Internal to external bb

nato

Hi everyone.

Been riding for ages but just jumped on the interweb band wagon and have a question that im hoping you can answer for me.

After a small health scare last week im more determaned to get out on my bike more now so im going to start upgrading.

First part im changing is the gears and drivechain and ive found that the new shimano slx crank is perfect for my needs.
trouble is its an external bb where as mine is currantly an internal square taper kind.

Question is are these a direct swap?

If anyone has done such a swap will i need anything else or is it straight forward.

Many thanks all.

Stu

verloren

I recently had a similar swap done. The key issue is that the external bottom bracket is pressed against the frame, and it's imperative that the two sides of the bb be parallel. That means that the two sides of the frame's bb opening (sorry, can't recall what the proper name is!) must be parallel. This is achieved by 'facing' each side with a special tool (basically scraping off any bumpy bits of metal until the sides match). It's possible to do this yourself, but given the cost of the tool I took it to my lbs and had them sort the whole thing.

nato

thanks for your advise, im popping into town in a bit so il see if its something the shop can do.
Thanks again

Speed_King

I had the same done on my rockhopper when i bought the new slx, my mechanic faced the ends up for me perfectly and fited the new BB snugly it is deff the way to go and it takes no time for them to do. just book it in and away you go