pic: WCD

[Gray Adams]

Originally Posted by DampRobot

I take your point about the 973 blocks being easy to machine, but I just can't get around the fact that there are 3 pieces that need to be machined instead of 2. I guess my question comes down to this: why do the bearings need to be in one piece, and if they aren't, what happens? Joey's response seemed to be that although this can cause the wheel to be out of alignment, nothing terrible happens.

On the other hand, if two piece (rather than 3 pieces) are hard to keep aligned, and this misalignment will significantly impact performance, a 973 (or 254, for that matter) style bearing blocks are the best option. I just wasn't really aware that this could be a large problem, and want to make sure that we don't make any drivetrain decisions that we'll regret next year.

Sorry for hijacking the thread, I just want to learn a bit more about the ins and outs of WCD bearing blocks, like the ones featured in this design.

The advantage of pressing both bearings into the same bore is that they're definitely lined up straight. You don't need them to be perfectly in line, but then you're going to wear out your bearings much more quickly, you're going to sap efficiency, and if its bad enough, the whole thing will seize up. You'll be able to see and feel the improvement of having the bearings in the same bore, but if its just impossible for you to do it that way, it can still work, just not was well