Whats bent here?

chickenStripCharlie

Coast to Coast
Ok, so I have two sets of tubes. Can you tell straightness before disassembling down to bare stanchions?

I plan on taking apart and doing seals on only the set I choose to run.

I did not notice anything wrong with the lower triple when all was apart. I sat it on a flat surface and checked to make sure it was making contact and not had one side lifted. Is there a better way?

I'm going to take apart and replace with the 1999 tubes and recheck sometime next week.

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I guess I'll double check that the bearings were seated straight, but all my spacers were machined right and everything lines up on the axle without binding
 
Could just be the forks twisted in the triples.
Loosen the triples and stand with the tire between your knees and straighten it up.
 
All of the above. try twisting the wheel with the clamp bolts loosened and see if that helps. It looks like the left lower is bent.

Easy way to check: Remove wheel (with the front end supported of course) grab the fork lower and rotate it. You should be able to see if it's bent. It should just rotate but if it turns and the end moves in a circle, it's bent and must be replaced.
 
Thanks guys. I will report back when i'm back home and have time to fiddle with it.
I can't remember this being a problem when i had my 1999 tubes in the same clamps, so it very well could be the left lower bent inwards.

(excuse the goober bars. They are just temp until my risers arrive)

(fckn ebay hit&miss BS)
 
Yes they can. Triples are not nearly as stiff as we like to think and can be twisted.

Try a 3 foot (or so) length of say angle iron or square aluminum tube held BELOW the top triple and another one just above teh tire and sight across them. Any twist will be obvious.
 
Honestly, because of parallax in a lens, none of us keyboard jockeys are going to really be able to see what's going on when it comes to seeing alignment on a screen. LOL. That being said, pretty clear advice on what needs to be checked.
 
If the tubes are straight, the triples cant be out of line ... can they?

Triples get knocked out of line all the time. Wreck a couple dirtbikes and you'll find that you often have to straighten up the triples afterwards with no damage done.
 
If you can find a piece of glass that will fit you can place it on the tubes and sliders to check if they are in the same plane.
 
So I got around to looking at this more. Here is what I tried:

- I swapped the 2001 fork tubes with 1999 omes - No change.

- I swapped the tubes (left tube right) - no change.

- I dropped the tubes down so the top clamp wasnt holding them at all - no change.

- measured the distance between the clamps on both sides - an even 207mm on left and right

- using some aluminum tubing through the triples I measured the angle of both fork tubes - same at 26.5 degrees.

- measured the steering head angle - same at 26.5*

- setup the tubes in a vice, making sure they were level, and with a dial indicator measured the runout at the stanchions. They were all within 0.05mm.


So now I'm confused as hell. If the forks are bent, the indicator test would be picked that up.

If the lower triple was bent, the angle I measured would not have been consistent between the L and R sides.

If the top triple was bent, it would have been ruled out when I lowered the tubes below it.

The only thing I can try now is to get some 2 1/8" pipe (very close to 54mm) and put that in the lower triple and see what it looks like, because the fork tubes themselves are difficult to measure (no good flat spots on them). But I highly doubt I have bent tubes and straight stanchions.

My solution to lifting the front with the exhaust on.
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Measuring the angle of the triples and steering head
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Checking the stanchions runout
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I couldn't wait for proper round tubing so I used some 1.5" square which measures close to 54mm diagonally.

It also is off the same way as the forks. Right up, left down. So maybe my cheap protractor just can't measure the angle difference well, but it looks like my lower triple is bent.

I am so fed up with Ebay

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You're test isn't going to work only running them through the bottom tree.
 
You're test isn't going to work only running them through the bottom tree.

I think if you got full contact all around the pipe in the clamp it would be sufficient to show you where each side of the clamp is pointing to.

Clamping some plate flat on one side shows a gap on the left so, everything so far points to the lower triple being a little bent and needing the L side pulled up a touch and R side pushed down a touch. Will likely try that when I have my 2 1/8 pipes as no amount of adjusting seems to correct it.
 

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I think if you got full contact all around the pipe in the clamp it would be sufficient to show you where each side of the clamp is pointing to.

Clamping some plate flat on one side shows a gap on the left so, everything so far points to the lower triple being a little bent and needing the L side pulled up a touch and R side pushed down a touch. Will likely try that when I have my 2 1/8 pipes as no amount of adjusting seems to correct it.
Your triples have matching offset. If they're warped, the fork uppers shouldn't slide through both triples. It will want to bind. The top triple can actually pull the bottom back into alignment.
 
Your triples have matching offset. If they're warped, the fork uppers shouldn't slide through both triples. It will want to bind. The top triple can actually pull the bottom back into alignment.

Ok

Taking this advice and the advice from waaaay back about moving the wheel in the forks I put the bike on the ground with everything loose, made a few circles and jumped to cycle the suspension with only the top triple clamped and what do ya know ..... the wheel 99% self centered even though I was convinced the bottom triple seemed bent. Pretty clear it isnt now. Or if it is it's only a very small amount not worth worrying about for now. I tried that adjustment with my knees before but it just didnt work. I had to get it on the ground and cycle the suspension

So, thanks everyone for the education!!!!
(I am a n00b, but willing to learn)

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