BB Size for Specialized Bighit Dh?

lee96

Can anyone tell me what size BB i need for my Bighit. The crankset i'm running is a Hollowtech one, and the crank bolt for the left crank arm keeps repeatadly coming undone, I changed my mind about milling it up with loctite because my Bike sounds horendous. Time for a new BB i think.

Thanks

supersonic

What is your crankset exactly?

lee96

Shimano Hollowtech, to be fair it has no numbers on it because all of the paint has rubbed off on the outside arms and in turn my shoes went from purple and green to black and my crank from black to silver. I will check anyway.

nicklouse

look on the back. there is more than one hollowtech standard and hundreds of different cranks.

without the correct info you will have to dismantle it and see.

supersonic

WIthout knowing the exact chainset and year of bike is hard to say lol. There are more than one type of Hollowtech. Infact 3 axle standards!

lee96

It's an 02 or 03 bighit dh, with the 24" rear wheel.

supersonic

If the crank is falling off, you need a new crank.

lee96

My Bottom bracket is squeeking too though. I'll go and read the Crankset.

tom_howard

Clearly the ruler/vernier caliper/tape measure hasnt quite made it to Kingsbridge...

lee96

Haha, small town in the west country. Computers are a luxury apposed to carrier pigeons

lee96

Just went out the shed. nothing on the backs of the arms, just Shimano Deore, Hollowtech. I'll measure it all tomorrow night. Just figured someone might know on here. Probably would have helped if i could give a bit more information :roll:

supersonic

Is it an octalink bottom bracket? Just measure it when you remove.

nicklouse

yes there will be. there always is and always has been.

get a better torch. the make and model and length will be there. normally arrond the pedal hole and often on the arm as well.

lee96

It's a spline and not a sqaure taper. If that's what you mean by octalink.

nicklouse

Ah so HT1 could be any length still.

lee96

Do i need the axle length?

nicklouse

yes.

what size BB i need for my Bighit

unless you are not going to use any of the old parts?

the frame has a 73mm shell.

as can be found on Speshs webby.

lee96

Could you tell me how to measure it please?

Sorry for so many basic questions, Drivetrains just aren't my thing.

nicklouse

see edit above.

lee96

Sooo, I need a 73mm bottom bracket shell? and it will all be ok? worth getting new crank arms too? hopefully it is the BB that's sqeaking and not my suspension bearings? Already dreading the moment when i have to send my shock and forks to TF.

nicklouse

lee96 wrote:

Sooo, I need a 73mm bottom bracket shell? and it will all be ok? worth getting new crank arms too? hopefully it is the BB that's sqeaking and not my suspension bearings? Already dreading the moment when i have to send my shock and forks to TF.

FFS what do you want to do?

replace the BB? then you need to know what cranks you have!
Replace the Cranks? then you need to know what cranks you have!

or buy all new? just buy any that fit a 73mm BB. which is most now as they fit either 68 or 73mm

cooldad

May be easier to get a HTII - comes with ext BB so will fit any sized shell, rings and cranks, Deore costs somewhere around the £50 odd mark and much better than octolink. You should get the BB faced though.