08 ovs tial stops pulling at 45mph

[9500blizzard]

I've been haveing trouble getting my sled to pull hard past 45mph, it'll rocket up to 45mph then it falls on its face. my a/f is 12.5, rpm is at 8000, i have 59/61 gears in it so this makes 45mph half of my top speed, anyone have any ideas?

Specs; 08 M8, 11psi, av gas, 6500ft, 162", ovs clutching

 

[RACINSTATION]

Secondary clutch is binding up. Bad bushing, flat rollers, or something else is going on. You should pull 45 with that setup on one cylinder.

 

[9500blizzard]

thats kind of my thoughts too, rollers are good, checked for spring bind, my bushing isnt the greatest, is there a tollerance for this? I just weighed my weights and they're 73 grams which seems really light but it won't pull rpm with more weight. my primary spring is 190/330, would i be able to add more weight with a weaker spring? I dont know a whole lot about clutching, thanks for your help, cheers

 

[WyoBoy1000]

does it do it in a climb or everywhere.

 

[9500blizzard]

in a climb it wont pass 45mph, on the trail it well pull hard to 45 then it accelerates really slow

 

[Tonysnoo]

pretty crazy! Did it use to work OK and now it's doing this? Or is the sled new to you and you are just figuring it out?

You gotta have something stopping the clutches from upshifting......bad rollers, stuck weight/pins, broken spider, swcondary issues like mentioned above......?


If the sled is new to you:
Maybe the tach may be off and reading too low. I ride a lot higher in elevation with about the same boost and always swing 80+ gram weight. Lighter weights don't seem to over rev, they just don't pull...kinda gets flat.

if your clutches are in good shape, you could load your weights up and see how it pulls. Good Luck!

 

[WyoBoy1000]

Sounds like a secondary issue, try a new belt. how are the motor mounts? Are your set screw in the primary weights tight and in the right spot.

 

[Tonysnoo]

One other thought

I had a big bore do this a few years back. It was a mag end starting to crack. It finally broke and was a lot easier to figure out..lol hope this isnt but???

 

[9500blizzard]

I've had the sled since new, it use to have a aero ovs kit on it and it rocked. The primary was new this year but i tried my old one this weekend just to make sure it wasent it. I tried to add 2 grams of weight today and it wouldnt pull it, was down to 7800.

 

[9500blizzard]

Primary weights and centered and move freely, i've tried new belts, belt deflection is proper. What was cracking the mag end of the crank?