TruVativ Crank/BB
04-16-24, 02:27 PM
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TruVativ Crank/BB
So I have a TruVativ GXP crank in a 68mm bottom bracket. Can I screw in the GXP Italian BB into a 70mm shell and use the same crank?
TIA
Charlie
TIA
Charlie
04-17-24, 12:45 AM
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The issue is the length of the spindle. If it was always offered in 68 & 70mm versions, there was probably a way to factor the 2mm. Most likely a spacer, not used with 70mm. Or possibly both BBs have the same outside width, with the difference made up internally.
So, your bike will answer for you. Is there a spacer you can leave off? Or measure both BBs and compare.
Of course there's the bad for you possibility that they made two versions of the crank itself.
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An ounce of diagnosis is worth a pound of cure.
Just because I'm tired of arguing, doesn't mean you're right.
“One accurate measurement is worth a thousand expert opinions” - Adm Grace Murray Hopper - USN
WARNING, I'm from New York. Thin skinned people should maintain safe distance.
04-17-24, 05:06 AM
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GXP cranksets index off the non drive bearing, by capturing the bearing between the crank arm and a step in the spindle. The drive side floats on the spindle and usually has plenty of room to spare before bottoming out on the drive side arm. The switch from 68mm to 70mm will not be an issue with a GXP crankset. Your chainline may change by 1mm, which is an insignificant amount.
04-17-24, 06:42 AM
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Yes, what dsaul said. English and Italian are built into the basic GXP design, and that design uses no spacers on threaded BBs.
04-17-24, 09:18 AM
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Many Thanks ! ! I really appreciate the info.
I presumed that was the case since I was unable to find any ref to an Italian GXP crank. Sometimes difficult to believe that designers/manufacturers can actually make some things easy.
Thanks again
Charlie
I presumed that was the case since I was unable to find any ref to an Italian GXP crank. Sometimes difficult to believe that designers/manufacturers can actually make some things easy.
Thanks again
Charlie
