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BROOKLINEBIKER 02-24-14 08:51 PM

Where to install a spacer?
Hi everyone,
I am a novice at bicycle maintenance and seeking some advice from the forum. I own a 2004 K2 Zed Sport, which is my winter/ city/ beater bike. I am looking to install a Shimano CS-HG50 free hub on a 26 X 1.5 wheel, along with a 7 speed 12-28T cassette. My local bike shop gave me a spacer to install without guidance on how to install it. Sheldon Brown has a write up explaining the need for a spacer but does not explain how to install the spacer that I could see. Youtube does not show how to install this (that I could see).How exactly is the spacer to be placed? Where does it go relative to the hub and the cassette?

hueyhoolihan 02-24-14 09:06 PM

i believe the CS-HG50 is a cassette not a freehub. soooo.... i think you may mean you are installing a CS-HG50 Cassette on your rear Shimano hub. if so, and i'm sure i'll be corrected if i am in the least bit wrong about this :lol:, any spacer should go on before the cassette. so it's spacer, cassette, lockring. i think:).

i'm not trying to be pendantic, it's just that you COULD be attempting to install a new freehub on your rear wheel hub shell, and that would be different. good luck.

BTW, if you can't start the lockring with the spacer installed, just leave it off. and then, if the lockring bottoms out before the cassette is tight, in addition to being a very unlucky person, you probably need a thinner spacer. ;)

HillRider 02-24-14 09:18 PM

Yes, the usual order is to install the 4.5 mm spacer, the cassette and then the lockring. The only problem can be if the cassette had long bolts or rivets that protrude past the largest cog and keep the cassette from sitting flush on the spacer and prevent the lockring from threading on. So, you can remove the rivets/bolts first and install the spacer behind it or install the spacer after the cassette and then add the lockring outside of it. Any small cog 12T or larger will clear the spacer.

FBinNY 02-24-14 09:29 PM

Whether and how to use a spacer is answered when you consider Why to use a spacer.

The cassette must overhang the outside of the freehub body so that the lockring bottoms against the cassette tightening it before it bottoms on the face of the freehub body.

So If the cassette isn't 1mm or so wider than the space allowed on the freehub body, an fails to overhang, you add spacers behind it to bring it out until it does. How much? enough to get the front of the cassette out beyond the freehub.

BROOKLINEBIKER 02-26-14 06:19 PM

Hi FBinNY, Hillrider, & hueyhoolihan,
Thanks very much for your detailed responses. I will be installing the spacer shortly (fingers crossed….)

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