Touring Gear Ratios for Wimps!

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meconvery
Posts: 5
Joined: 19 Nov 2017, 6:48pm

Touring Gear Ratios for Wimps!

Postby meconvery » 19 Nov 2017, 6:56pm

I was wondering if anyone would know the answer to the following-


I want to buy a new touring bike but I am struggling to find one which I like the look of and has gearing low enough to allow me to climb hills whilst loaded up. A lot of my fellow cyclists seem to suffer the same problem so I am interested to see if there is anything I am missing. .

At the minute I tour on an old mountain bike with a triple with 44t/32t/22t chainrings and an 11t-32t 9 speed cassette. Lowest gear (22t chainring, 32t on cassette, 26" wheel) works out a little under 18". I'm looking for a disc braked drop bar bike with a similarly low gear, but I'm drawing a blank. Even with a road triple (typically 50t/39t/30t) and a wide range cassette (e.g. 11t-32t), the lowest gear (30t chainring, 32t cassette, 27"/700c wheel) works out a shade over 25", so significantly higher and there is no way I am getting up some of those hills out there.

The "obvious" solution seems to be to use a mountain bike triple, but most drop bar bikes I've seen spec'd in this way come with bar end shifters, which I'm not keen on. I'd prefer an STI-type brake/shift lever. Is it possible to use a mountain bike triple crank with a road triple STI brake/shift lever or will the indexing be forever out? All solutions gratefully received.

Brucey
Posts: 36089
Joined: 4 Jan 2012, 6:25pm

Re: Touring Gear Ratios for Wimps!

Postby Brucey » 19 Nov 2017, 7:19pm

fit the bike you want with a stronglight impact/sugino/spa chainset with a 110/74mm BCD. This will accept an inner ring down to 24T. Provided you choose the other chainrings to suit you will get a road triple FD to shift OK with STIs.

Shimano used to make road triple models with a 74mm BCD for the inner ring but they have gone mad (along with campagnolo) and no longer make anything much suitable that is a 'road' chainset. There are some models that are NOS and there is FC-3503 and that is about it for ones that have a 74mm BCD.

If you try to get a road triple mech to shift via a triple STI on an MTB chainset it is a route that is fraught with difficulties, and (IMHO) is best avoided.

cheers
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~~~~~~~~~~~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~

Bonefishblues
Posts: 6904
Joined: 7 Jul 2014, 9:45pm
Location: Near Bicester Oxon

Re: Touring Gear Ratios for Wimps!

Postby Bonefishblues » 19 Nov 2017, 7:23pm

As said by Brucey. I have this on my Kona.

Brucey
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Joined: 4 Jan 2012, 6:25pm

Re: Touring Gear Ratios for Wimps!

Postby Brucey » 19 Nov 2017, 7:33pm

BTW a 9s shimano MTB RD (such as RD-M772) will usually accept up to a 36T sprocket and will work with shimano 'road' shifters that are 8s or 9s or 10s (apart from tiagra 4700). This is a commonly used approach to getting a good range of gears on a bike with road shifters.

cheers
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~~~~~~~~~~~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~

keyboardmonkey
Posts: 657
Joined: 1 Dec 2009, 5:05pm
Location: Yorkshire

Re: Touring Gear Ratios for Wimps!

Postby keyboardmonkey » 19 Nov 2017, 7:57pm

Drop bar 9spd STI triple (square taper) chainset tourer with (mechanical) disc brakes:

https://www.ridgeback.co.uk/bikes/touri ... d/panorama

You still have the smaller chainset/larger rear sprocket options if you want to tinker.

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Tigerbiten
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Joined: 29 Jun 2009, 6:49am

Re: Touring Gear Ratios for Wimps!

Postby Tigerbiten » 19 Nov 2017, 8:27pm

Also something like a Surly Disk Trucker also fits all your requirements.

Flite
Posts: 266
Joined: 29 Nov 2008, 10:59pm
Location: Upper Weardale

Re: Touring Gear Ratios for Wimps!

