Bicycle Mechanics - Shimano M510 8/9 speed freehub on 7 speed?

I just picked up a wheel with a shimano FH-M510 freehub. Google has told me that this is a 8/9 speed freehub. Unfortunately I _don't_ want to upgrade my 7 speed shifter and derailleur. I have a nashbar 7 speed cassette which fits loosely (i.e. completely unusable).

What is the cheapest and easiest way for me to get this wheel working on my 7 speed bike?

just go to the shop and ask them for a spacer that converts your 8/9 t0 7

Go to your local LBS and get a spacer. That's what I did.

You type faster LOL!

There's another possible problem.

Measure the distance between your rear dropouts. If it's 130mm, that's good. A spacer for your freehub body, grind off the rivets from your cassette, and you're good-to-go.

If it's 126mm, the new hub is going to be a skosh too wide. Options are to spread your dropouts to acommodate the wider hub or to force fit the wider hub into your frame every time that you remove your rear wheel.

Measure the distance between your rear dropouts. If it's 130mm, that's good. A spacer for your freehub body, grind off the rivets from your cassette, and you're good-to-go.
You will have to grind off the rivets or unscrew the bolts that hold the cassette together to allow the cassette to clear the 4.5 mm spacer if it is installed behind the largest cog.

An alternative is to install the spacer between the smallest cog and the locknut and no modifications to the cassette are needed. I've done both and both work equally well.

An alternative is to install the spacer between the smallest cog and the locknut and no modifications to the cassette are needed. I've done both and both work equally well.

brilliant! i did this today, and it works great. don't know why i couldn't think of it myself, but thank you.

edit: found a caveat.

you need to have an 8+ speed RD in order for this to work. if you put the spacer on the inside, then you can use a 7 speed RD.

I want to go the other direction. I have a 7 speed hub body on the wheels for my RB1, and I want to go 9 speed. I think we may be able to just swap hub bodies. If you are interested, let me know.

Jared

I've been riding with 7-speed freewheels for a long time, and 8-speed Shimano shifters. I'm sure I had checked it out back at the time but I checked Sheldon's information recently and found that the cog spacing for 7-speed and 8-speed is not identical but very close. OTOH 9-speed spacing is different so to actually go 9-speed you would need different shift levers.

I've been riding with 7-speed freewheels for a long time, and 8-speed Shimano shifters. I'm sure I had checked it out back at the time but I checked Sheldon's information recently and found that the cog spacing for 7-speed and 8-speed is not identical but very close. OTOH 9-speed spacing is different so to actually go 9-speed you would need different shift levers.

5.0 mm on the 7 sp VS 4.8 mm on the 8 sp. You can get perfect shifting on 8 sp shifters with a 7 sp cassette by using the 8 sp spacers on the cassette instead of the 7 sp. That means using 4.8 mm spacers on a 7 sp

edit: found a caveat.

you need to have an 8+ speed RD in order for this to work. if you put the spacer on the inside, then you can use a 7 speed RD.
That's not correct.

First, there is no such thing as a 7 or 8-speed rear derailleur since the indexing is in the shifter.

Second, I did the 7-speed cassette on an 8-speed hub conversion for my old Trek 7000 MTB that came OEM 7-speed and the rear derailleur (Shimano LX) was a "7-speed" rear derailleur and I put the 4.5 mm spacer right under the lockring. All you have to do is properly adjust the limit screws.