alignment gauge

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1608
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alignment gauge

Post by 1608 »

I'm sure this has been done before, just thought I'd share my idea of a wheel alignment gauge made today. Fed up with stretching a length of string and fiddling with a tape measure etc. Simply rest the plank on two axle stanmds or similar and ready to go. It came about after adjusting the rear chain and losing count of the number of flats on the adjuster screws.



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Rob Harknett
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Re: alignment gauge

Post by Rob Harknett »

AJS had a rear wheel alignment tool that would fit in a tool box. It is like a profile template of the rear wheel rim. There was a bracket on the lower frame rail to bolt the template on.
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alanjennings
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Re: alignment gauge

Post by alanjennings »

I use a 7 ft by 6 inch straight board with a cut away for the centre stand mounted on 2 4 inch square wooden blocks. I feel you are really pernickerty you need to adjust for the different diameters. of the front and rear tyre diameters. Easy peasy!!
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Rosy
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Re: alignment gauge

Post by Rosy »

Do you allow for the width of the tyre? a straight edge against a 3.50 rear will stand off a 3.25 front. When I used to do this I tacked on a strip of timber to make up the width difference, but I had 4.00r against a 3.25f.
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Re: alignment gauge

Post by alanjennings »

Yes, take half the difference of the width and do as you say!
Alan [Morini] Jennings
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Re: alignment gauge

Post by 1608 »

No, the legs are intended to touch on the wheel rims. Unlike when the tyre centres who use the tyre wall which never seems entirely accurate to me. But there you go. I haven't cut out for the centre stand as my set-up abuts the rims at appro mid way or axle height.
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Rosy
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Re: alignment gauge

Post by Rosy »

Iv'e been thinking about your gauge, with the QD rear wheel the brake hub/sprocket bolts up square to the swing arm fork, so when the wheel spindle is put through and tightened it has no alternative but to be square with the other side, so how can the wheel not run true to the front. If it is out then doesn't that mean that the rear wheel nuts/spacers etc are not sitting flat/square on the lugs. The adjusting nuts are just for chain tension yes/no. But I will add it could be my misunderstanding of the set up.
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clive
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Re: alignment gauge

Post by clive »

Rosy wrote:Iv'e been thinking about your gauge, with the QD rear wheel the brake hub/sprocket bolts up square to the swing arm fork, so when the wheel spindle is put through and tightened it has no alternative but to be square with the other side, so how can the wheel not run true to the front. If it is out then doesn't that mean that the rear wheel nuts/spacers etc are not sitting flat/square on the lugs. The adjusting nuts are just for chain tension yes/no. But I will add it could be my misunderstanding of the set up.
a couple of thou at the spindle is a lot more at the rim. It is certainly possible to have the adjusting nuts wrongly adjusted! The snailcam versions of the spindle adjustment have a factory set adjustment on one side to allow for inconsistencies in the mating of parts. If you change a rear swinging arm for one from another frame you have to readjust.
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Re: alignment gauge

Post by 1608 »

Well explained Clive.
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