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Can I get away with a 118 instead of 113.

510 Views 3 Replies 4 Participants Last post by  LyNx
I've got plans this weekend and need to get a BB on order.
I'm using an internal, 68-113 now , but the only thing the place I need to order it from has in stock is a 68-118.
5mm's, that less than a 1/4". Other than adjusting the front d some are there other problems I would run into that I'm not thinking about?

Thanks all.
BTW, its a trutative Isis sline.
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Sometimes when the BB is too long, gear combinations like middle front, biggest cog rear will not work, as the chain will be on too much of an angle, and will continually try to fall off the biggest cog onto the next smaller one. Will this 5mm change be enough to make that happen? Maybe not, but you won't know until you try.
Cranks that use either 113 or 118 internal BB's (Isis and Octalink) are 47.5mm chainline and 50mm chainline. Using a 118mm should work fine as 50mm is now the norm...though I did have issues with a X.7 front derailleur and a 50mm chainline, replaced with a Deore and it works fine.
You can do it, but as RKJ said, it could cause some gear combos to not work as well as before because on the added angle. It's only 2.5mm a side, but you might be amazed at how much difference 2.5mm can make. Do they not have a 115mm width? Would be a compromise betwen the two.
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