Postby Flite » 19 Nov 2017, 9:08pm

Spa built me a bike with their audax frame but with MTB gears
Chainset 46/36/24
Cassette 12- 34
Integrated shifters (I would need to go and look at what they are..)
Diore rear mech I think
It was a couple of years ago, so no disc brakes.
Basically, I told them what I needed and left it to them to sort out what would work.
Works a treat - winches me up the endless hills of the N Pennines
And I'm female, over 70 years old!

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hondated
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Joined: 27 Mar 2008, 7:59am
Location: Eastbourne

Re: Touring Gear Ratios for Wimps!

Postby hondated » 19 Nov 2017, 10:06pm

Brucey wrote:
If you try to get a road triple mech to shift via a triple STI on an MTB chainset it is a route that is fraught with difficulties, and (IMHO) is best avoided.

cheers

Interesting comment Brucey given that Roberts built my bike with a 44t Shimano Deore XT triple chain set, a Campag front mech and Campag Veloce levers so they couldn't have struggled too much could they !

meconvery
Posts: 5
Joined: 19 Nov 2017, 6:48pm

Re: Touring Gear Ratios for Wimps!

Postby meconvery » 19 Nov 2017, 10:14pm

Thanks guys, ill take a look at the gearing suggested, as for bikes i had got to:

Ridgeback panorama-probably the closest but i would need to upgrade a few things including dynimo hub, front racks. Build is just not as nice as some others...

Genisis TdFer 30- great build, great bike, gear ratio too high, can i get a group set thats works with hills..

Genisis Td Fer 20-great build, better gear ratio but flat bar / butterfly and im really struggling with colour and just cant get excited by it.

Disc trucker- my understanding is the 54 / medium frame which i would need only comes in 26" wheels (not keen) and i was only going to start looking at bar end shifters if i ran out of options on STI

Bespoke number from SPA - i did pop in and started looking at this but stopped as my conclusion was that for me the touring bike is the one bike thats going to be left in random places and vunrable to be stolen so i didnt want it to be too pricey..(considering this for potential audax bike in a couple of years though! Great bikes).

Anyway the hunt goes on...

Brucey
Posts: 36089
Joined: 4 Jan 2012, 6:25pm

Re: Touring Gear Ratios for Wimps!

Postby Brucey » 19 Nov 2017, 10:20pm

hondated wrote:
Brucey wrote:
If you try to get a road triple mech to shift via a triple STI on an MTB chainset it is a route that is fraught with difficulties, and (IMHO) is best avoided.

cheers

Interesting comment Brucey given that Roberts built my bike with a 44t Shimano Deore XT triple chain set, a Campag front mech and Campag Veloce levers so they couldn't have struggled too much could they !


In which case you have ergos not STIs. Not the same thing at all; an easy job with most ergos.

Anyway it isn't impossible even with STIs; it is just that there are very many ways it can go wrong, and there are easier ways of solving the fundamental problem.

cheers
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~~~~~~~~~~~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~

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andrew_s
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Location: Gloucestershire

Re: Touring Gear Ratios for Wimps!

Postby andrew_s » 19 Nov 2017, 11:09pm

meconvery wrote:Disc trucker- my understanding is the 54 / medium frame which i would need only comes in 26" wheels (not keen) and i was only going to start looking at bar end shifters if i ran out of options on STI

Yes, the 54 cm frame is 26" wheel only, with the smallest 700c frame being 56 cm.

However the Truckers have a nearly horizontal top tube, so frame sizes are smaller than they appear based on seat tube size when compared with bikes with a more sloping top tube.
For example, the medium Tour de Fer (578 mm effective top tube) is pretty much the same frame size as the 58 cm Trucker (580 mm)

freeflow
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Joined: 29 Aug 2011, 1:54pm

Re: Touring Gear Ratios for Wimps!

Postby freeflow » 19 Nov 2017, 11:15pm

5703 sti with 44/32/33 delete xt chainset to deore xt shadow 9 speed rear mech and 12-36 cassette. I've posted on this forum about it many times.

