BMX - Bottom Bracket Help

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View Full Version : Bottom Bracket Help


DarthCoCoaPuffs
05-29-06, 02:59 PM
I just got some new three piece cranks (Masera Protocol), and I'm upgrading fomr once piece, which means I don't have much experience. I think the type of bottom bracket I have is American. But my problem is that I can't fit the cup and bearing into the bracket. The y are too big to fit inside. I'm not sure what my problem would be, othen than the fact that I might have gotten the wrong size for my frame. Here's some pics of my BB. Does this look like an american sized BB to you? Also the diameter of hole where the cups go in my BB is about 54mm (a little more than 2in.)

http://us.a2.yahoofs.com/users/447b5c0fz71950eca/2cc9scd/__sr_/707escd.jpg?phoM2eEBpj2DpqsH

http://us.a2.yahoofs.com/users/447b5c0fz71950eca/2cc9scd/__sr_/88a8scd.jpg?phoM2eEBX9oF6EiU

http://us.a2.yahoofs.com/users/447b5c0fz71950eca/2cc9scd/__sr_/8b16scd.jpg?phoM2eEBDbUtBgUe

http://us.a2.yahoofs.com/users/447b5c0fz71950eca/2cc9scd/__sr_/3488scd.jpg?phoM2eEBnZtRXKxo


eightdip
05-29-06, 03:01 PM
what frame is that?

FuzzyRyder
05-29-06, 03:02 PM
Yes, it is an american bb. Your problem is that you havent taken out the bearing races from your old one piece cranks. You take a flat screw driver and a hammer and tap out the cups that are pushed into your bb. Now the bearings from your new cranks should press right in.


DarthCoCoaPuffs
05-29-06, 07:26 PM
Ahh ok. I wasn't sure if those were part of the bracket or not. I was too afraid to try to remove them because I didn't want to mess up my frame. Thanks a lot btw.