Re: 7-speed cassette

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Subject: Re: 7-speed cassette
Posted by: Robert on December 12, 1999 at 01:51:55:
In Reply to: 7-speed cassette posted by Eric J. on December 11, 1999 at 20:55:10:

Message:
>Hi,
>I recently purchased a set of used MTB wheels for a song. The intended purpose was to have a set of back-ups and put a slick on the rear one for the indoor trainer. The rear appears to be true and in good shape with one exception; the #6 cog is loose! #'s 1-5 are pinned together and of course #7 is against the lock ring. I have disassembled this thing and can find no reason for this loose-ness. There is a spacer between the #6 and #5 cogs but it seems to be in good shape. The hub is an LX and the cogset is Hyperglide C. Anyone have any thoughts?
>Thanks in advance.
Is it a 7 speed or 8 speed cluster? The difference between 7 and 8 speed cog spacing is real small, but enough that if you space the cogs for a 7 speed with 8 speed spacers, there is a little play. You might need to either change the spacers or add one to take up the dead space.
If you tried to put in a regular cog spacer to take up the dead space, there might not be enough threads left on the lock ring. You can add a bottom bracket/freewheel spacer to take up the dead space.
You might need to take the cassette apart and use 7 speed spacers. If you have a 7 speed set that works fine, and you can get a spacer out. Take the spacer and see if you can put it between the cogs of the wheel you bought. If it fit's tight it has the right spacers, if it won't go it's got 8 speed spacers. If they are 8 speed spacers you can drill out the rivets holding the cassette together and rebuild it with 7 speed spacers, they should be real cheap at a good bike shop.
If, however, you find the cassette is a 7 speed cluster with the proper 7 speed spacers, then your problem is the hub is an 8 speed hub. Putting bottom bracket/freewheel spacers on it will fix the problem. Place the spacers on first and then put on the cassette. Wheels Manufacturing makes a special spacer just for using a 7 speed cassette on an 8 speed hub. A bike shop should be able to get you one of those special spacers, but they probably have the bottom bracket/freewheel spacers in stock. If this is your problem you will need enough spacers to give you 4.5mm of total spacing. A 2mm and two 1.5mm spacers would probably do it.

Post a Follow Up To This Message

Follow Up Message:

>>Hi,

>>I recently purchased a set of used MTB wheels for a song. The intended purpose was to have a set of back-ups and put a slick on the rear one for the indoor trainer. The rear appears to be true and in good shape with one exception; the #6 cog is loose! #'s 1-5 are pinned together and of course #7 is against the lock ring. I have disassembled this thing and can find no reason for this loose-ness. There is a spacer between the #6 and #5 cogs but it seems to be in good shape. The hub is an LX and the cogset is Hyperglide C. Anyone have any thoughts?

>>Thanks in advance.

>Is it a 7 speed or 8 speed cluster? The difference between 7 and 8 speed cog spacing is real small, but enough that if you space the cogs for a 7 speed with 8 speed spacers, there is a little play. You might need to either change the spacers or add one to take up the dead space.

>If you tried to put in a regular cog spacer to take up the dead space, there might not be enough threads left on the lock ring. You can add a bottom bracket/freewheel spacer to take up the dead space.

>You might need to take the cassette apart and use 7 speed spacers. If you have a 7 speed set that works fine, and you can get a spacer out. Take the spacer and see if you can put it between the cogs of the wheel you bought. If it fit's tight it has the right spacers, if it won't go it's got 8 speed spacers. If they are 8 speed spacers you can drill out the rivets holding the cassette together and rebuild it with 7 speed spacers, they should be real cheap at a good bike shop.

>If, however, you find the cassette is a 7 speed cluster with the proper 7 speed spacers, then your problem is the hub is an 8 speed hub. Putting bottom bracket/freewheel spacers on it will fix the problem. Place the spacers on first and then put on the cassette. Wheels Manufacturing makes a special spacer just for using a 7 speed cassette on an 8 speed hub. A bike shop should be able to get you one of those special spacers, but they probably have the bottom bracket/freewheel spacers in stock. If this is your problem you will need enough spacers to give you 4.5mm of total spacing. A 2mm and two 1.5mm spacers would probably do it.

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