Old bb 116mm, can I use a new 115mm bb?

benws1

I am refurbing an old Slice MTB which is circa 2000. I have taken the old square taper bb out and it's a Eubico Sealed BB which states 116 on it. I'm guessing this is a 116mm bb. I also think the shell size is 68mm, but I will check that later.

I'm trying to find a new 116mm bb, but can only seem to find slightly different sizes such as 115mm and 118mm.

Is it ok to install a 115mm bb in place of the 116mm one? If I search for the exact make and model, I'm only finding other old bb's for sale in places like Ebay. Would like a brand new one if possible, not something that has been sat on a shelf for 20 years.

Thanks in advance.

whyamihere

As long as you have a few mm between the end of the crank arms and any point on the frame as they turn, you'll be fine. If you don't, a 116mm axle probably wasn't long enough anyway. The crank arms will each be moved in by 0.5mm, which you won't notice. If you have front shifting, it may need a tiny tweak, but will likely just work.

benws1

Thanks for that. The cranks have a bit of space so the half mm reduction either side will be fine.

I didnt realise that was the main consideration with sizes so thanks again.

I've subsequently found some unbranded bb's in the same size, but I'd rather go with a shimano replacement.

mully79

What type of cranks do you have ?
Old chainrings can be difficult to find if theyre worn so check you can find replacements before you commit to square taper. (especially stx rc)
Most of the modern replacement square taper cranks look awful.

JBA

If you have the budget have you considered swapping to a more modern bb and chainset?
A Shimano HTII bb and suitable chainset would be a bit more future proof.

benws1

Thanks. The cranks are some old Cyclone ct3 things. I thought about keeping square taper as the bike is going to be for my brother who will only use it infrequently with the family. It's not going to be covering huge mileage.

The thing only cost about £260 too years ago. If I can keep everything cheap and cheerful that would be great.

Saying that, I do like the look of hollowtech stuff. Dont know if I will get the bb shell faced though

I'm just working on the wheels today and its going to need a replacement rear. I also had to stand on the wrench to remove the freewheeel. It was pretty much welded on!