Hello
I have decided to rebuild the front wheel on my 1961 G12 CSR (re-chrome the original Dunlop rim, then get the drum trued and oversize linings turned down to suit) in order to try and get the best out of the brake. I was going to just get the drum trued/linings turned to see if it makes any differrence but I don't want to risk a rebuild at a later date pulling the drum out of round.
The bike is kept at my mums (a couple of hours away) and I have just brought the wheel back with me to do the work. I have made a note of the spoke pattern and after removing the tyre I measured the rim offset. With the brake plate off, the wheel parallel to the ground, drum side uppermost, with a straight edge across the drum face there is 3/8" between the under side of the straight edge and the rim (the edge of the hub on the drum side is 3/8" above the rim).
I should have checked that the wheel was central in the forks before I left but I didn't have time. I could rebuild it as it was and re-check between the forks before getting the wheel finally checked by a wheel builder, but that will mean another month before I can get the drum trued.
Does 3/8" sound correct?
Thanks
CAB
1961 G12 CSR Front Wheel Offset
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- dave16mct
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Re: 1961 G12 CSR Front Wheel Offset
All heavyweight AMC are supposed to have no offset. So if it's 3/8" on the other side you're OK. I made a Taverner jig as in the Vintage Motorcyclist's Workshop by Radco. I find it isn't too difficult and doesn't take much truing when removed from the jig.
Dave.
Dave.
- robcurrie
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Re: 1961 G12 CSR Front Wheel Offset
The spoke pattern works out by itself because of the straight spokes and the holes in the hub. As Dave says, there is no offset.
As a side note, the front and rear rims have opposite hole patterns, hence different part numbers.
Rob C
As a side note, the front and rear rims have opposite hole patterns, hence different part numbers.
Rob C
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Re: 1961 G12 CSR Front Wheel Offset
Thanks for the replies.
I will check for equal offset on the opposite side of the wheel before stripping it.
CAB
I will check for equal offset on the opposite side of the wheel before stripping it.
CAB
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Re: 1961 G12 CSR Front Wheel Offset
Before stripping the wheel this afternoon I measured the opposite side (cover plate side) at 5/16 compared to the 3/8 on the drum side.