Bicycle Mechanics - One Piece Crank Cups

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SirMike1983

09-03-08, 09:48 AM

I've read some materials on servicing one piece cranks. I'm familiar with just about everything except for servicing the cups. Removal appears to be using a dowel and tapping on it with a hammer to loosen the old cups. How are the new cups put in, aside from that expensive Park press thing? Park tool site (of course) only alludes to using its own cup press to put them into the bottom bracket, but would it be possible to use, say, a small hammer and little block of wood in a manner similar to how you'd remove them with the dowel?

vivalavaca13

09-03-08, 10:08 AM

Both described methods work. The Park press is obviously easier and there is a smaller margin for error. With the wood, I used about a 5 inch piece of a 2x4 and a mallet. Just be sure to apply even pressure to all sides of the cup as it is pressed in. And be sure to start with a clean area inside of the bottom bracket area! Just be careful and use caution and you can avoid buying another expensive park tool! :)
Hope this helps!