Bicycle Mechanics - bottom bracket help (fsa gossamer / square taper etc)

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zachismisitok
10-21-10, 11:27 AM
I have a (or so I think) 2006 Felt f75. I've recently had some bottom bracket issues, so I decided to replace it myself.

I bought crank puller, bottom bracket socket deal, etc

Anyways, got the bottom bracket off, and I have unsuccessfully put on the wrong size BB twice no, so I am abs. confused about what size I need.

What I know:
- 2006 Felt f75.
-Takes a 68 mm BB
- It has a square taper FSA gossamer Crankset. (Yes, I know what bikepedia says, and it is incorrect)
- Crankset is a double
- The bottom bracket I pulled out is an RPM/Sugino bb-7240.
- I believe it's a JIS taper.

What size spindle do I need to buy?

I have tried 113mm, and it seems like the crankset is sitting too far out (I can't get the front der. adjusted to where it will shift into the top gear)

Ideas?

I appreciate any help- I promise I searched around all over. I think I need a 103 bb, but I really don't know and would appreciate a tad bit of help.


bikeman715
10-21-10, 03:10 PM
make sure the taper is right. have you try a 111 mm BB ?

desertdork
10-21-10, 03:47 PM
Apparently Sugino didn't imprint the spindle length on your old BB. You can measure the old spindle. If you doubt the measurement, you could contact FSA for an answer. FSA's site shows all their current road cranks use external BBs or BB30, so no tech info for the earlier square taper cranks.

Edit: When you do install, make sure to tighten to the correct torque. Insufficient torque won't necessarily push the crank onto the spindle, resulting in greater distance from the seat tube to the outer ring (and other problems).


badamsjr
10-21-10, 07:40 PM
Depending on how deeply you want to get into it, there are different square taper bottom brackets available. I have a Race Face that is adjustable for chain line, and I believe there are different length spindles available also. Of course, Phil Wood is the 'gold standard' for this type of BB.:thumb:

ultraman6970
10-22-10, 08:12 AM
Get a metric measuring tape and measure the axle as simple as that.

zachismisitok
10-22-10, 09:25 AM
Thanks for the replies everyone. LBS measured it to be a 103mm last night!!! I was surprised, but it explains why the crank was sitting so far out. Ended up rebuilding the old bb with new bearings. Smooth as butter now.

badamsjr
10-22-10, 09:39 AM
Campagnolo has a 102mm cartridge bearing BB--either Chorus or Record, that I use with great results.