Excessive vibration

[Atti2ude]

Jumped on the chopper tonight after several days out of town and while riding through the neighborhood noticed excessive engine vibration on decel regardless of speed. Practically shakes the entire bike each time but seems to be isolated in the engine vs. drivetrain. It was dark and I could see ignition module lights flashing (blue, red and yellow)...never noticed them before and don't know if it's related. Uncertain of what was going on so I kept the rpm's under 3 grand and the speed under 45. Weird experience. No missing, backfire or other strange noises. Just wanted to have an idea before I took it to the dealership. Thanks

 

[N8KAM]

Check your upper motor mount bolt to the frame or the two to the heads..
Flashing lights on the ign module are normal..

 

[slowrower]

Good input N8KAM, sure does sound like a lose or broken motor mount to me as well. Is the motor running fine, good idle? just bad vibration?

 

[N8KAM]

I had the same thing when i bought my bike.... Found the dealer in Nashville left both bolts out of the heads.. after doing some recall just before i picked it up. so i replaced them :up: then the bolt to the frame came loose...... :bang:
Only needed one more thing..........LOCK-TITE...:2thumbs:

 

[Gas Man]

Per Ray's suggestion.. you can also replace those 2 bolts going to the heads on that mount with longer ones... like 1/2" longer.

 

[lee]

was the vibration on decel only? when engine braking? or was it when you were applying your brakes?

 

[seatmaker]

Bolts to the head question. On mine, I noticed that there is a spot on each head where a bolt goes but don't see what purpose it serves. 1 head has a bolt in it, the front one does not. Are these used to balance the motor? Should I have one missing? Are these stupid questions?

 

[jimizee028]

mine is same way and noticed it from the second day i bought it brand new,got me puzzled but it would be kool to know why,,i like knowing WHY,,,,,,everything

 

[dogvet]

Bolts to the head question. On mine, I noticed that there is a spot on each head where a bolt goes but don't see what purpose it serves. 1 head has a bolt in it, the front one does not. Are these used to balance the motor? Should I have one missing? Are these stupid questions?

If your referring to the holes on the left side of the heads (behind the coil cover), those holes are for a knock sensor and a head temperature sensor for EFI) BDM's EFI doesn't use a knock sensor and the cylinder head temp sensor is one of the intake manifold bolts on EFI models.

 

[V]

On the heads kinda hidden by the coil are 2 holes. one has a plug the other doesn't. They are about the same size as a spark plug hole. These are for the S&S IST ignition which we do not have. I think 1 is for a knock sensor the other for a temp sensor


V

Dogvet beat me to it

 

[dogvet]

Dogvet beat me to it

Sorry VAC, I guess the caffeine has kicked in this morning!

 

[lee]

yep - both mine now used as described

 

[kirk927]

What are the torque values on these bolts. Center top bolt and the two bolts that are on the coil cover. Thanks for any help, I think mine need to be tightened. Also, should I loosen first then retorque?

 

[lee]

What are the torque values on these bolts. Center top bolt and the two bolts that are on the coil cover. Thanks for any help, I think mine need to be tightened. Also, should I loosen first then retorque?

I think its in the manual which I don't have with me right now but no doubt someone will chime in - I would take the bolts out, clean the threads, and then loctite them back in to torque

 

[dogvet]

What are the torque values on these bolts. Center top bolt and the two bolts that are on the coil cover. Thanks for any help, I think mine need to be tightened. Also, should I loosen first then retorque?

35 ft/lbs. take em out, clean em up, put some red loctite 271 on em and torque em back up.

 

[reloaderbmg]

if you do the bolts for the head, do them one at a time!