Hey, guys. I need some help with a vibration issue. 1988 FLHTC. I pulled the motor last winter and did the top end, a cam (ev23) lifters, S&S super E, midwest mc electronic ignition (dyna style) coil and wires, and 38" drag pipes. I also got rid of alot of stuff on the bike to save weight and look more like a street glide. I didnt replace any motor mounts, and put the stabilizers back right where they were. The bike runs awesome, but has a pretty wicked vibe it didnt have before around 4500 rpm and up. I ordered a thunderheader and want to have the bike dyno tuned before spring, but I want to get this figured out before I spend the money. I was thinking of doing a new front mount and the rear rubber mounts. There could be a lot of things causing this, but I dont want to throw good money around chasing this. I hope someone has some suggestions on where to start. Thanks!!

 

Very wise! Let us know how things are after you have replaced them.

 

With out very expensive equipment you cannot rundown a vibration that you created.
It could be as simple as removing one bolt and replacing it with another, relocating a mirror, moving a foot peg 1/8 in. etc.

Forget about it, the "bike" does not "feel" the vibration, you do. OTOH you may set up a stress crack somewhere in the future.

 

First take your shop manual out and check the driveline alignment. Make sure you didn't over torque the front mount. Then look all around the engine, etc. to ensure that nothing is touching something it shouldn't be touching. An exhaust pipe touching the frame, etc. will transmit the harmonics of the engine to the frame causing a problem like you are having. Hope this helps.
John

 

Thanks for the input guys! I am going to get the mounts from the local dealer, then go though the alignment procedure. I've never done it, but it shouldnt be too bad if I take my time. And make sure the torque is correct. Hopefully that does it.

 

Update. I installed a glide pro front motor mount. Didn't touch the rears. Vibration problem is GONE! It still shakes a bit, but it is a Harley, but she revs up to redline, or as close as I dare to go, pretty darn smooth. Thanks guys.