Gear inches - Is 2" Difference Significant

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Vorpal
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Re: Gear inches - Is 2" Difference Significant

Postby Vorpal » 30 Jun 2016, 1:16pm

I don't think I could tell the difference between 29" and 31".

Different people are comfortable with different gearing.

Like others on here, if I were selcting gearing, I'd aim for in the neighborhood of 20" on a touring bike.

In the UK, IMO, most places your current gearing is ok for most people with a light to moderate load. Hilly places: Scotland, Cornwall, Cotswolds, lower gearing is better. A heavier load would also make lower gearing better.

But that said, I have toured on gearing like that, and I might just try it and see. Afterall, the worst that happens is you walk for a bit.

Take a weekend trip with you expected load, and see how you get on. You might decide it's fine, or you might head back home on the first climb. :mrgreen:
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mercalia
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Re: Gear inches - Is 2" Difference Significant

Postby mercalia » 30 Jun 2016, 3:38pm

I have 22.5" to 108" on my 26" Dawes 1-Down just about right, anthing steeper I get off and walk , couldnt cycle continuously any way up anything that steep

Grandad
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Re: Gear inches - Is 2" Difference Significant

Postby Grandad » 30 Jun 2016, 4:35pm

As a 16 year old I had a 2 week cycling holiday with another 16 year old. We rode from Epsom to Lands End and back with 2 weeks kit in one saddlebag each. 4 speed derailleurs of 14-16-18-20 with a single 46 chainring. That's 86" to 60" and we only walked a couple of hills.

64 years later I need a 21" and avoid the really steep ones :(

reohn2
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Re: Gear inches - Is 2" Difference Significant

Postby reohn2 » 1 Jul 2016, 8:32am

PH wrote:A little number crunching thanks to Sheldon's excellent gear calc
http://www.sheldonbrown.com/gear-calc.html

50/34 and 12 - 30 cass = 30 - 112"
42 /26 and 11 - 34 cass = 20 - 103"
(based on 32mm tyre)

So, you've lost one top gear and gained a decent range of lower ones. Nothing's for free of course and some of the gaps might not suite you, though they don't bother me much and not at all when touring. OTOH I don't have much use for any gear over 90" when touring so I might not bother with the wider cassette.
You'd have to work out if your mechs would cope, but as you say they're not expensive.


Is IMO the correct answer.
If you have (double front change)STI's fitted,without changing much chainset or it costing a lot a Spa Compact double(you could go as low as a 24t inner ring)with a 40 or 42t outer,and you have a very good touring gear range. You will need to change the front mech for a road triple(Sora perhaps)using the two inner settings,as the Spa c/set uses the two inner ring positions of a triple with a chainguard in place of the outer:- http://www.spacycles.co.uk/m2b0s109p338 ... cral-Rings
You will need a un55 s/taper BB @ about £15.
So for less than £100 you've transformed your gear range,and no need to trouble Mr Surly :)
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pjclinch
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Re: Gear inches - Is 2" Difference Significant

Postby pjclinch » 1 Jul 2016, 9:16am

Another vote for a 20" bottom being good for loaded touring with hills a possibility. My wife thinks similarly. You can chug up most things in your own time with that, much lower and it would get to be quicker walking.

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pwa
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Re: Gear inches - Is 2" Difference Significant

Postby pwa » 1 Jul 2016, 9:56am

reohn2 wrote:
PH wrote:A little number crunching thanks to Sheldon's excellent gear calc
http://www.sheldonbrown.com/gear-calc.html

50/34 and 12 - 30 cass = 30 - 112"
42 /26 and 11 - 34 cass = 20 - 103"
(based on 32mm tyre)

So, you've lost one top gear and gained a decent range of lower ones. Nothing's for free of course and some of the gaps might not suite you, though they don't bother me much and not at all when touring. OTOH I don't have much use for any gear over 90" when touring so I might not bother with the wider cassette.
You'd have to work out if your mechs would cope, but as you say they're not expensive.


Is IMO the correct answer.
If you have (double front change)STI's fitted,without changing much chainset or it costing a lot a Spa Compact double(you could go as low as a 24t inner ring)with a 40 or 42t outer,and you have a very good touring gear range. You will need to change the front mech for a road triple(Sora perhaps)using the two inner settings,as the Spa c/set uses the two inner ring positions of a triple with a chainguard in place of the outer:- http://www.spacycles.co.uk/m2b0s109p338 ... cral-Rings
You will need a un55 s/taper BB @ about £15.
So for less than £100 you've transformed your gear range,and no need to trouble Mr Surly :)


+1

When I first saw a CdF I thought it was a really nice bike with the wrong gear range. 34t is just too large for the smallest ring on a road bike intended to be ridden for pleasure over hills. £100 or thereabouts is all that stands in the way of that bike becoming what it should be. Personally, I would try to make the existing front mech work with the new chainset. Keep the difference in the number of teeth between the large and small rings about the same.
Last edited by pwa on 1 Jul 2016, 10:02am, edited 1 time in total.

