New rear wheel conundrum

[chillyuk]

My Raleigh road bike wheel has a 7 speed screw-on freewheel, sitting in 130mm spacing dropouts. I could use a new wheel shortly and am wondering about fitting a later type wheel with a freehub(?) These are more plentiful and seem less expensive than the older type I have now. I don't want to go to a lot of expense, and would like to keep my existing shifters. I have come to the following conclusions, so am I correct so far:

I need to open the drop outs to 135mm from 130mm
7 speed cassettes are still available for a freehub.

My question is, is the above feasable, and would the indexing be compatible between a freewheel and a later cassette? Also, considering how many new wheels you buy in normal use is it even worth bothering and would I be just as well to stay as it is now?

 

[John the Monkey]

I don't think you need to change your frame's spacing (unless you want to run an MTB hub, for some reason, they're spaced at 135mm). Modern "road" freehubs have a 130mm spacing.

7 speed cassettes; http://www.dotbike.com/productsP2487.aspx (among others)

On Mrs Monkey's bike, I had to pop a spacer behind the cassette's largest cog for it to work (the hub was a Deore 9 speed, and 8/9 speed cassettes are slightly wider, evidently, than the old 7 speed cassette I put back on).

On your last questions, yes it can be done, the indexing should be ok (as long as you're sticking with the right manufacturer for the cassette & shifters) afaik. Is it worth bothering? I reckon so, cassettes are easier to change than freewheels, and the freehub system has a lot going for it generally (Sheldon Brown's site explains in more detail).

the exception, I guess, would be if you have a really nice rear hub, in which case, get a new rim on it & new freewheel & keep riding that way.

 

[TheDoctor]

It's a 3mm spacer you need - it goes on behind the cassette and they're a coupla pounds. Existing lever and rear mech should work fine - AFAICR 7 speed was all the same spacing.

 

[chillyuk]

Thanks for the advice. I didn't realise about the 130mm spacing, and it was a perfect piece of advice about the 3mm spacer. At least I know what to ask for at the LBS.