Galaxy - replacing drivetrain, suggestions please?

[beanzontoast]

So, my old Galaxy, which I've had about 6 years and which is still running many original parts from 30-odd years ago, hasn't had anything spent on it in a major way since then, and I suspect if I was to have a new chain fitted (for example) the gears wouldn't like it - I'm guessing the components have all worn together and all need replacing together. I've noticed a bit of wear/play in the rear derialleur cogs too, so that will need replacing. Currently, it has a triple up front (48,38,28 I think: originally, it was a 52-something double). The gearing at the rear is a 6-speed block. The bottom bracket seems fine, by the way.

Can anyone suggest me a set of parts to self-fit? Something with a bit of durability would be welcome. My budget for the whole operation is between £50 and £150 - is this reasonable? - obviously the cheaper I can do it while not cutting on quality, the better.

I'm really looking for advice here as, though I've replaced individual parts in drivetrains before, I've never undertaken a complete refit of this type. Quite happy to do it myself (and save on labour charges, plus learning more as I go along) - it's the suggestions for decent kit that I need please.

 

[PpPete]

First - do you have old style screw-on freewheel or cassette type?
See here for the difference, although suspect the former if only a six speed block.

Next check your over lock-nut distance like this
My guess for a 30 y.o. Galaxy would be 126mm - which will just about take a modern 130 mm hub without resorting to "cold-setting".

 

[fossyant]

Jockey wheels are cheap - I'd get some Tacx ones for about £10 - sealed bearings - very nice.....

You can keep the cranks and get new chain rings - Ribble are cheap for Stronglight Dural rings

Freewheel - unless this is a cassette, then I feel you'll have a right job to try and crank one of these off, especially if it's been on for years - I once ended up using a garden hoe on the end of a spanner to remove one once....... LBS job I'd suggest for this.

 

[beanzontoast]

First - do you have old style screw-on freewheel or cassette type?
See here for the difference, although suspect the former if only a six speed block.

Next check your over lock-nut distance like this
My guess for a 30 y.o. Galaxy would be 126mm - which will just about take a modern 130 mm hub without resorting to "cold-setting".

My mistake - it's a 7 speed cassette after all - a Shimano hg50 12/28. I forgot the LBS put this on when the wheels were changed to more modern 700c. This was about 6 years back though - the timing is right.

The rear spacing is heading for 130mm. I was finding it hard to get the wheel back in, but made myself a little wooden tool (a piece of broomhandle with convex ends filed in and felt pads added to stop it scratching the paintwork. I've used this 'in the field' to hold the dropouts apart a little higher up while refitting the wheel. Over time, I think it has gently spread the distance from the original. Now I can get the wheel in just using my hands. The LBS checked the frame geometry for me last year and confirmed it's ok.

 

[beanzontoast]

Jockey wheels are cheap - I'd get some Tacx ones for about £10 - sealed bearings - very nice.....

Are these easy to fit? Would I be better off replacing the whole rear derailleur with something more modern?

 

[hubgearfreak]

sram i-motion 9. 'nuff said

 

[PpPete]

Remember "something more modern" - does not necessarily mean better/more robust.

You've got the makings of a good set up there.
Next thing to consider is whether the existing gear ratios suit you & the kind of riding you do? Do you want more & closer ratios? More lower gears for hills?
Oh yes and is the BB a square taper?

 

[beanzontoast]

Remember "something more modern" - does not necessarily mean better/more robust.

You've got the makings of a good set up there.
Next thing to consider is whether the existing gear ratios suit you & the kind of riding you do? Do you want more & closer ratios? More lower gears for hills?
Oh yes and is the BB a square taper?

I agree about the 'older can be better'. I haven't considered changing the downtube shifters or the somewhat narrow drop bars yet as I get on well with them. Just don't want to miss out on newer kit if it can give a good working life, possibly represent a performance upgrade and be reliable.

I'm pretty happy with the gearing ratios. I suppose I could thus just replace the cassette with the exact same again?

BB is indeed square taper. Do you have a suggestion for the front end based on this? The existing triple is a pretty basic affair and doesn't look like it cost much. The pedals are big, metal - and heavy!

 

[TheDoctor]

For a square-taper triple I'd suggest the Stronglight Impact. Light, fairly cheap and replacement chainrings are easily available. May as well change the BB while you're at it. Replace the cassette, get a new rear mech (a road-bike triple or any MTB mech should be fine) and a chain and you should be set for another 30-odd years!

 

[PpPete]

That Impact triple looks like good value for ali rings.
When I did my Galaxy I wanted a 52 top ring, couldn't find anything on a square taper at a reasonable price so picked up a Tiagra triple with Octalink splined BB on fleabay. It's worked OK for me so far, although I'd rather have stayed with square taper. Mine has steel rings - so it's not light but hopefully it will be durable. I'm using a Tiagra rear mech (another fleabay bargain), a 9 speed HG53 cassette, KMC 9 speed chain. All of which work fine together.
Of course the old 6 speed down tube shifters had to be used in friction mode for the extra cogs, but I've since upgraded those too.
My pedals are now M-520 (SPD's) which save a bit of weight, but what really made the difference is not the weight or the new drivetrain but putting new handbuilt wheels on. Trouble is by the time you've done all that you've spent close to the initial purchase price of the bike - and it's still a 30 y.o. machine. Love mine though....

 

[beanzontoast]

Pete - got to draw the line at changing the wheels for now. That's for the future!

Doc - Stronglight impact looks good. Are spare rings going to be available to fit it for the forseeable future, do you think? Will a 9-speed cassette (given the thinner chain) fit the space that my existing 7-speed is taking up?

 

[TheDoctor]

I would have thought so - they use 110 mm BCD, which is standard for compacts, with 74mm BCD for the inner - standard on road triples. And no, a 9 speed cassette won't go on a 7 speed hub. 8/9/10 speed cassettes are wider. If you're lucky you may have a 7 speed cassette with a 3 mm spacer on a 8/9/10 speed hub, but probably not likely.

 

[beanzontoast]

Cheers, Doc - I figured the 9-speed size might be a no-no, but more than happy with 21 gears

 

[beanzontoast]

I'd like a chain that is durable but easy to repair in the field. Any suggestions what I should go for, bearing in mind the 7-speed cassette?

 

[Amanda P]

Beanz, you're doing what I've had to do with my 1988 Galaxy. I've put on a Stronglight Impact triple (28, 28, 48, I think), and gone for 700c cassette freehub wheels - although mine will take an 8-speed cassette. (In fact, the only original parts on it now are the brake cantilevers and the frame). I started out with a Shimano megarange cassette, but found that the jump from bottom-but-one gear(26 teeth I think) to bottom (34 teeth)was really too big. So I split the cassette up and put in a 30 toother from another cassette and left out one of the smaller sprockets which I rarely used,

I like the way that SRAM chains come with an easy to use joining link. An 8-speed chain will work on your cassette fine, and you can also get spare SRAM joining links with which to repair the chain.