Hi,

I have 105 octalink crank on my bike, the bottom bracket has gone, im going to buy a new groupset when I can afford it. In the mean time I just want to put a cheap shimano bottom bracket on, can I use any octalink or do I have to use a 105 botton bracket?

Many thansk

match the spindle length and bb width/threading

Hi apart from that any octalink will be fine then?

How can I check spindle length with looking at the old spindle?

Thanks

Shimano ES25 is just about the only option now, remove the old BB, it will have the length printed on a silver sitcker on the center, or you can measure it with the crank removed

Can i confirm that octalkink is the same as splined?

Thanks for all your replies.

There were two Octalink patterns, V1 which was used on most road cranks and V2 for most MTB cranks. Your 105 requies the V1 version.

You could use any V1 model, 105, Ultegra or Dura Ace, but the 105 is the only one in current production. There are two lengths, 109.5 mm for double cranks and 118.5 mm for triples and Licktons in Chicago has both of them for about $50. Look here and scroll down to find the one you need: https://www.lickbike.com/searchsite.p...ottom+brackets

HillRider can i not use the suggested Shimano ES25?

As above with HillRider, fogot about the V1/V2 spec.

Can you take your BB out? if so, it will have the exact spec you need printed on it, if your bike had a FULL 105 groupset, it would have had a 105 (5500) BB as seen here https://techdocs.shimano.com/media/te...9830612167.pdf pull yours, and replace with a matching BB.

If you can't remove, take it to a bike shop, and get them to replace, they can worry about spec / sizing

Not with your 105 crank, the ES25 is a V2 style. As I mentioned above, road (V1) octalinks came in only two lengths, 109.5 mm for double cranks and 118.5 mm for triples. Get the one that matches your crank.

Many Thanks all

Quick ? I maybe looking a t new crank, whats the difference between 9sp and 10sp in crank terms, im running 8 speed?