To run the 8DN on the stock clutches you will more or less end up removing the deflection adjusting screws leaving no further adjustment. Machining the secondary wil regain adjustment by allowing the clutches to come together more.
The primary mod is to get it into full shift.
To the OP: what doe your clutches look like? how much belt dust etc?
The primary mod is to get it into full shift.
To the OP: what doe your clutches look like? how much belt dust etc?
ApexGTman
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I have the same Problem, '15 RTX LE, MPI Trail kit, Ulmer Clutch kit, Red Spring 6-2, Supertips 2-0-2, 8DN belt, Gearing changed to 24/50. I think I will try what Bleedyamaha suggests about adding a washer to the back of the secondary.
Threeman03
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Let me know if that works. This is so annoying it's stupid. I have exact same set up as u
2-0-2 weights. 6-2 primary. And it's all over the place. It starts out 8850-900 running like raped ape then next thing you know it's 8400 tops for rest of day. I've put new belts on ,old belts. Etc. can't get it to be 88-9 consis no matter what I do. I've switched clutching from custom , tried bikeman weights , now tried ulmer thinking that would help dial it in. Nothing. Keep me posted.
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custom
Washer behind the secondary will change nothing!
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You might want to run your air intake outside the hood as clutches heat up and your intake sucks hotter air that might be another thing to think about. Not sure if that would affect rpm just an idea
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The inconsistency problem is not reserved to the turbo's.
I will start with my wife's sled, bought it and exchanged the Blue Silver Blue primary spring for White Pink White,(lower engagement, higher rate, same final close as stock).
Began break in, followed factory recommended break in as close as possible (that first 160 K staying under 6000 RPM is PAINFUL) up to 500 K under 8000 is better, and made it to 800 K first oil change.
Then I started clutching, added weight and added weight and added weight till weights were full, now down to 9000 max RPM and drops to 8700ish. Changed primary spring to Yellow Pink Yellow, now it"s 9170 to 9175 max RPM and drops to 8900ish and pulls, Now it will run close to my Nytro, I'm happy, wife's real happy.
Thats where 2013-14 season ended.
I liked the seating position, the ride and the handling of the Viper enough that I would give-up some speed and power from the Nytro, so I bought a carryover Viper for last season.
I followed the same break in procedure as my wife's, primary spring and all, got to 800 K oil change and I'm only making 8600 RPM, not even close to rev limiter.
Both sleds go in for the reflash, mine now starts better and idles better other than that no change, hers doesn't start as well and idles like #*$&@ but other than that runs the same as last year.
Back to clutching, changed to Yellow Pink Yellow, maybe 100 RPM better, now what, COTC seems to be working what the hell, Bought weights and a spring put them in, WTF no more RPM now more speed, if anything less responsive, now what. Back on here to see what else I can find.
I'm going to switch to the 8DN and start over, the belt is set up to were on the lift at an idle the track is rolling over at 7 KPH, lock the break and leave it run there is no belt squeal so it's about as tight as it can be. Take it out and try it, first run 8600, 125 KPH, second run 8500 about the same speed, ran it the rest of the day, every time you hit it was different, 8400 to 8700 over a 250 K day.
Back to COTC maybe it'll work better with the 8DN, NOPE, SSDD. I tried White White secondary spring, I tried 39 Deg helix i went right down to no rivets. I get RPM up but lose speed because I couldn't shift up. If I got close one day it was different the next, I have never seen a Jeckal & Hyde like this thing. End of 2014-15 season.
I installed a Hurricane power up on mine this year, FINALLY I can run with my wife's sled, I am now clutched the same I don't quite make as the same max RPM but it is finally consistent and runs like I thought it should be from day one.
SO is there anyone one here that can tell me, And a few others with the same problem why two supposedly identical sleds (same model , same year, mass produced) can be so far apart.
PS My wife's sled is still running original 8JP, this is year 3 still pulls the same RPM every time out and has no more belt dust than my 8DN.
I will start with my wife's sled, bought it and exchanged the Blue Silver Blue primary spring for White Pink White,(lower engagement, higher rate, same final close as stock).
Began break in, followed factory recommended break in as close as possible (that first 160 K staying under 6000 RPM is PAINFUL) up to 500 K under 8000 is better, and made it to 800 K first oil change.
Then I started clutching, added weight and added weight and added weight till weights were full, now down to 9000 max RPM and drops to 8700ish. Changed primary spring to Yellow Pink Yellow, now it"s 9170 to 9175 max RPM and drops to 8900ish and pulls, Now it will run close to my Nytro, I'm happy, wife's real happy.
Thats where 2013-14 season ended.
I liked the seating position, the ride and the handling of the Viper enough that I would give-up some speed and power from the Nytro, so I bought a carryover Viper for last season.
I followed the same break in procedure as my wife's, primary spring and all, got to 800 K oil change and I'm only making 8600 RPM, not even close to rev limiter.
Both sleds go in for the reflash, mine now starts better and idles better other than that no change, hers doesn't start as well and idles like #*$&@ but other than that runs the same as last year.
Back to clutching, changed to Yellow Pink Yellow, maybe 100 RPM better, now what, COTC seems to be working what the hell, Bought weights and a spring put them in, WTF no more RPM now more speed, if anything less responsive, now what. Back on here to see what else I can find.
I'm going to switch to the 8DN and start over, the belt is set up to were on the lift at an idle the track is rolling over at 7 KPH, lock the break and leave it run there is no belt squeal so it's about as tight as it can be. Take it out and try it, first run 8600, 125 KPH, second run 8500 about the same speed, ran it the rest of the day, every time you hit it was different, 8400 to 8700 over a 250 K day.
Back to COTC maybe it'll work better with the 8DN, NOPE, SSDD. I tried White White secondary spring, I tried 39 Deg helix i went right down to no rivets. I get RPM up but lose speed because I couldn't shift up. If I got close one day it was different the next, I have never seen a Jeckal & Hyde like this thing. End of 2014-15 season.
I installed a Hurricane power up on mine this year, FINALLY I can run with my wife's sled, I am now clutched the same I don't quite make as the same max RPM but it is finally consistent and runs like I thought it should be from day one.
SO is there anyone one here that can tell me, And a few others with the same problem why two supposedly identical sleds (same model , same year, mass produced) can be so far apart.
PS My wife's sled is still running original 8JP, this is year 3 still pulls the same RPM every time out and has no more belt dust than my 8DN.
Threeman03
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I'm going to run my intake outside I truly think that's the problem because mine starts out dead not 8889 and then after about an hour of riding it when the engine temp warms up that's when my RPMs drop