Psamathe
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Re: Gear inches - Is 2" Difference Significant

Postby Psamathe » 1 Jul 2016, 9:58am

reohn2 wrote:
PH wrote:A little number crunching thanks to Sheldon's excellent gear calc
http://www.sheldonbrown.com/gear-calc.html

50/34 and 12 - 30 cass = 30 - 112"
42 /26 and 11 - 34 cass = 20 - 103"
(based on 32mm tyre)

So, you've lost one top gear and gained a decent range of lower ones. Nothing's for free of course and some of the gaps might not suite you, though they don't bother me much and not at all when touring. OTOH I don't have much use for any gear over 90" when touring so I might not bother with the wider cassette.
You'd have to work out if your mechs would cope, but as you say they're not expensive.


Is IMO the correct answer.
If you have (double front change)STI's fitted,without changing much chainset or it costing a lot a Spa Compact double(you could go as low as a 24t inner ring)with a 40 or 42t outer,and you have a very good touring gear range. You will need to change the front mech for a road triple(Sora perhaps)using the two inner settings,as the Spa c/set uses the two inner ring positions of a triple with a chainguard in place of the outer:- http://www.spacycles.co.uk/m2b0s109p338 ... cral-Rings
You will need a un55 s/taper BB @ about £15.
So for less than £100 you've transformed your gear range,and no need to trouble Mr Surly :)

What actually started me thinking on the original question is that several retailers seem to be selling of their old 105 10 speed stuff really cheap and I was thinking if now might be worth getting a very discounted rear long cage derailleur. And the 2" question is that the increased capacity that would give me would be from 30t (current and max) to 32t (e.g. 105 medium cage).

But it doe seem that the way forward is the chainset change and ignore the 2" changing the rear derailleur would give (or even 3" if switching to a 9 speed MTB derailleur allowing a 34t).

Many thanks
Much to think about and all helps a lot with my thoughts on way forward.
Ian

Psamathe
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Re: Gear inches - Is 2" Difference Significant

Postby Psamathe » 1 Jul 2016, 10:01am

pwa wrote:...
When I first saw a CdF I thought it was a really nice bike with the wrong gear range. 34t is just too large for the smallest ring on a road bike intended to be ridden for pleasure over hills. £100 or thereabouts is all that stands in the way of that bike becoming what it should be.

For me, where I ride (East Anglia) the supplied ratios suite me very well. For the last few months I've not even managed to use the largest rear cog (frayed cables) and still managed quite happily.

I guess it's the load and hills that become the concern.

The other slight niggle is the toe overlap. Does not worry my in the slightest and never had any problems with it. But when laden and maybe starting off uphill I do wonder if it might be something I'd need to be more careful about.

Ian

pwa
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Re: Gear inches - Is 2" Difference Significant

Postby pwa » 1 Jul 2016, 10:09am

Psamathe wrote:
pwa wrote:...
When I first saw a CdF I thought it was a really nice bike with the wrong gear range. 34t is just too large for the smallest ring on a road bike intended to be ridden for pleasure over hills. £100 or thereabouts is all that stands in the way of that bike becoming what it should be.

For me, where I ride (East Anglia) the supplied ratios suite me very well. For the last few months I've not even managed to use the largest rear cog (frayed cables) and still managed quite happily.

I guess it's the load and hills that become the concern.

The other slight niggle is the toe overlap. Does not worry my in the slightest and never had any problems with it. But when laden and maybe starting off uphill I do wonder if it might be something I'd need to be more careful about.

Ian


It may or may not be applicable to you, but when I had a few mm of toe overlap on a bike I moved my cleats forward enough for my shoes not to touch the mudguard. It only took about 5mm and I'm not too sensitive about things like that. You may be different. Then I moved my saddle back by the same amount to keep my established sitting position. I was ready to get a shorter handlebar stem if that made the reach uncomfortable, but the change was so small that I didn't need to.

reohn2
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Re: Gear inches - Is 2" Difference Significant

Postby reohn2 » 1 Jul 2016, 10:20am

It seems the question needing an answer is,do I need/want a new bike?
If so what?
If not what gearing will provide a range of gearing for all occasions,that IMHO is a triple which will give a wide range and close enough ratios for unladen riding yet some really low ones for climbing with a load.
The choice is yours :wink:

PS, a triple set up (if you currently have STI doubles)will cost considerable more than the Spa Ultra compact double mentioned above,unless you're open to other gear changing options.
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Psamathe
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Re: Gear inches - Is 2" Difference Significant

Postby Psamathe » 1 Jul 2016, 10:24am

pwa wrote:
Psamathe wrote:
pwa wrote:...
When I first saw a CdF I thought it was a really nice bike with the wrong gear range. 34t is just too large for the smallest ring on a road bike intended to be ridden for pleasure over hills. £100 or thereabouts is all that stands in the way of that bike becoming what it should be.

