I need to have a set of forks cut down about 2.5 - 3 inches. The top end configuration is a groove with keeper.
Can anyone advise who could cut these for me.
GT250/ GT380 Forks modification
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- Yeah Man, the Interstate
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- Location: Medina OH
No, I need the outer tubes shortened. The forks are GT250/380 and do need to be stiffer. Ideally, I would like to have 1/2" - 1" max travel beyond the compression of the forks from the weight of the bike. But the immediate challenge is to shorten them be cutting the top of the tube and re-machining the groove for the keeper.
I don't know if the spring needs to be cut or if I can just compress it which might help by giving a pre-load and higher initial spring force. That spring is awfully light compared to the GT550 forks on there now.
I don't know if the spring needs to be cut or if I can just compress it which might help by giving a pre-load and higher initial spring force. That spring is awfully light compared to the GT550 forks on there now.
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In general...
In general...
K2 = ( L1 / L2 ) * K1
Where:
K2 = spring constant of new spring
K1 = spring constant of old spring
L1 = free length of old spring
L2 = free length of new spring
K2 = ( L1 / L2 ) * K1
Where:
K2 = spring constant of new spring
K1 = spring constant of old spring
L1 = free length of old spring
L2 = free length of new spring
Kevin R. Walsh '75 Suzuki GT-250 Cafe Racer
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Kevin , if a local shop cannot help you contact Franks http://www.frankmain.qpg.com/
the older i get the faster i was
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Frank's can (and will) make anything you want, but any decent machine shop should be able to cut yours down. I have no idea which would be cheaper. Frank's usually charges about 200 bucks for a set of tubes.
And yes, if you shorten the springs, they will be much stiffer.
Lane
And yes, if you shorten the springs, they will be much stiffer.
Lane
If you stroke it more than twice; you're playing with it.
Too many bikes, too much time, ENOUGH SPACE, FINALLY! Never enough money.........
Too many bikes, too much time, ENOUGH SPACE, FINALLY! Never enough money.........