe a ski length behind, I held everybody off until basically high mid range, the. Buddy with the nytro passed me and the doo slowly crept by, that was race 1, so then pulled cover off and marked primary to check shift out and lined up again... Same thing, took them both out of the hole till high midrange then was passed... I must add when I was being passed my speedo was saying around 155km/h so I would say more top end.... Checked primary after this race, full shift out! 1/4" below top of primary! This is good, was never getting this with the older setup and 8jp belt. Also I think I've got the Rpms figured out a lot better, comes out of the hole hard, but Rpms seem to stabilize at around 8350-8450 then tractor there way up to 8900-9000 and stay there, now going by what ulmer has posted in the dyno results I've read this is right where the motor makes its ponies.

Lined up one more time for a race, took them both out of the hole and held it the entire race! Top speed I saw though was 158 km/h though which is not overly exciting, buddy on the nytro was seeing I belive 103 mp/h on gps. However this race was long! I would say in around the 3/4 of a mile mark.... Just seems like this is all the viper has, gonna try tinkering with some suspension stuff, I wanna break that 100 mph mark! Lol

 

[sixstringorsnow]

Your sled is going to work 10 times better if you get it to rev up to 8800 right away and not fall back. When you get it, you will smoke your buddies.

 

[Studroes144]

Your sled is going to work 10 times better if you get it to rev up to 8800 right away and not fall back. When you get it, you will smoke your buddies.

It's very true! You're losing 2+ sled lengths when it lugs along like that.

 

[skidooslayer687]

What would you guys recommend then for getting the rpm up? Because I can't seem to get it to go to 8800 and hold there no matter what I've tried it always wants to lug then tractor back up

 

[Studroes144]

6-2 wrap, weights only loaded in the tip, even if u tap the rev limiter once on launch it's ok, it's still faster than lugging it at 8300.

 

[skidooslayer687]

Spring is wrappe at 6-2, which has seemed to control the lug a lot more, clutch temps went up a bit but still can hold my hand on them for 15-20 seconds after a hard run

 

[Studroes144]

Do as much testing and tuning while racing other comparable sleds as you can, once you get it right, you'll know. I still think that heel weight is really hurting you and causing it lug on launch

 

[stingray719]

Update. Well with lots of trial and error I believe I have solved my problem. My secondary spring is worn out and need a new one. The big thing I learned was when I got home and started to play with the nitro clutch. They put the demo belt on my sled by mistake. So I went home and set up my secondary for the 8dn belt. Needless to say my rpms were worse and my shift problem amplified. The only thing we didn't change between the demo and mine in the swap was the belt ride high in the secondary. I have been running my belt too tight from day one. So I believe for some reason the belt height is screwing up my shift. I can't prove it yet because I'm waiting for my new secondary spring to come in and they needed the demo back together for a customer. The height in the manual is 1.5mm. So you may want to check and make sure its within spec.

Also the 8dn belt on the viper reached yamaha and they sent a bulletin to the dealer warning them not to use it on the viper it is not a fix. Apparently the belts have a 3 degree difference in the angle on the sides. Just though I would share what I heard. I still think the 8dn belt works better.

Im going to take a break from clutching until next week. It's going to be a beer and buff weekend and wait for the snowstorm that is coming this weekend. I will post back next week and let you know if that completely fixed my problem when my new spring comes in.

I would like to give a shout out to my dealer Atlantic Motoplex who went above and beyond for me. I have had the best service here. I have been associated with a lot of great dealers in the past, but they are by far the best. Any time I have had a problem with something they always made sure I was on the snow for the weekend.

"Also the 8dn belt on the viper reached yamaha and they sent a bulletin to the dealer warning them not to use it on the viper it is not a fix" Translates to = OMFG we have a boatload of 8JP belts in stock!!!!!

 

[sixstringorsnow]

"Also the 8dn belt on the viper reached yamaha and they sent a bulletin to the dealer warning them not to use it on the viper it is not a fix" Translates to = OMFG we have a boatload of 8JP belts in stock!!!!!

LOL To funny.

 

[sixstringorsnow]

Was able to go for a 53 mile run tonight and a lot has changed since I started clutching this year. Started out with COTC worked well, but couldn't get a straight shift. COTC was not the reason for this. Now after my visit to the dealer and figuring out some stuff, here is my experience. Take it for what it is worth, some will think I'm crazy some may not, but I am still at aw. So I have put all my clutching back to stock, except I have a 4.5 in my mid and a 3.6 in the tip. stock springs, stock helix and belt. It is by no means the fastest set up, but I have a straight shift. I still haven't got my new secondary spring yet and only changed my belt ride height to make sure it was in spec 1.5 mm above to .05 mm below sheave. I am at 1.5mm above. All I can say is it made a huge difference in how my sled performed. I had a straighter shift and if and when it dipped its rpm, it recovered a lot quicker. Not like a tractor pull like I was getting before, it recovered in seconds. Also I had it going the fastest its ever gone on groomed trail, 95mph. I would like to point out that the trail was groomed last night and set up really well with our cold temps -19C. My philosophy of clutching was I would tighten the rear belt height as tight as I can get it until the sled would just creep. It seemed to work on my other sleds, but not this one. If little changes in the suspension and other things can effect these sled dramatically than why can't this. Just thought I would share what I have figured out with my sled. It may save someone some time and aggravation, because I know I have 4600 miles of it.

 

[cannondale27]

Was able to go for a 53 mile run tonight and a lot has changed since I started clutching this year. Started out with COTC worked well, but couldn't get a straight shift. COTC was not the reason for this. Now after my visit to the dealer and figuring out some stuff, here is my experience. Take it for what it is worth, some will think I'm crazy some may not, but I am still at aw. So I have put all my clutching back to stock, except I have a 4.5 in my mid and a 3.6 in the tip. stock springs, stock helix and belt. It is by no means the fastest set up, but I have a straight shift. I still haven't got my new secondary spring yet and only changed my belt ride height to make sure it was in spec 1.5 mm above to .05 mm below sheave. I am at 1.5mm above. All I can say is it made a huge difference in how my sled performed. I had a straighter shift and if and when it dipped its rpm, it recovered a lot quicker. Not like a tractor pull like I was getting before, it recovered in seconds. Also I had it going the fastest its ever gone on groomed trail, 95mph. I would like to point out that the trail was groomed last night and set up really well with our cold temps -19C. My philosophy of clutching was I would tighten the rear belt height as tight as I can get it until the sled would just creep. It seemed to work on my other sleds, but not this one. If little changes in the suspension and other things can effect these sled dramatically than why can't this. Just thought I would share what I have figured out with my sled. It may save someone some time and aggravation, because I know I have 4600 miles of it.

So you are using stock 8JP and are at 1.5mm above and it works well? Then you say your Philosophy of tightening belt till it creeps does NOT work on this sled? Can you clarify?