why does rear end "drop" and not spring back up?

[ragdoll]

2008 Apex LTX GT 40th. JUst had the rear shock rebuilt a few weeks ago. Today I noticed it sitting squat, and when I lift the rear bumper to pull it up to it's normal riding height, it just drops down again.

Any ideas anyone? I have to admit, this crap Yamaha suspension is really getting me pizzed

 

[darv]

Check your sag it should be 40-45 mm maybe the preload on the spring is not right

 

[TBay Sledhead]

I had the same problem 3 yrs ago, took the rear skid all apart and checked. Never did figure it out, the problem just went away.

 

[Fusion]

My '09 did/does the same thing - mostly when it's packed with about 30-40 lbs of ice after sled sits after riding.
I talked to the dealer, a very knowledgeable sort, and he said ride height is controlled by the spring and ride comfort by the shock.
I concluded it was the spring on mine was too soft, so installed the 6.5 kg/mm spring a few months ago.
When I head up north tomorrow I intend to adjust my sag in to soften it up some, as I expect this new spring will be considerably stiffer.
Not sure if it's the imagination or what, but the sled sure seems to sit higher after the the new install.
As somebody said previously, on the stock spring for that sled, I would sit by sag/sit-in to the stiff side and see if it helps.

 

[copo427ss]

Is the sled sitting level on the ground? Skis are not on dollies or under the track?

 

[ragdoll]

Is the sled sitting level on the ground? Skis are not on dollies or under the track?

Sled is in a nice warm level garage, but is on dollies, what diff wud that make?

 

[KevinS]

Is the sled sitting level on the ground? Skis are not on dollies or under the track?

Sled is in a nice warm level garage, but is on dollies, what diff wud that make?

If your front skis are raised on dollies but the track is sitting on the floor the suspension will react the way you are describing. This isn't unique to Yamaha. All sleds will do this. I believe this is related to coupling.

 

[copo427ss]

Correct on coupling Kevin. Ragdoll, put your sled flat on the concrete with no dollies and it should be sitting normal then.

 

[Daranello]

It's all coupling. My apex does the same. Take it off the dollies and problem gone

 

[ragdoll]

Thanks guys, seems to have done the trick!

Still doesn't compute to me though, as both skis and the rear were up on dollies, so the sled was essentially "level"

 

[Daranello]

Front has nothing to do with it. It's all about the rear skid coupling

 

[Irv]

Thanks guys, seems to have done the trick!

Still doesn't compute to me though, as both skis and the rear were up on dollies, so the sled was essentially "level"

Glad you got it figured out Mike.

There is usually a couple posts a season from peeps asking the same question.
It is always surprising to them once other's here tell them to remove the dollies.

I don't quite understand it either, but it does make a difference whether they are on dollies or not.

Who did you have do your shock?
I was pretty happy after Peak Velocity did mine, hope you see similar results.