Hello,

Yesterday during a ride with my daughter a problem happened with my KVF 400. Suddenly, there was a lot of grinding noise and a lot of vibration comming from under the ATV. After a quick visual inspection, nothing appeared broken. The front axle is spinning correctly and in the rear, nothing unusual.

The engin was still running smoothly. However when going forward or on reverse there is still a lot of noise and vibration.

As I was deep in the wood, I headed back home at low speed. While going downhill, I tried with the tranny in neutral to see if the noise will go away, but no... The noise remained and the vibration is still there.

I noticed that the vibration is more present over bumps or while turning.

Now, my ATV is back home in my garage. I am about to do a surgery to find what the problem is. Any recommendation where to look first?

Cheers,

Martin

 

Well, I decided to start in the back.

I removed the whole drivetrain. I think I found my problem. Both rear axle bearings were totally destroyed! This allowed a little bit too much travel for the rear shaft probably putting pressure on the u-joint. Still the u-joint looks pretty good. No slack at all... I checked the back differential and found no sign of wear. I will replace the rear bearings and seals, put everything back together and see how it goes...

Cheers.

Martin

 

Just to close this thread...

I brought my ATV back to the woods last week-end. Did a two hour run of hard trail and everthing works perfectly.

The problem was the two bearings.

Cheers.

Martin