Bottom Bracket Sizing

JoeKersh

Hi all!

i currently have this frame : http://www.evanscycles.com/products/spe ... e-ec001412

and i'd like to fit the truvativ blaze crankset to it, i have already purchased this.

i was also wrongly informed that a truvativ powerspline bb in 68 x 118 would fit.

wrong type of spindle, wrong length spindle.

i believe that i need an ISIS bb, this is fine. i can go out and buy one. but i dont know what size i need.

the bike originally had a 68 x 118 shimano bb with suntour cranks. but the 68 x 118 powerspline (despite being the wrong splines) wouldnt give me anywhere near enough clearance for the cranks on the chainstays. i would have had to severely space it out.

so does that mean i should be looking at a 68 x 127 truvativ ISIS bb or similar? or should 118 fit and im doing it wrong?

hlp would be appreciated, id run it into a local bike shop and save the hassle but its hard to get to tone for me so id rather try to sort it this way.

P.S. excuse me if i sound stupid, ive just started MTB coming from years of BMX (they are much simpler )

thanks!
Joe

nicklouse

how many splines?

IE is it ISIS? if it is then 113mm should do. it might need a 118mm axle but i would be very surprised.

http://www.bikeradar.com/forum/viewtopic.php?t=12737715

antfly

It says octalink 118 in the spec.

JoeKersh

yeah ISIS, but the powerspline 118 didnt fit? does that mean a powerspline 118 is different length to an ISIS 118??

nicklouse

they have nothing to do with each other.

blablablacksheep

i think what he means is this, correct me if wrong.

You trying to replace the BB for bike+crankset correct?

The bikes BB is either 73mm or 68mm, i believe yours probaly 68mm, so you need to remember this when installing the spaces for the BB.

The frame uses a octalink BB which means you need to either get another octalink BB to replace or if you buying a crankset make sure it is compatible with octalink BB.

If you trying to buy a new crankset with the current day external BB, then you need to have the frame faced i believe.

Basically you either buy a same style BB/crankset
Or
Buy a new crankset with the modern day external BB but means you gota do a lot more DIY+poss frame facing.

nicklouse

blablablacksheep wrote:

i think what he means is this, correct me if wrong.

You trying to replace the BB for bike+crankset correct?

The bikes BB is either 73mm or 68mm, i believe yours probaly 68mm, so you need to remember this when installing the spaces for the BB.

The frame uses a octalink BB which means you need to either get another octalink BB to replace or if you buying a crankset make sure it is compatible with octalink BB.

If you trying to buy a new crankset with the current day external BB, then you need to have the frame faced i believe.

Basically you either buy a same style BB/crankset
Or
Buy a new crankset with the modern day external BB but means you gota do a lot more DIY+poss frame facing.

there is so many errors in this i should just delete it.

the OP has had the answers given to them.

ISIS and 113mm axel.