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Discussion Starter #1
I had not ridden for a while as I had new knees installed (good job at UNM) so when I fired up and went down the road, I was looking for surprises. Fork oil coming out!! OK, need new seals. 28 K on the bike, a K2, so not unusual. Pulled the forks and put then in the vise and turned the tubes to see if straight. The right was 3/8 inch out of true and the left 1/4 inch. Not the original owner so not surprised. I had the forks off when working on the front of the bike before my new knees so I probably put them in with the bends not in line as before which would explain that new high speed wobble. We used the pipe bender to straighten out our dirt bike fork tubes all the time, but I am usually going twice as fast now. Just how much bend is safe if I get them lined up to reduce that wobble? Will the old pipe bender trick straighten them enough to be safe? Pick up some used ones? Any thoughts?
 

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That is quite a bend and I would have to guess that the bends are just below the lower triple clamp, in which case someone has rammed into the back of a stopped car or similar. Unless you are strapped for a buck I would replace them for the sake of my peace of mind.
 

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put them in the v-blocks and use the hydraulic press to straighten them. Install and ride straight. No worries as long as the upper and lower clamps are true. Not badly bent IMHO. Should be totally correctable. I've straightened much worse.
 

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on high performance street bikes...BTW. Much harder to do on the perverted forks more modern sport bikes are fitted with.
 

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Discussion Starter #5
OK, got them all apart and when rolled on a true surface it looks like the bends are a little under 1/4 inch on the right and little under 1/8 on the left. OEM is $342.00 US, each!! I am just going to mark the high spot on each and put it to the rear when reinstalling, that way I am all set up for the next bump. My neighbor said that is what he and his buddies did when racing dirt bikes because it is just too difficult to bend them re-straight when it is so little. Might even scratch or put a flat spot, too, which would screw up the seals.
Thanks.
 

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OK, got them all apart and when rolled on a true surface it looks like the bends are a little under 1/4 inch on the right and little under 1/8 on the left. OEM is $342.00 US, each!! I am just going to mark the high spot on each and put it to the rear when reinstalling, that way I am all set up for the next bump. My neighbor said that is what he and his buddies did when racing dirt bikes because it is just too difficult to bend them re-straight when it is so little. Might even scratch or put a flat spot, too, which would screw up the seals.
Thanks.
There will be places that can retrue forks.

Last time I had it done was near 25 years ago, but provided they don't have creases it works just fine.

Pete
 

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There will be places that can retrue forks.

Last time I had it done was near 25 years ago, but provided they don't have creases it works just fine.

Pete
There is a strong possibility that the tree/clamps have been warped and should definitely be checked too. If there is a crease in either leg, you can bet on it.

The forks can be straightened by a machine shop or anyone with a hydraulic press and v blocks as long as there is no crease. There is an animated gif on this page showing some of the straightening steps.

Motorcycle fork tube repair
 
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