For me, where I ride (East Anglia) the supplied ratios suite me very well. For the last few months I've not even managed to use the largest rear cog (frayed cables) and still managed quite happily.

I guess it's the load and hills that become the concern.

The other slight niggle is the toe overlap. Does not worry my in the slightest and never had any problems with it. But when laden and maybe starting off uphill I do wonder if it might be something I'd need to be more careful about.

Ian


It may or may not be applicable to you, but when I had a few mm of toe overlap on a bike I moved my cleats forward enough for my shoes not to touch the mudguard. It only took about 5mm and I'm not too sensitive about things like that. You may be different. Then I moved my saddle back by the same amount to keep my established sitting position. I was ready to get a shorter handlebar stem if that made the reach uncomfortable, but the change was so small that I didn't need to.

I use toe clips (though don't "need" them as for the 1st year I was perfectly happy with nothing). The toe overlap is not a great concern as it has never caused me any issues. Just I think about starting off slowly and moving the steering around to help balance as it takes longer to get up to speed ... Maybe I should do some experiments at some point.

I tend to find I get very used to things. After I got very used to nothing on pedals, 1st time with the clips I arrived home braked and came to a standstill in front of my gate and then slowly the bike with still sitting on it fell over - because I just expected my feet to move off the pedals and onto the ground but they couldn't because of the toe clips !! I came of twice whilst getting used to the toe clips and then for a long time, every junction I approached I'd be mentally thinking to get my foot out of the clips. But on "auto-pilot" for it now.

Ian

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Re: Gear inches - Is 2" Difference Significant

Postby Psamathe » 1 Jul 2016, 10:38am

reohn2 wrote:It seems the question needing an answer is,do I need/want a new bike?
If so what?
If not what gearing will provide a range of gearing for all occasions,that IMHO is a triple which will give a wide range and close enough ratios for unladen riding yet some really low ones for climbing with a load.
The choice is yours :wink:

PS, a triple set up (if you currently have STI doubles)will cost considerable more than the Spa Ultra compact double mentioned above,unless you're open to other gear changing options.

I'm more reflecting as good decisions come slowly when one has time to research (what everybody is helping me with), then reflect, consider, etc.

I assume by "other gear changing options" you mean bar end shifters (or downtube). I do like STI's and think bar end would be awkward. My reflections were more that I'd probably prefer down tube shifters (mainly because you can change both front and rear with the same hand in the one movement away from the bars). But I also wonder if my concerns are juts because I've never used bar end ones and never got used to them (something a test ride would not decide as I'd need to get used to them). And I then think that I suffer from no unusual movement restrictions and loads of other people are perfectly happy with bar end shifters so I'm sure I'd get used to them if I had to. And I probably err towards downtube shifters as i have used those on bike when I was much younger so have a degree of familiarity.

I'm not particularly seeking a new bike because mine is perfect for my current riding. And a new bike for a tour would add a lot to the cost (I'd probably need a new tent and most of my camping gear is "aged"). Plus add in front rack and front panniers and bar bag and the total cost can get quite high. So not wanting a new bike. Had everybody's answer been "you have to spend a fortune ..." then new bike would have been a consideration particularly considering 2nd hand values and all the other costs I'll have (front rack?, front panniers?, bar bag, replacing some old camping gear incl. tent, etc.).

Ian

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Re: Gear inches - Is 2" Difference Significant

Postby 531colin » 1 Jul 2016, 6:51pm

reohn2 wrote: .............You will need to change the front mech for a road triple(Sora perhaps)using the two inner settings,as the Spa c/set uses the two inner ring positions of a triple with a chainguard in place of the outer:...........


Doesn't seem to be the case....I just took a look at a prototype bike I'm going to put a few miles on, its got a 105 double front mech.
The 2 from 3 ring super compact double takes 115mm BB axle against 113mm for the triple.....that moves the inner 2 rings out just far enough for a front mech. designed for a road double chainset.

reohn2
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Re: Gear inches - Is 2" Difference Significant

Postby reohn2 » 1 Jul 2016, 8:07pm

531colin wrote:
reohn2 wrote: .............You will need to change the front mech for a road triple(Sora perhaps)using the two inner settings,as the Spa c/set uses the two inner ring positions of a triple with a chainguard in place of the outer:...........


Doesn't seem to be the case....I just took a look at a prototype bike I'm going to put a few miles on, its got a 105 double front mech.
The 2 from 3 ring super compact double takes 115mm BB axle against 113mm for the triple.....that moves the inner 2 rings out just far enough for a front mech. designed for a road double chainset.


I thought there was a possibility but wouldn't commit,glad it will :) .
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reohn2
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Re: Gear inches - Is 2" Difference Significant

Postby reohn2 » 1 Jul 2016, 10:21pm

Psamathe
Cheapest 3x10sp STI's are £140
Cheapest 10sp d/t levers £50.

Triple front mech £20

Spa's own 28/38/48 c/set £35(choice of rings add about £30)
UN54 BB £15
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