CHECKING WHEEL AND FRAME ALIGNMENT


Another method to check wheel and frame alignment

From: John Bellis <bellis@space.net.au>
Date: Sat, 9 Oct 1999 01:57:56 +0800

Ever since I was sold an RG 500 with a handling problem, I have never solely relied on the stringline method of wheel alignment. It's possible to "wheel align" a badly bent bike and still have it self-steering dangerously either left or right.

My method will reveal to you a bent frame, (should it be bent) and will give heaps better alignment on a good frame than by the stringline method alone. Nearly all modern bikes have front and rear disks. First obtain a small 12 inch magnetic spirit level and put it on the rear brake disc. With the bike on a solid level floor, straighten the bike up so that the back wheel is exactly perpendicular according to the spirit level. Chock the bike up in this position so it doesn't move. Proceed to the front wheel, attach the spirit level to the disc there now and by gently turning the handlebars, position the front wheel so that it too is perfectly perpendicular according to the spirit level. Go back and forth rechecking to make sure both wheels are 100% perpendicular. You will notice the front wheel flops downwards to either side when you steer sideways and will (should) only be perpendicular when the handlebars point the bike straight ahead.

If you can immediately see the handlebars are off line, then the frame is bent. (I was horrified to see the 'bars on my RG 500 out of alignment by at least 25-30 degrees, when both wheels were perfectly perpendicular to the ground.)

Now use the stringline method to stringline/adjust the wheels into alignment when both wheels are perpendicular to the ground. If you can't do it (it will not align), then take your bike to a professional frame straightener and get it checked out and repaired. In my case the 3 month warranty had just expired on the bike and I foolishly kept riding it in its unsafe condition. A power slide through dust on the road triggered off a tankslapper which threw me into a signpost (4 broken ribs) and wrote off the bike. I was insured, so at least I got my money back. By the way, I take my spirit level with me when I go to view a used bike for sale, once bitten........

Hope this helps someone.

John Bellis


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