frame question

[nytrose]

what is the easiest way to check if the subframe is bent? Can I make a few measurements easily? One ski looks a little forward than the other.

 

[grizztracks]

first, all a-arm bushings and ball joints need to be good. I had the bushings and lower ball joints replaced under warranty last summer. about two weeks into this season I noticed one shock running more to the rear of the upper arm than the other. It's hard to get a good measurement but I just stuck a finger in between the shock and a-arm. The biggest thing that told me something was wrong is when it started pulling to the left and I had to readjust the tow and handle bar alignment. The sled was out of warranty but yamaha replaced the subframe for free. One thing I noticed with the updated 09 frame is that the shocks (fox floats) seem to run more to the rear of the a-arm than with the 08 frame. I believe the 08 frame centered the shocks when new. anyone notice this?

 

[nytrose]

where was your subframe bent? My shocks look pretty centered in the a-arms. I took all the panels off including the front subframe panel and everything appears ok. Im just wondering if there is a quick measurement I can take to see if anything is tweeked.

 

[theCATman]

The shocks are NOT supposed to be exactly centered. They are supposed to be more towards the rear of the upper arm.

I don't know the measurements, but not centered is normal. And, like grizz said.... the arm bushings & lower balljoints need to be tight to get precise measurements. I have 1,300 EASY miles on my '08 and the bushings & lower joints are getting sloppy.

 

[nytrose]

I've got 400 kms on her shes pretty tight. Is there any measurements I can take say from the rear suspesion to the front suspension,or is it the shocks that pretty much tell the story.

 

[theCATman]

Look at the spindle angle too. If one is more vertical than the other, that will confirm something is wack.

FLOATS will look to be roughly 2/3 toward the rear arm, this is normal.

 

[grizztracks]

I put the skis against the wall in the garage and measured back to the top of the spindle to see if it changed the caster (spindle angle front to back). Mine shown a slight difference (1/8 to 3/16) but i'm not convinced this was accurate. some are saying the three small holes in the bottom of the frame gusset are distorted or elongated. mine didn't. The updated frame is gusseted on the bottom between the a-arm and back were the sway arm connects to the frame so I would think it's bending in those areas. In my case the fact that I had to make adjustments to make it go straight was enough for my dealer and yamaha. there are posts with pictures of the 08 vs 09 subframe.

 

[arteeex]

I hit a large root that was poking out of a terraced section on a trail. I hit the root with the right ski bolt while turning hard left and going no more than 10 MPH in 18-inches of fluff. After the impact it was obvious the spindle was jacked and the skis were misaligned. An indication that I also bent the sub-frame was a slight twist in the front bumper relative to the body panels. When I pulled the body panels off the bend in the sub-frame was subtle but noticeable in the way the frame members were no longer symmetric.

Before you start tearing down the sled, you might lift and support the front end and check that the shocks, a-arms, and ball joints are all tight and the handle bars are square. The shocks may not be centered on the a-arms, but they should have very close to the same spacing relative to the upper a-arms on both sides of the sled. If this is all good then try taking measurements from the rear suspension mounting bolts on the tunnel to points on the upper and lower a-arms. I don’t think a difference of 3 or 4 mm from side-to-side would be anything to worry about with this method, but if it’s greater and you don’t have any impact damage, load it up and take it to your dealer. Make some noise and see if you can get warranty coverage.

If you’re feeling ambitious, pull the body panels off and with the sled on the floor and level step back to look at the frame. My frame was seriously twisted but it wasn’t obvious while still on the sled. It was like Escher drawing where I had to look at it from several angles before I could see the problem.

You might also want to loosen and re-torque the fasteners at the major joints to confirm that something isn’t just loose and out of place.

 

[nytrose]

thanks gentlemen !

 

[scott32]

My eyes may be no better on Sunday as they are on Tuesday. Does anybody know how to use a square and measuring tape? Where are you nytrose? I'm in Huron County and I can help if needed.

 

[nytrose]

haha maybe over the summer?? im in hamilton

 

[scott32]

Run a long staight bar along side your track running up past the skiis, then make a mark on the straight edge approx. 6 inches back from center of your spindles. Then using a drywall square from this mark with the 48 inche end lapped over the ski, measure the distance to your center of the ski bolt. Repeat this using the same mark from your straight edge for the other side and the difference in the two will let you know if one side is bent and not the other. I hope this will help. While your at it you can also check your toe- out by measuring from center of one ski to next from back and front with the front measurement being 1/8 to 1/4 longer than the rear. This is with your handle bars perfectly straight. Hook tape on rear of tunnel to your handle bar hook center on each side with same measurements. Adjust your steering left or right untill it is so. Once again I hope you find this useful. I'd come down to Hamilton to help if it wasn't 2hrs away. I'm sure you can handle it. I've never tried this but a flex tape hooked on rear of the tunnel to your top dead centerof spindle would most likely tell the tale too. Let me know if you've resolved this.