07 Dragon 700 vibration..

[Hansen13]

Recently redid the motor on my 07 dragon 700 after the crank snapped off and the clutch came flying out the side panel... I have it all back together everything went smooth and took it out for a ride last week and now it has a weird vibration coming from under the tunnel.. First off I checked the drivers, they are perfect were replaced before I bought the sled last year. Then I checked the tension of the track and even did try adjusting it a bit, still nothing. Then I checked the bearing behind the cover that's underneath the secondary, it was good. (Regreased). Then I checked the wheel bearings, two uppers and the two at the back, and they're all good too. Everything in the sled is brand new including the primary now. Any ideas to what's causing this? It's terribly noticeable when you ride it.

If it helps I've double checked all my motor mounts after tightening, retorqued my primary. Even tried out a different belt. Nothing seems to be helping and it's driving me crazy!! HAS to be something simple!!!!

 

[Kraven]

Recently redid the motor on my 07 dragon 700 after the crank snapped off and the clutch came flying out the side panel... I have it all back together everything went smooth and took it out for a ride last week and now it has a weird vibration coming from under the tunnel.. First off I checked the drivers, they are perfect were replaced before I bought the sled last year. Then I checked the tension of the track and even did try adjusting it a bit, still nothing. Then I checked the bearing behind the cover that's underneath the secondary, it was good. (Regreased). Then I checked the wheel bearings, two uppers and the two at the back, and they're all good too. Everything in the sled is brand new including the primary now. Any ideas to what's causing this? It's terribly noticeable when you ride it.

If it helps I've double checked all my motor mounts after tightening, retorqued my primary. Even tried out a different belt. Nothing seems to be helping and it's driving me crazy!! HAS to be something simple!!!!

Is the vibration in synch with speed of the sled, or engine speed????

1) remove the belt- CAREFULLY and GRADUALLY give it a little throttle slowly, and see if you still have the vibration, just to rule out the engine. After that remove the clutch and re-test if need be, just be real E-Z on the throttle

2) UPPER jack-shaft bearing right next to the secondary (the one you can't grease)
(sounds like you checked the LOWER drive-shaft bearing)

3) A possible rip / (chunk hanging) out of your track to where the torn rubber is hitting the tunnel. Try rotating the track by hand and inspecting it more closely

Hope this helps

 

[mike_s]

I dont see any mention of the chaincase. They can tend to vibrate pretty bad before a chain lets loose. In any case check the tension at least, better to pull the cover and chain and sprockets to see how worn it is. Generally if one breaks it takes the case out with it.

 

[Hansen13]

Is the vibration in synch with speed of the sled, or engine speed????

1) remove the belt- CAREFULLY and GRADUALLY give it a little throttle slowly, and see if you still have the vibration, just to rule out the engine. After that remove the clutch and re-test if need be, just be real E-Z on the throttle

2) UPPER jack-shaft bearing right next to the secondary (the one you can't grease)
(sounds like you checked the LOWER drive-shaft bearing)

3) A possible rip / (chunk hanging) out of your track to where the torn rubber is hitting the tunnel. Try rotating the track by hand and inspecting it more closely

Hope this helps

I've ruled out the engine now. I will inspect the track closely and check for lugs. Any idea how I get at that jack-shaft bearing to check it? That sounds like that could be an issue. Thanks for your input.

 

[mike_s]

I've ruled out the engine now. I will inspect the track closely and check for lugs. Any idea how I get at that jack-shaft bearing to check it? That sounds like that could be an issue. Thanks for your input.

The bearing he is talking about is behind the secondary clutch. Remove the belt, grab a half inch wrench and pop the clutch off, or just grab the clutch and see if there is any movement there.

Is this a high frequency vibration or a low frequency one? A torn track lug would be more of a thump thump, a bearing or chain would be more of a buzz...

I still believe that it would be worth looking at the chain and chaincase as well, as if the chain fails you will be replacing the case also. Its way way easier to replace the chain now than both later.