I need to replace my Bottom Bracket since there is quite a lot of play. I bought this bike second hand and I thought the easiest solution was to just order the same part and replace it. But on closer inspection it looks like the drive side (photos 1&2) are a Shimano part while the nondrive side (photo 3) looks like a different part. Definitely doesn't look like SM-BB5700 on the nondrive side.
I'm quite new to this and bottom brackets seem like an endless rabbit hole. From my research I think I need a BSA bottom bracket but is the Apex 11 speed that I have compatible with the Shimano BB's? From what I've been reading it doesn't look like it is compatible with GXP? But this one was working fine, don't I Have GXP?
It would be nice if I could order one bottom bracket tool to take off this one and put on the new one. A good quality BB would be nice as well, I am open to any suggestions and need some help, thanks in advance!
by spartan_smyfox
2 Comments
Get a bsa gxp bottom bracket. Shimano axle’s are 24mm both side, the gxp is 24mm drive, 22mm non drive. My best guess is the person before bought a Shimano and realised it wouldn’t fit so put the other side back in, or is just using the wrong size. Either way, the BSA GXP is what you need!
Am I seeing this correctly? Is that a Shimano bottom bracket on a SRAM crankset? If I’m not mistaken, those should not work correctly at all. A SRAM crankset has a 24mm spindle on the right side that steps down to 22mm on the left side, and bearings in corresponding dimensions. Shimano uses a 24mm bearing on both sides, so I would expect it to have so much play as to be unrideable.
If the bike has been ridden like that for a while, that means all of the force has been applied through only one of the bearings. The left side of the crank arm has been spinning in there completely unsupported. There’s a good chance that the crankset itself is damaged. At the very least, you need to replace that bottom bracket with the appropriate SRAM version, but you need to make sure that crank set is safe, and isn’t going to break on you.
If the previous owner worked on their own bike, they probably did some similarly sketchy bodges. I highly recommend you have a knowledgeable mechanic look over that whole bike to make sure it is safe.
Edit: closer inspection reveals that there’s a SRAM cup and bearing on the left side and a Shimano cup and bearing on the right. In theory that would work but I’m really sketched out as to what the original owner did to get there.