skydive69

I am having a bike built by Guru, and I wanted FSA carbon cranks, but they tell me they are on back order until June. On eBay, I see a set of carbon cranks, and they are Octalink. I must profess my ignorance in that another one that was up for bid gave the bidder the choice of Octalink or ISSIS BB. Is it simply a differenct kind of bottom bracket with the actual crank being the same? Thanks for the info.

Maelstrom 

The bottom bracket/crank arm interface (where they are bolted together) are different. You would need an octalink bb matched to octalink cranks for example.

BostonFixed

Octalink has 8 splines, where ISIS has 10 splines, (I think).

skydive69

You wouldn't happen to know if an FSA Megaexo intergrated BB is compatable with an Octalink crank would you? My bike is coming with that BB, and I have bid on this crank, and now am wonderfing if it will be compatable with my BB.


https://cgi.ebay.com/ws/eBayISAPI.dll...MakeTrack=true

Maelstrom 

Doubt it. FSA makes isis bb's.

BTW...SAWEET BB

skydive69

Uh oh, I might have screwed up bidding for that set of cranks.

skunkty14

Octalink is Shimano's version of a splined crank to BB interface. Per usual, Shimano decided it best to not use the ISIS standard that several manufacturers have agreed to use and share freely, instead creating their own design, requiring users to stick with Octalink products. So the parts are not interchangable.

Good luck with your build, can always sell the cranks off if you end winning the auction I guess.

phantomcow2

Ide keep the cranks if you win them, they are quite nice

skydive69

They sure look nice, and it would probably be easier to simply but a compatable BB on the machine and keep those wonderful carbon cranks!

phantomcow2

I agree entirely.

Grasschopper

Err FSA Mega-EXO is one of the new integrated BB cranks. IE the BB Spindle is part of the right side crank arm. The bearings are external like the DA or new Ultegra. So the answer is you can't use any other crank with your BB because it is part of the crank. Now which Mega-EXO is it coming with?

Here is the FSA product line, notice there are 4 doubles (2 of which are carbon), 2 compact and one triple in the Mega-EXO style.

This is not to say you can't use the crank you bid on on eBay but you will have to get a new BB as well which means you can bid on either the ISIS or Octalink as you then just buy the proper BB to go with what you win. FSA has stopped making Octalink cranks as they don't sell an Octalink BB and only want to support what they sell, the Octalink version you are looking at is NOS. FWIW the Mega-EXO threads into the same BB as an ISIS or Octalink so there wont be a compatibility issue there.

skydive69

The crank that comes with the bike is the FSA Gosamer (sp?).

Grasschopper

Right Gossamer Mega-EXO is one of the options from FSA. They come in double, compact and triple and have the integrated BB and use the oversize outboard bearings. Is it a compact? If so do you want to sell it to offset the funds for the carbon setup?

skydive69

I decided to cancel my bid on eBay, because I was venturing into country that I was not familiar with. I am still in the process of making final decisions as to how the bike will come equipped. One delightful thing it is coming with is a set of beautiful Zipp 999's!