Beginner question on bearings?

I’m getting the Qu-Ax Splined hub with a Nimbus X 2007 CrMo 20-inch Long-neck Frame. So the frame says it has 40mm bearing houses, but the hub says the outer diameter of the bearing housing is 42mm. Does that mean that pair of frame and hub won’t work or do I have to buy something to make it work? Also has anyone ever used any of these two items, I’d like to hear your reviews please? Thanks, Joe.

The pair most likely wont work together, the bearing holders on the cromo frame are machined to fit 40mm bearings, other frames such as the Nimbus II have cheaper bearing holders which will fit both 40mm and 42mm.

There is actually a version of the frame you mentioned designed specifically for street riding which will indeed fit the 42mm bearings as well as a trials tire if you so wished: http://www.einradladen.net/shop/show_product.php/products_id/650 however it is not listed on UDC as a spare part so you may have to call and ask for it. I linked you to municycle.com because UDC US seems to be out of stock on the full uni.

there are few instances where they did not fit, when you order, tell them what you want to do and they will tell you something like

its not made for it, but the tolerances on the bearing caps are not that particular, don’t worry about it. it will fit.

Thats not the case, the cromo Nimbus X frame has machined bearing holders just like I said. It’s very doubtful that the frame will fit unless he goes with the street version I linked to. Frames such as the Nimbus II and the old Nimbus X longneck are the ones which are not particular and will fit either 40 or 42mm.

Listen to Brian O on this. If the bearing holders are machined, then they will only fit the size bearings that they were designed for. Your best bet, if you still have questions, is to talk to the people that you are buying these items from.