R90/6 Fork Alignment

[brettironbutt]

Hello! Looking for help aligning my front forks. I disassembled the front end and rebuilt the forks and few months back. After I reinstalled the front forks, I tested the range of motion of the fork lowers, confirmed I did not have any stiction, and made sure the axle was able to spin freely throughout the entire range of motion. I then torqued everything back to spec and filled the forks with oil and assumed everything was good. I reinstalled the front wheel to provide added stability while I moved on with the rebuild. When I attempted to remove the front wheel to rebuild the hub and bearings, I encountered the front axle was “wedged” in to the for lowers and needed to tap the axle out with a mallet. I believe my forks come out of plane and/or parallel when there is pressure on the top plate and bolts when the fork springs are inserted- I have disassembled and reinstalled the forks multiple times and every time I begin to insert the top bolts with the springs installed, my axle will lock into the lowers. It will not spin and will not slide out without force. If the fork springs are not installed, the fork operation performs as expected. I have sequenced the tightening procedures but without success.

Any advice? Thanks!

[schrader7032]

Can you describe your method/steps for tightening all the fasteners?

[drpetemurray]

How do you stabilize the triple trees when torquing the Cap Nut and the Guide Support?

Do not rely on the steering stop. Do get a short length of black gas pipe and insert it into handlebar mounts. Use this in the center position to torque said parts.

[sherman980]

Sounds like the full extended length of your forks might be a tiny bit different between the two. A couple of mm's is enough to cause what you are describing. If that's the case, one axle hole is a bit "higher" than the other and you typically won't notice it when the springs aren't in place. You put the axle in and the "longer" lower fork leg simply rises a small bit to match the other as there is no significant resistance to the lower leg rising on the upper one. Once you put the springs in, the lower leg can't as easily "adjust" it's height.

First, make sure both upper legs are the same height above the lower triple tree and the top plate isn't slightly bent so one leg sits further down than the other. If they are the same height... and I've seen this twice over the years - first time drove me nuts trying to figure out what was wrong... Turned out in both cases the inner damper assemblies were machined slightly differently - probably from different parts batches - they're what determines where the fork "tops" out fully extended. In the end, it wasn't enough to cause any "alignment" issues that impact steering - the forks were not twisted and the lowers still move up and down smoothly on the uppers so I let it go. As long as the forks are aligned once you tighten the top nuts, you should be good. Best way I've found to check is with a glass plate pressed against the upper/inner tubes. If it sits flush on both sides, you're good.
Hope that helps.
Chuck S.

[r67boxer]

How do you stabilize the triple trees when torquing the Cap Nut and the Guide Support?

Do not rely on the steering stop. Do get a short length of black gas pipe and insert it into handlebar mounts. Use this in the center position to torque said parts.

I've used the following clip on Brook's Airhead Garage. He talks about not using the steering stop too.

https://www.youtube.com/watch?v=Oyhg1wYLcG8

Kevin

[drpetemurray]

How do you stabilize the triple trees when torquing the Cap Nut and the Guide Support?

Do not rely on the steering stop. Do get a short length of black gas pipe and insert it into handlebar mounts. Use this in the center position to torque said parts.

I've used the following clip on Brook's Airhead Garage. He talks about not using the steering stop too.

https://www.youtube.com/watch?v=Oyhg1wYLcG8

Kevin

+1
Brook does a fine job perhaps overkill with these very flexible front ends. Although I recall in his /5 video washers were placed to shim the top of the triple tree in order to obtain alignment. Not a fan of that remedy. The glass plate method works well for me.

[brettironbutt]

Thanks everyone! I used the YouTube video and now have a front axel that does not bind! Many thanks!
Brett