Cycling UK Forum

I've seen a nice looking Dawes Galaxy (aluminium) 2017 model on sale, but it's got a 58cm frame (measured from crank to top of seatpost) and I'd have to travel to collect it (so I can't just test it by sitting on it, at least not without doing the travelling first).

I assume this'll be too big for me? I'm about 5'9 (1m74) with a 31 inch inside leg.

I've seen a comment from Brucey on here that older Galaxy's had a shorter top tube so a 58cm would work for for someone my size, but I assume the 2017 model is not falling into that category and that the more recent Galaxy's (Galaxies?) have longer top tubes for the bigger models?

Thanks!!

Are you able to ask questions of the vendor ?

If I were buying, I would want to know :

1/ The stand-over height mid way along the top tube = the stand over dimension.
2/The horizontal distance between the seat tube and the head tube = top tube length
3/The horizontal length of the the handlebar stem.
4/Available seat post height.

If the vendor is unwilling to provide any of those dimensions, you should seriously consider looking elsewhere.

Having once bought a bike 1 size too big I fully agree with jimlews. A 58cm frame sounds like it might be 2 sizes too big.

Unless vendor has measured it wrong it’s too big for you.
How tall is vendor? This only helps if it’s the right size for the vendor!
2017 it will be sloping top tube; it’s a massive bike.
I’m pretty much your size, I think you are looking for around 53cm in a bike with sloping top tube.
(Galaxy goes back to the days of horizontal top tube)

I ride a 58cm Galaxy and I’m 6ft 2in. As others have said, at 5ft 9in, it would be too big for you.

Thanks 531colin, jimlews, Cyclothesist and TrevA!

I realised it would likely be slightly too big, but I decided to buy it anyway as it was very cheap (£50!) and is in fairly good shape. It has a few minor issues (the indexing is off, it needs new brake pads and a few dings). It is on the large side for me so may get rid of it before too long, but it's certainly fine for short to middle distance trips (I did about 10 miles on it last night with no issues).

Annoyingly the chain is skipping under tension, so I'm nervous there's possibly a worn chain ring (or chain) but I'll try fiddling with the indexing to see if that fixes it.

The AL Galaxy is a lovely bike, though I still want to get the classic steel one at some point but would be likely a bit (aka a lot) more expensive

£50 is a reasonable risk to take!
If the cycle parts are in good condition you might in the future be able to transfer the parts to a better size frame for you.
When the gear “slips” is the chain slipping round on the same rear sprocket, or is it trying to change gear?
Chain slipping on the same sprocket is a classic symptom of somebody fitting a new chain to a worn cassette.
If it’s trying to change gear then adjusting the indexing is the first thing to try

531colin wrote: ↑24 May 2024, 2:08pm £50 is a reasonable risk to take!
If the cycle parts are in good condition you might in the future be able to transfer the parts to a better size frame for you.
When the gear “slips” is the chain slipping round on the same rear sprocket, or is it trying to change gear?
Chain slipping on the same sprocket is a classic symptom of somebody fitting a new chain to a worn cassette.
If it’s trying to change gear then adjusting the indexing is the first thing to try

Thanks and agreed Unfortunately it's not slipping when changing gear, but instead when pushing hard on the pedals (i.e. going uphill/moving away) which I think is a sign as you say of a worn cog. I'm not sure if it's slipping at the front or back but will try to investigate. The owner did mention that the "chain was the wrong size". But indexing is easier to fix so I'll try that first anyway!

Usually, traditional British touring bikes are longer in the top tube than the seat tube. On this basis, if you are of normal proportions, I would concur that the reach of the frame would be too much for you.

£50 is well into no-brainer/'rude not to' territory. With any suspect chain you should aim to at least identify what it is. I would look for maker's marks on the chain but I would probably also measure the chain width accurately, eg using digital vernier calipers. BTW if a sprocket is a bit worn, it may be possible to save it using a dremel tool.

Brucey wrote: ↑24 May 2024, 5:10pm £50 is well into no-brainer/'rude not to' territory. With any suspect chain you should aim to at least identify what it is. I would look for maker's marks on the chain but I would probably also measure the chain width accurately, eg using digital vernier calipers. BTW if a sprocket is a bit worn, it may be possible to save it using a dremel tool.

Thanks for the input Brucey - much appreciated as always! I'll try measuring the chain as you suggest with calipers.

Particularly appreciate the tip on saving a sprocket with a dremel - how does that work? Do you reshape each tooth using a grinding bit? Or just clean it off?

-edit- I think this thread *might* be the answer viewtopic.php?t=82046 However, doesn't sound like it's worth the hassle!

Clean the chain and see if there is anything on it you can read.
For example an 8 speed chain probably won’t work on a 10 speed cassette; and a counterfeit chain might not work at all .

jimster99 wrote: ↑24 May 2024, 11:23pm........-edit- I think this thread *might* be the answer viewtopic.php?t=82046 However, doesn't sound like it's worth the hassle!

try looking at the 'save your sprockets!' thread.

Brucey wrote: ↑25 May 2024, 10:28am

jimster99 wrote: ↑24 May 2024, 11:23pm........-edit- I think this thread *might* be the answer viewtopic.php?t=82046 However, doesn't sound like it's worth the hassle!

try looking at the 'save your sprockets!' thread.

Thanks - I found the thread (link: viewtopic.php?t=160478) but although I have a dremel it honestly sounds too hard

The front big cog has teeth that look like they came from a vampire horror movie. The other cogs look OK (to my untrained eye). Looks like I have a 48-38-28 triple chainring (not sure if I can just change the big cog by itself). Should I do the chain and rear cassette at the same time? Never actually changed a chainring before but it looks easy. I've also included a pic of the bike itself - needs a clean but otherwise looks OK! Finally, do chainrings come in different sizes or will any 48-38-28 from Shimao/Sram do the job? Thanks

Front crankset pic one:
Front crankset pic two (showing the small chainring)
Rear cassette (looks OK to me)
The bike itself

Looking at the state of the large chainring, and the fit of the chain on the inner and middle chainrings, I would say that the whole lot is worn out.

You can probably carry on riding it as it is for a while, which could be a year if your mileage isn't too high, but you'll need to change the chain, chainrings and cassette in the end. Do this as a full change - don't try changing them separately.
Chainrings aren't as sensitive, but a new chain on an old cassette, or a new cassette with an old chain will skip.

When replacing chainrings, it can often be as cheap to replace the whole chainset as it is to replace the rings individually.
I'd suggest something like this: https://www.spacycles.co.uk/m8b0s109p20 ... e-Chainset (£41)
7-speed cassettes can be had for under £15, and chains for under £10 (Tredz)

Chainrings should match the chainset, both in regards to the number of arms/bolt holes, and the diameter of the circles through the bolt centres. It's simplest to measure between adjacent bolt centres and look up the bolt circle diameter here.
Of course, if your chainrings are riveted on rather than bolted, you'll need a new chainset anyway.