ANTONISH
Posts: 1600
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Re: Touring Gear Ratios for Wimps!

Postby ANTONISH » 20 Nov 2017, 9:25am

Brucey wrote:fit the bike you want with a stronglight impact/sugino/spa chainset with a 110/74mm BCD. This will accept an inner ring down to 24T. Provided you choose the other chainrings to suit you will get a road triple FD to shift OK with STIs.

Shimano used to make road triple models with a 74mm BCD for the inner ring but they have gone mad (along with campagnolo) and no longer make anything much suitable that is a 'road' chainset. There are some models that are NOS and there is FC-3503 and that is about it for ones that have a 74mm BCD.

If you try to get a road triple mech to shift via a triple STI on an MTB chainset it is a route that is fraught with difficulties, and (IMHO) is best avoided.

cheers


I've used the impact chainset to give me 44/34/24 with 105 10s.
The rear cassette is 11 to 34 with an XT rear mech. Front mec is Ultegra which is not an ideal but works if set up carefully.
It's a pity that a mountain bike front changer can't be adapted in some way.

Brucey
Posts: 36089
Joined: 4 Jan 2012, 6:25pm

Re: Touring Gear Ratios for Wimps!

Postby Brucey » 20 Nov 2017, 10:12am

it is worth just mentioning some of the objections/potential pitfalls to using a road FD with an MTB chainset on a touring bike. In no particular order;

1) Q factor; MTB chainsets present a wider tread than a road triple (which I personally don't like on a road bike)

2) chainline; the outer chainring on an MTB triple is around 57mm (to clear the fat chainstays on MTBs). The chainline can't be adjusted much with a HTII chainset. IIRC this means the chainline on the big ring is 'perfect' onto the second or third smallest sprocket, assuming that the OLN is 135mm. If the rear hub is 130mm it is worse than that.

3) A road FD isn't usually designed to work at an MTB chainline; the shift ratio changes through the stroke which means that the index positions will only be super accurate at one chainline, and it isn't the typical MTB one.

4) some road FDs won't reach far enough to get to an MTB big ring anyway

5) the chainring intervals ought to be matched to the intended use of the FD for optimum performance

6) if you use a road FD on much smaller (MTB) chainrings than normal, on a bike with angled chainstays (big wheels, low BB) then the tail of the FD can interfere with the chainstay. (can apply to any chainset with small rings BTW)

7) chainline; with an MTB chainset the chainline onto bottom gear is poor; I think it is a much better idea (esp on a touring bike) to bring the chainset in as close as possible, so that the chainline in the (often well-used) bottom gear is better. (Maybe I've ridden up one alp too many whilst thinking about this sort of thing...? :oops: :lol: )

Needless to say point #3 applies if you fit a ST road triple chainset (such as the impact) using a BB that is too long.

An MTB mech can sometimes be made to work with road STIs if the shift ratio can be modified. It is easier to make a road FD work with MTB shifters; it is usually a case of extending the arm with the pinch bolt on it. A shiftmate can be used to make road STIs work with an MTB mech, but it can cause troubles. I have heard of some instances where a top swing MTB mech has worked with road shifters, by simply mounting the cable on the 'wrong' side of the pinch bolt.

cheers
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~~~~~~~~~~~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~

Valbrona
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Re: Touring Gear Ratios for Wimps!

Postby Valbrona » 20 Nov 2017, 12:22pm

To echo Brucey's point No.1, an MTB crankset will space your pedals as much as 2cm wider than a road crankset. Yikes!

In a sense, there are in fact more possibilities to run a 74/110 BCD triple than there used to be. The new generation of 'disc brake specific' double cranksets have chainlines typically the same as triple, so this makes conversion to triple easy with a tripleizer middle chainring. FSA BB386 disc brake specific cranksets have 30mm axles but can fit into 68mm theaded BB shells, and pretty much every other pattern of BB shell also. Fantastic.
I should coco.