Back wheel adjustment

[W]

My back wheel on 24 speed race spins freely off the bike but when I put it on the bike and test the spin it seems to not spin so freely. It is not rubbing on the brakes etc. Any ideas if I still need an adjustment or is this normal? thanks

[DaveM]

Two things I can think of.
1. When it's on the bike, the chain is on which means your freehub/cassette is held still. There is always going to be some friction from the freehub as it ratchets. It shouldn't dramatically slow down your wheel, but it always will some. Try spinning your cassette off the bike. If that seems stiff, you might need to try to lube it.
2. On some quick release wheels, when you clamp them into the frame, the QR actually tightens up the bearing adjustment a little. Some people suggest adjusting your hub bearings so they have the tiniest amount of play when they're off the bike so the QR will tighten it up to a proper adjustment when it's on the bike. Won't hurt to try this. But be careful and check that the bearing play does go away when you clamp the wheel in the bike. You don't want to ride on it loose very much or you can damage the bearings.