Help required; FSA ISIS Bottom Bracket Q

[Bigbananabike]

I've got a couple of Truvative / Bontrager cranksets (doubles) that I need BBs for.
They're ISIS.
A guy on an auction here has 2 ISIS BBs. He's measured the length of the axle at 113mm.
He says thats for a triple.
Is that correct? How would that length axle go for a double? Would it really be too long?
Cheers

 

[gclark8]

ISIS BBs are readily available in 108, 113, 118mm and sell for about $45. Don't get caught in an auction, measure twice, buy once.

 

[oldbobcat]

He's measured the length of the axle at 113mm.
He says thats for a triple.

He's right. The 108 is for a double. If you try to use the 113, it will likely stick the outer chainring too far out for a double-ring derailleur to reach.

 

[Bigbananabike]

Dang!
I did have the thought that they should be about 109.5mm like Shimano Double.
FSA ISIS BBs are not as cheap as $45 here in NZ so I'll have to keep looking...

 

[gclark8]

Dang!
I did have the thought that they should be about 109.5mm like Shimano Double.
FSA ISIS BBs are not as cheap as $45 here in NZ so I'll have to keep looking...

Ask at Torpedo7, we use the same supplier.

 

[alfeng]

He's right. The 108 is for a double. If you try to use the 113, it will likely stick the outer chainring too far out for a double-ring derailleur to reach.

The 108mm ISIS BB may be the preferred bottom bracket for an ISIS double ROAD crankset, but you CAN use a 113mm ISIS with a double-or-triple ROAD crankset (if the frame allows)... the outer chainring will ONLY be 2.5mm further outboard ...

So, if Q-factor isn't critical (it apparently isn't to me!), then go ahead and get the BBs.

If Q-factor is critical, then adjust the cleats on your shoes.