Chainset frame clearance

RobWJL

Old School Hero
Spent a day building the bike today and seemed to be making good progress - headset installed, BB installed, etc. Homemade headset press worked a treat.

Was just about to call it a day and I thought I'd try mounting the crankset. It soon became obvious that the inner chainring was going to clash with the frame - frustrating as I'd purchased that BB (pictured) specifically with advice from the vendor that it would work with the Gran Sport double chain set.

Not sure where I go from here - change the chainset to suit the BB or change the BB to suit the Gran Sport chain set. What would be the most painless route? I presume buying a BB with a longer axle might be straightforward. The one I have is 116mm. what will I need to guarantee the chainring clears the frame?
 

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if its just a smidgen to close, you could put a washer behind the fixed cup. Its the same washer that people used to put on hubs prior to putting on the freewheel. An old skool LBS might have one. Otherwise, longer axle I'm afraid
 
Thanks both. The axle is symmetrical. I have seen a 125mm axle - may just try that but seems like a shot in the dark.

It is way too close at the moment so I don't think a spacer will do it.
 
pigman":2x4pnl50 said:
if its just a smidgen to close, you could put a washer behind the fixed cup. Its the same washer that people used to put on hubs prior to putting on the freewheel. An old skool LBS might have one. Otherwise, longer axle I'm afraid

Sturmey Archer made them, IIRC. I bought a couple from Cyclopedia in Watford about 8 years ago; if the OP needs one I may still have at least one of 'em in my spares box that I could post out.

David
 
Axle shouldn't be symmetrical IIRC, I should have an old assymetric 113mm campag lying around somewhere that you could try. Is there something stamped on your axle?

Shaun
 
70-ss is an Italian road axle. being symetrical (and not a track axle) I would expect that it's later than the GS cranks you have. What's the name of the frame again?

Shaun
 
I assume it's an Italian frame as those BB Cups are marked as Italian Thread. I've done a quick measure of the image in a graphics package and it's definitely not symmetrical, as I would expect.

I'd check that the axle is in the right way round as previously suggested. Looking straight at the Campag Shield, the longer side (drive side) of the axle is to your left (the left side in the image), if that makes sense!

Steve.
 
Hi

This prompted me to check again. I did it just now with caplipers - it is 100% symmetrical. Perspective skews it in the image.

It projects by 19mm from the face of the cups when installed. Probably needs another 3-4 mmm to make absolutely sure..
 
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