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Frame Alignment Checking

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AshimotoK0:
Anyone reading my CB250RSA project resto will see that the bike has one fork stanchion quite badly distorted. I need to quiz the PO in the pub I go to to ask about the history but whatever, I need to check the frame alignment. MCID on here had put me onto an old school bike shop that does realignment but I would like to do some initial checks myself. I was thinking of clamping the frame to a solid bed with a long precision bar mounted through the swinging arm mount tube ( or a bar with cones on it) and adjust the frame position until it is clamped with the bar dead horizontal. (I have a digital inclinometer with dual lasers & accurate to 0.1 degree to set this up). Then mount another bar  with suitable adapters in the headstock tube and check that the bar is at 90 degrees to the horizontal bar in the swinging arm tube. If this measurement is out then worth the 200 mile trip to get it checked out/ realigned. Also been offered another frame with V5 but who is to know if it too is bent? Anyone on here done any DIY frame alignment measurements or can offer any further advice?
The PO (owned from new) did have a donor bike so there is a chance he swapped the stanchions from the donor. I think I will assume that the bottom yoke/ head bearings may be suspect, so I will replace.

sye:
How about the straight edge method on the rear wheel? If that's not right then chances are the frame is twisted.

Lobo:
Intriguing Ash, will be interested to know your findings; wondering what Hondas jig tolerances would have been back in the early 80s?

Your post does not mention verifying the castor angle in spec; nor checking any lateral offset of the headstock tube - both possibly affected by a front end collision?

Edit - I’ve now seen your post elsewhere wrt this checking, and suspect you’re well ahead of my observations! Forgive me.

taysidedragon:
Ash, when checking the frame you might as well check the rear swingarm for alignment as well.

AshimotoK0:
Sye ..  bike is totally stripped otherwise I would have tried the twin-string method 1st. Will also check out swinging arm of course. Wheels not a problem as got replacements anyway.

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