Broken Motor Mounts ???

[cuzron]

Last trip out on my 86R I noticed some vibration and it got worse and worse till I had to truck it home. I looked it over and found 4 broken mounts. ( both front and both welded ones under the motor). How normal is this and what can I do to ensure it won't happen again. I'm gonna rip it down tomorrow and order 2 new front mounts and weld in two new ones under the motor, but is there anything else I should do to keep down the vibration so it doesn't happen again? Help me fellas, I'm not sure why this happened. No other cracks anywhere on the quad and 4 mounts break on the same ride, don't sound normal to me???

[deathman53]

counter balancer could be going bad, that faily normal on a 86 frame. start by rewelding new mounts in, are you using a headsay?

[cuzron]

are you using a headsay?

Not sure what you're talking about?

[deathman53]

some people say the headstay holds the motor tigher and reduces any vibration.

[velocityatv]

I had all of them break in one day at the track. It's very common and if you jump big at all watch for the frame tube directly behind the lower motor mounts that are welded to the frame. I doubled up the lower and front motor mounts. Then, I know some people will tell you this is a little over the top but I also welded the cracks in the tubing and then welded a piece of 3/4" square stock about 6 - 8 " long, on the under side of the frame directly under the lower motor mounts. I race moto cross and I've ran a year and a half on this with no problems. Also make sure your running a head stay ( upper head brace that runs from side to side and attaches with a single bolt to the head)

[wilkin250r]

The problem isn't your motor mounts, the problem is the vibration. You counter balance could be shot, or your crank isn't true, SOMETHING inside your motor is out-of-whack.

You can re-weld the motor mounts all you want, but they'll keep breaking until you fix your vibration problem.