BSA Goldstar DBD34 fork tubes

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Aug 24, 2005
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Having begun the rebuild of a recently acquired BSA "Goldie'",,I have found that the fork tubes appear to be barrel shaped, 1.250" at each end and 1.375" toward the mid section. I was going to have the tubes ground and hard chromed, not sure if that is viable now. can anyone verify if the tubes should be this shape, or are they an oddball?. BSA A10 and A7 fork are similar I believe.
Thanks.
James
 
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Do you mean the lower fork legs? The tubes, or stanchions in British parlance, should have a replaceable bush attached. One of my chums has a Rocket Gold Star here in Hong Kong and recently found that his lower legs were worn barrel shaped down the bores. He rebored the fork legs and fabricated some oversize bushes.
 
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I am refering to the upper stanchions, the parts that slide in the bronze bushes.
Thanks.
James.
 
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James, It seems counterintuitive that the stanchions should be barrel shaped, especially since the middle part - where you might expect the most wear - seems to be thickest. It doesn't make sense that a stanchion that runs through a simple bush should be anything but parallel. It may just be a manufacturing glitch - if these have been rechromed and ground before, it may be that the machinist was careless, as in grinding a length of tube back and forth there is naturally more wear at the ends where the tool head spends more time, a good machinist will make allowances for this. At least you now have the chance to make them straight.
 
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The legs are turned with that taper to fit the lower triple tree at the pinch point. Some after market pieces are all 1.250 and have split ring shims provided to make the fit work at the lower triple. The taper is above the area were the the top bushing can travel.
 
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Thanks for the clarification Norbsa, Clearly I should refrain from talking through parted cheeks about things that I'm not really conversant with!
 
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Thanks for the clarification norbsa, and Dave, thanks for your interest. I will be looking for NOS parts, don't want ill fitting aftermarket stuff.
Thanks again.
James.
 
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