Engine Vibration

[mcaf29]

WTF? First I gotta say my shee has so much power I couldn't imagine what it would be like with porting in the spring. It sounds pretty cool too, cause I let my buddy ride it (only one I trust) and I couldn't believe how good it sounded. Everyone was commenting on it BUT... and here it comes. If its at an idle, and I blip the throttle or just rev it up the whole shee vibrates. It shakes the frame and rattles. So my obvious concern is a few things.

 

Can a rich jetting cause this vibration? I think I'm really rich on the needle.

 

I replaced the stock flywheel with a Ricky Stator Flywheel and its the one with the stronger magnets. This seems to be the obvious answer but I want to give Ricky the BOTD that its not this brand new flywheel. Its just such a pain in the ass to take my propegs off the get to the flywheel I'm hoping its the jetting.

 

The even bigger pain in the ass would be if it were my brandy new +4 mm welded LR stroker crank. Since I did all the mods together it makes it hard to destinguish which one it is. All the motor mounts are tight too.

 

So if jetting can cause this it should go away. If it doesn't I can switch flywheels, then if that doesn't work where do I go from there. Do I just deal with it cause the motor runs great. Do I have to pull the crank and have it checked (will Wiseco warranty it?). I really do not want to go back into that bottom end right now. I was really careful on evything I did so I don't think its anything I did in there.

 

I guess another possibility is could my new dyna ignition be the cause? I'm running the stock curve for now, so maybe its causing it to not fire at its optimum point therefore I get vibration.

 

I need this fix quick so I can hide it from my friends, they already jump all over me cause all of the down time.

[PassionRE]

First guess would be the flywheel is out of balance. 2nd guess is crank is out of phase, just slightly is enough. Try yhrowing your stock flywheel back on and see if it helps...Jim

[mcaf29]

I'm gonna do the flywheel switch to check to make sure. So you're saying I have to split the cases in order to have the phase checked (if flywheel checks out)? Will Wiseco replace it? Will they pay for labor cause I really don't have time to do this again!!!

[JKJK]

i had a similar situation with mine after a topend rebuild.at idle+above until power band,it would vibrate+shake like it was way out of ballance.i checked every thing that i could think of +it checked out.i was truely stumped! so i got on the bhq+started asking questions.after many great sugestions+cenerios,banchetta had a theory about dried out cluch disks after a lower end douching.(tranny flush) so i tipped the quad on its side so all the tranny oil would flow into the cluch cover+saturate the cluch assembley.i believe that is what fixed it.vibration gone! give it a try,can't hurt.

[blk02banshee]

Mine vibrates bad, too. It's only at lower RPMs, but it's so bad, that when I rev it, and the Rs come down, the handlebars look like a blur. It blows all my lights, too! I noticed it when I had my lights on, and was waiting for my buddy to catch up, and revved it a couple times, and on the second rev, when the Rs came down, the light burned out at the peak vibration. At high RPMs it is smooth as can be. It did that ever since it was new, but it seems to have gotten worse.

[PassionRE]

mcaf29, the crank halves are phased 180 degrees from each other. You can ck this using a degree wheel and dial indicators, definately not a "quick" task but it can be done without disassembly of the motor, try the flwheel first. Are you sure all the motor mounts are tightened properly?...Jim

[mcaf29]

Thanks for all the replies