Author Topic: Bent Fork Tubes?  (Read 1227 times)

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Offline Copperman

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Bent Fork Tubes?
« on: June 20, 2013, 10:11:22 AM »
Hi All, im kind of stumped.  As you can see in the photo my left fork is about an inch higher than the right causing my wheel to be crooked.  What can cause this?  The forks seems straight when laying side by side and I can't find and evidence of anything else off.

Any suggestions?
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Offline 754

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Re: Bent Fork Tubes?
« Reply #1 on: June 20, 2013, 10:46:08 AM »
Turn them in the tree with the axle loose on one side, you will see if its bent . Or hold tube to tube ,turn one 90 degrees 4 times, and keep putting it against, the other to check for bend. Do it to both forks. There is a chance you have mismatched tubes..with no weight on them they should be same length. Or you could have. 2 different lower legs, late ones are longer.
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Offline iron_worker

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Re: Bent Fork Tubes?
« Reply #2 on: June 20, 2013, 11:04:04 AM »
Kinda looks bent to me...

IW

Offline Elan

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Re: Bent Fork Tubes?
« Reply #3 on: June 20, 2013, 11:24:35 AM »
also good to check alignment with a piece of glass, the right size to fit flat on the tubes, then see what corner(s) of the glass are lifting
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Offline strynboen

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Re: Bent Fork Tubes?
« Reply #4 on: June 20, 2013, 11:32:41 AM »
just roll them on a tabel....on the inner tubes...then its klearly to see..
if they not are pittet of rust they can be pressed back in a hydralik press..vith vooden blocks ,
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Offline 754

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Re: Bent Fork Tubes?
« Reply #5 on: June 20, 2013, 11:37:08 AM »
Dont use vooden or cast iron blocks.. Many, many accidents with them.use steel or alumnum blocks..
Maker of the WELDLESS 750 Frame Kit
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Kelowna B.C.       Canada

My next bike will be a ..ANFOB.....

It's All part of the ADVENTURE...

73 836cc.. Green, had it for 3 decades!!
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Offline strynboen

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Re: Bent Fork Tubes?
« Reply #6 on: June 20, 2013, 11:40:42 AM »
yes thats right. wooden blocks.they broke,,,fly aut.. and smash your face...yes aluminium or brass are best..and more stabil
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Offline Don R

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Re: Bent Fork Tubes?
« Reply #7 on: June 20, 2013, 11:42:36 AM »
Are they just twisted in the trees?
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Offline steam-powered man

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Re: Bent Fork Tubes?
« Reply #8 on: June 20, 2013, 01:11:23 PM »

i'd support the front end, and mount everything in place, with the wheel just touching the ground.  the triple mounting bolts should be snug enough to hold eveything in alignment, but loose enough for the tubes to twist in the triples. 

stand in front of the bike, hold the front wheel with your knees and twist the triples a bit.  you may find everything lines up much better, but check them with a piece of glass against the fork tubes, or other method.   
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Offline Dave Voss

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Re: Bent Fork Tubes?
« Reply #9 on: June 21, 2013, 07:38:37 AM »

i'd support the front end, and mount everything in place, with the wheel just touching the ground.  the triple mounting bolts should be snug enough to hold eveything in alignment, but loose enough for the tubes to twist in the triples. 

stand in front of the bike, hold the front wheel with your knees and twist the triples a bit.  you may find everything lines up much better, but check them with a piece of glass against the fork tubes, or other method.   

Also, try loosening the top nut on the triple clamp, it is possible that it has become rotated a bit in relation to the bottom, thereby causing the forks to swing a bit, disturbing the front axle alignment.
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Offline steam-powered man

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Re: Bent Fork Tubes?
« Reply #10 on: June 21, 2013, 08:41:53 AM »
YES!

(forgot about that part)
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Offline Copperman

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Re: Bent Fork Tubes?
« Reply #11 on: June 21, 2013, 09:57:12 AM »
Thanks for all the replies guys.  Dave Voss and Steam-powered man had it.  The tubes are straight.  Once I got it all cinched down I could tell that the top tree was a little off.  She's straight now.

I tore down the donor bike for this chopper build two years ago so some of this stuff is not fresh in my head anymore.   :(

Thanks for the help....I know I'll be back.  ;D
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