68mm right/right on a 70mm right/right Shell?
08-13-23, 12:30 PM
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68mm right/right on a 70mm right/right Shell?
Hello im currently replacing my Botton bracket for a new one.
my old one Is italian style right/right 36 x 24tpi - 70 mm
I can only get right/right 36 x 24tpi - 68 mm
my question Is if i can use the 68mm in the 70mm Shell?
my old one Is italian style right/right 36 x 24tpi - 70 mm
I can only get right/right 36 x 24tpi - 68 mm
my question Is if i can use the 68mm in the 70mm Shell?
08-13-23, 02:29 PM
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Are you in Arkansas, US or Argentina? If the US, and if your LBS won't order the right part, I'd recommend Bike Tires Direct, Modern Bike, Velo-Orange, or even Amazon as a source.
If you're in Argentina, I can't help.
If you're in Argentina, I can't help.
08-13-23, 02:31 PM
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Im from argentina. I can only get 68mm, same thread.
08-14-23, 04:38 PM
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The Italian shell inner diameter is 1.375 in. ISO is 1.370. Your ISO BB will likely be a loose fit threadwise.
08-14-23, 05:11 PM
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...sometimes they work OK, if it's a sealed unit. But you need to be mindful about getting the correct spindle length, so your crank arms don't end up too close to the chainstays and interfere.
As a last resort, you can get someone with a BB facing tool to take off a mm on each side of the shell, making it a 68mm BB shell.
But Italian threaded bottom brackets have been sized to fit 70mm shells forever. So I have the feeling that there is something else going on here, of which I'm unaware.
AFAIK, I cannot buy an Italian threaded bottom bracket unit that will be sized for anything except a 70 mm shell. I've used one of those once in a 68mm shell that was rethreaded larger to Italian threading because of damage. It worked fine.
As a last resort, you can get someone with a BB facing tool to take off a mm on each side of the shell, making it a 68mm BB shell.
But Italian threaded bottom brackets have been sized to fit 70mm shells forever. So I have the feeling that there is something else going on here, of which I'm unaware.
AFAIK, I cannot buy an Italian threaded bottom bracket unit that will be sized for anything except a 70 mm shell. I've used one of those once in a 68mm shell that was rethreaded larger to Italian threading because of damage. It worked fine.
08-16-23, 11:10 AM
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My DS has been rethreaded for Italian threads due to cross-threading by the previous owner or his mechanic. When I wanted to install the TA Cyclotouriste BB, it was apparently cheaper and easier to by a French BB and axle, an English NDS cup, and an Italian DS cup. It's been working for 38-40 years ago.
So, for an Italian BB in Argentina, web order from Europa or USA?
So, for an Italian BB in Argentina, web order from Europa or USA?
