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Dawes Galaxy Twin - gears

Tim Benge-Abbott2025-06-15 19:32:52

We've got a Dawes Galaxy Twin (c.2019 model). It's set up with Shimano Sora Triple STI levers but these don't seem to have enough travel to access all three chainrings. The front derailleur is a Shimano Alivio which (disconnected from the control wire) appears to have plenty of travel but I've never been able to set this all up to be able to change across all three chainrings so have settled for now with just accessing the large and middle ring.

Has anyone else here with a Galaxy Twin managed to get it to change reliably across all three chainrings?

If not, I'm wondering about giving up on triple and just going for a 2 ring set-up with a 12-36 rear (12-32 currently) and 48-34 front (unless anyone thinks 48-32 would work!) Or 11-36 and 44-32.

All advice gladly received as we weigh up the options.

Lawrence McPhillips2025-06-15 22:01:16

Front derailleurs can be a bit of a hassle to get working correctly at the best of times.  If the bike was sold originally with Sora levers and an Alivio front derailleur, then I'd expect it to work.  BUT if the FD has been swapped out at some point, that may be the issue.  I'm not sure, but I know that some Shimano combinations don't work well together.

 

A road FD will work fine with a road  shifter and an MTB FD is fine with an MTB shifter.  Combining a road shifter with an MTB FD (or vice versa) can be problematic.  To the best of my knowledge, the chain ring spacing stays the same and the shifter pull ratio is the same, but somehow mixing road / MTB FD's & shifters doesn't seen to work well.

One possible 'bodge' is to try routing the FD cable on the other ('wrong') side of the clamp bolt.

 

At the risk of teaching you to suck eggs, have you tied the obvious things like check limit screws or even moving  the FD by hand to ensure there is actually enough 'throw' to reach all three chainrings?

 

BTW: There are quite a few decent You Tube videos on setting up FD - this guy's spiel is quite good: https://youtu.be/5tpPOZam78M?si=PDGbG2b4C1c8cVV2

His tip about minor 'tweaks'to the FD plates has worked for me in the past.

Stick with it - you will get there.

Tim Benge-Abbott2025-06-16 15:08:14

Thanks – this is so helpful. I hadn't considered that the lever ratio throw of the FD might not match that of the STI lever. So if the FD is designed for more leverage, and therefore longer throw than the STI lever, the relative travel of each will be different and they won't work together.

I'd have thought the Sora triple should be a pretty reliable design so I'll have a look to see if there's a FD that's likely to be a better match.

 

Lawrence McPhillips2025-06-16 16:30:10

Glad to be of some (limited) help.  I've had quite a lot of 'fun' over the years mixing and matching components laugh.

 

You'll almost certainly be able to turn up a used Sora FD on eBay as so many people want to go to a 1 chainring system these days and they just dispose of their old kit. I have a hybrid bike with drop bars and a Shimano 3 x 9 speed Tiagra groupset so I'd expect a Tiagra FD would work for you too.

 

You might find this article helpful in explaining various aspects with greater clarity than I could manage: https://bike.bikegremlin.com/1297/bicycle-front-derailleur-compatibility/

 

It points out some things to consider when mixing components.  The good news is that once you have got the FD sorted out, they rarely need much attention other than cable adjustment now and again.

 

Don't you just love the 'simplicity' of modern bicycles .......

Russ Valentine2025-06-18 18:00:56
That's interesting Tim, I've 2 (don't ask) Galaxy twins, both about 2016 in age and have the same problem. One works fine over the 3 front sprockets, the other not. Although both changer and lever appear to be identical. I can't work it out either.