Dawes Horizon upgrade query

[Dales_tourer]

My Dawes Horizon is due for an refurb/upgrade after 15+ years of good service. The frame (Reynolds 531) is still in good condition so I was thinking of getting the wheels and drivetrain replaced. I currently have butterfly handlebars (which I prefer to drop bars), and would like lower gearing than I currently have (since most of my touring seems to be in the hills these days) and lighter wheels.

My LBS has recommended a Sora group set (9 speed) with MTB shifters, but I'm a bit worried that the gearing (50/39/30 chainring) is going to be too high for me. Any suggestions for alternatives? Would a standard MTB group set fit a touring frame? If so, what would be a good option for touring?

Also, what are the options on brakes?

Any help appreciated!

[Brucey]

you don't say how low your current gears are or indeed how low you think you might need to go to.

But arguably an MTB groupset is easier to fit if you are going to use flat bars; most flat bar shifters won't work (say) a Sora front mech.

My suggestion would be that you look at the Alivio group options.

This page

http://productinfo.shimano.com/lineupchart.html

has a link allowing you to download the full catalogue as a pdf.

If you look on p16 and p32 then you can see the lineup within the Alivio group. You can see that you can mix and match with different chainsets as well as 9s cassettes to give the gears you want.

Alivio is fine but if you want to go with more expensive parts then XT or LX trekking parts may suit you, but this means going 10s.

In 9s you can mix and match between groupsets to a great extent, so an XT shadow rear derailleur (for 9s) will work with Alivio shifters etc.

You will have to use V brakes with most of the MTB/trekking brake levers, but a few of them may have adjustable cable pull in which case you might be able to use cantis instead (you have canti bosses, right?).

Another option is to use the 3x9 parts on p65; there is a flat bar shifter set with (I think) a 'road' cable pull front mech. If you use this with (say) a Spa triple chainset you can have 26-36-46 (or lower even) flat bar shifters, and the brakes/brake levers of your choice.

cheers

[Bicycler]

I'm actually a bit confused because I'm not sure an indexed MTB shifter should shift a road (eg. Sora) front mech

But, yes, you can fit a mountain bike groupset to a touring bike. I tend to think the lower the better (I rarely run out of gears) even the lowest commonly available triple combination which would be a 44-32-22 and 11-34 cassette would give a gear range of 17-104" which is high enough for me. The other extreme would be to choose a narrower rear cassette to mean less of a jump between gears. An 11-28 cassette would give the same top gear with a 20" bottom gear. If you mainly ride unladen maybe that is a bit low for you but there are options for bigger front rings. There's plenty of choice of sensible gears for mountain bikes!

I you are using MTB STI shifters then they will have the correct pull for V-brakes. Hopefully your Horizon isn't old enough for pivot spacing to be an issue and v-brakes will just fit straight on. There's no reason to have anything other than v-brakes on a touring bike if you have MTB brake levers and rim brakes.

[Bonefishblues]

OP would you mind if I piggy- backed on your thread later? I've something of a similar scenario and it might be of interest.

[Dales_tourer]

Thanks - that link is very helpful!

I think my current smallest chainring is 28T, and ideally I'd like something closer to my MTB 22T chainring, so the Alivio or Deore trekking options look very promising.

Would a 10 speed cassette fit an older bike? I currently only have a 7 speed cassette.

Apologies for being vague about spec - this is all very new to me!

[beardy]

Would a 10 speed cassette fit an older bike? I currently only have a 7 speed cassette.

You have said that you want to replace the wheels (as well as the drivetrain) so you can choose whether those wheels are 7, 10 or any other speed that you wish.

The ten speed will almost certainly fit in a 15 year old frame.

The Sora front crankset doesnt fit the bill for what you wish. A Stronglight or Spa will suit you much better.

http://www.spacycles.co.uk/products.php ... 0s109p2000

you can replace the inner ring with anything down to 24 teeth or you can buy their more MTB style crankset for even lower gearing.

If it was my bike I would stay with the 7 speed style hub that you have because they are stronger wheels however if you can not find a 7 speed hub then you may be forced into going for eight or nine. No point in sticking with 7 speed if that uses a more modern 8,9,10 speed hub.

The problem with 7 speed is you may not be able to buy it "off the shelf" as a whole system and some thought and shopping around is needed. The plus side is you can get good durable kit very cheaply.

I am not adverse to some fancy 9 speed on my lightweight bike but for the tourer it makes sense to stay with 7 speed, if you can find it.

[Bicycler]

7 speed hubs came in 126mm, 130mm and 135mm varieties. Modern road wheels/hubs are 130mm, modern mtb/touring wheels are 135mm. Either will accept a 7, 8, 9 or 10 speed cassette but the MTB 135mm hubs produce a stronger wheel with less dish. You need to measure the over locknut distance of your frame http://sheldonbrown.com/gloss_sp-ss.html#spacing

If it is 126m then you will be able to squeeze a 130mm road wheel in or alternatively you can ask the shop to "cold set" the frame to 135mm to fit a stronger 135mm wheel.

[mercalia]

I think the Horizon chainset was 48,38,28 -that what my 1999 was & was 7 speed

[fatboy]

Given you've not got drops then you can use an MTB group set and get the low gears that you want. Sora is if you've got drops (they probably do a flat bar version but why would you want that).
If you ever wonder about the demise of the LBS this can be why. The OP went in asking for low gears on a flat bar bike and was offered a road group set. Ridiculous! Having said all that you can lower the gears on a Sora chain set by running a smaller inner ring (I do on my road bike) but Sora is an external BB chain set which are poorer for longevity than a conventional one.

Hope you can find your way to what you want.

[Dales_tourer]

Thanks all. Some really useful info.

Definitely need to go back to the drawing board before I part with my cash!