I currently have a UDC 36" trainer with 40mm bearings. Can i swap all these parts onto a Quax profi frame? According to UDC website the spec of the profi is 42mm bearings.
Ideally you would need to get spacers for the bearings. This is because the bearing housing on the 42mm frame will not grip 40mm bearings properly causing premature failure as well as likely feeling horrible to ride with.
You can DIY a solution using 1mm thick metal. The common solution is to cut the shims out of a beer or soft drink can.
I’d likely use the pop can trick but UDC does sell the 40 to 42mm shims for £5.00
Jim
Bearings
Thats great thanks for answers