Gear inches - Is 2" Difference Significant

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Psamathe
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Gear inches - Is 2" Difference Significant

Postby Psamathe » 29 Jun 2016, 7:17pm

Love my bike for cycling round flatlandia. But beginning to think about touring and wondering about the gearing.

I would be camping and it would be a long tour (e.g. for the summer starting when the weather/campsites permitted and ending when they no longer permitted). I'm 60 and not some mega strong cyclist.

I would be "gentle touring" (i.e. no rush to complete anything within a short timeframe). Shorter distances, happy to get off and push if need be - if it takes a bit longer to get there that's fine.

Qu 1. My current lowest gear inches is 31". With a fairly minor/cheap change I could get that down to 29". Is that 2" significant or irrelevant. Or does every little help.

Qu 2. Am I daft thinking about camping touring with such gearing ?

(It's a Croix de Fer with 50/34 Compact Double and 12-30 rear cassette)
I've tried looking at gearing during my normal rides but I never really know which gear I'm in, just a vague impression and something that gives me a comfortable cadence. I've not been able to successfully ride along and change and think 'that's x"' difference.

Many thanks
Ian

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NATURAL ANKLING
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Re: Gear inches - Is 2" Difference Significant

Postby NATURAL ANKLING » 29 Jun 2016, 7:22pm

Hi,
I would be happier with 20 " for your age / self supporting touring.
That 2" is not worth the money you will not notice if at all.
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pwa
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Re: Gear inches - Is 2" Difference Significant

Postby pwa » 29 Jun 2016, 7:30pm

2 inch would be about half a gear, which you might appreciate on a long draggy climb. But ideally you would change the chainset and bottom bracket to get something more like 26 /40, which would make it significantly easier.

Psamathe
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Re: Gear inches - Is 2" Difference Significant

Postby Psamathe » 29 Jun 2016, 7:33pm

NATURAL ANKLING wrote:Hi,
I would be happier with 20 " for your age / self supporting touring.
That 2" is not worth the money you will not notice if at all.

Many thanks. I becomes a difficult choice as to do it "properly" would mean significant costs and I begin to think in terms of the cost being a significant way towards e.g. Surley LHT (and then I'd have something where I know all the bearings, etc. are 100% (new)). And the "change bike" option is not the full cost of the bike as existing bike or LHT would have 2nd hand value to further offset the cost (I appreciate there are alternatives to LHT but using that as a "might cost" point).

Thanks
Ian

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NATURAL ANKLING
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Re: Gear inches - Is 2" Difference Significant

Postby NATURAL ANKLING » 29 Jun 2016, 7:34pm

Hi,
I would go for 20 od to 100" gearing with luggage for you fitness / age.

Ideally triple clanger up front.
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pwa
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Re: Gear inches - Is 2" Difference Significant

Postby pwa » 29 Jun 2016, 7:43pm

If you end up splashing out on a LHT, why not talk to Spa Cycles, who will make one up the way you want it. You could compare it with one of their own brand tourers.

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Re: Gear inches - Is 2" Difference Significant

Postby NATURAL ANKLING » 29 Jun 2016, 7:46pm

Hi,
At 57 and do all my training 37 - 48 miles, three times a week with a 22/24 kg bike flat out, up to and over 85% of my max heart rate for 3 hrs.
I am 76 / 80 kgs.....I use a minimum 30 " on the skip trainer and 27" min on the tourer (longer courses).
I use 30" min on 4000' over 28 miles with several 30% too but that's silly.

I would not like to do with a 30" all day even at a reduced rate,
My bottom is 18.5" and I only really need that for off road up hill rutted track.

More enjoyable if you can spin freely and not keep getting off which I do now and again on a long day :?

Sitting up and relaxing makes you feel better if you have a low gear.
But there is always walking :)
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Psamathe
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Re: Gear inches - Is 2" Difference Significant

Postby Psamathe » 29 Jun 2016, 7:57pm

pwa wrote:If you end up splashing out on a LHT, why not talk to Spa Cycles, who will make one up the way you want it. You could compare it with one of their own brand tourers.

Not set on any particular manufacturer/model (and I quite detest the graphics on the Surley). It's more that I think best decisions are often made by reflecting and considering all options. I only really used the Surley as "more suitable touring bike might cost £xxxx).

The one trouble I have with "will make what you want" is that when I have a choice "what I want" can get more costly. I'm from the generation when Dell published their computer prices in a table and a bigger monitor only adds a small amount and more memory does not add much cost and a bigger disk is a good plan and only slightly increases the price ... and you end-up at the bottom right corner of the table at the top spec, most expensive.

Ian

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Re: Gear inches - Is 2" Difference Significant

Postby PH » 29 Jun 2016, 8:24pm

I wouldn't want to tour with a camping load with that gearing, I prefer something around 20" as a lowest gear, but I'm not you. I find on the steepest hills, I can get off and push the bike at a similar speed as I can ride, whatever the gearing.
Psamathe wrote:Many thanks. I becomes a difficult choice as to do it "properly" would mean significant costs and I begin to think in terms of the cost being a significant way towards e.g. Surley LHT (and then I'd have something where I know all the bearings, etc. are 100% (new)).


Depends what needs changing, what you consider properly and how much you consider a significant cost.
Super compact chainset and BB like this one come to around £75, and give a bottom gear in the mid 20s, what more would you need to change?
http://www.spacycles.co.uk/m2b0s109p338 ... cral-Rings

And the "change bike" option is not the full cost of the bike as existing bike or LHT would have 2nd hand value to further offset the cost

When making the price comparison, don't forget that any part worn consumables you take off, chain, rings, cassette, aren't wasted as they can go back on at a later date.

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horizon
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Re: Gear inches - Is 2" Difference Significant

Postby horizon » 29 Jun 2016, 8:35pm

How long is a piece of string? I think we're all thinking that you mean say 16 kg - 18 kg on the bike. But many people camp with much less and as you go down in weight you set off a virtuous circle - the front panniers can go, the front racks follow, experience means you take less and a credit card means you can escape the worst weather - so less or lighter gear. There are lots of threads on here about weight.

Your gears are obviously too high but when you get down to say 23" (or say a 22T granny) you are talking about being able to cycle up most hills even with a fair old weight. But you could walk up the steeper hills, avoid mountainous terrain, reduce your daily mileage, tour in warmer climes, keep your fitness up and your (and your bike's) weight down.

It all comes down to a combination of factors.
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Re: Gear inches - Is 2" Difference Significant

Postby Psamathe » 29 Jun 2016, 8:46pm

PH wrote:...
Depends what needs changing, what you consider properly and how much you consider a significant cost.
Super compact chainset and BB like this one come to around £75, and give a bottom gear in the mid 20s, what more would you need to change?
http://www.spacycles.co.uk/m2b0s109p338 ... cral-Rings

And the "change bike" option is not the full cost of the bike as existing bike or LHT would have 2nd hand value to further offset the cost

When making the price comparison, don't forget that any part worn consumables you take off, chain, rings, cassette, aren't wasted as they can go back on at a later date.

I'd been assuming I'd need to switch to a triple which would mean changing STIs as well - which is the expensive bit (I have doubts I'd get on with bar end shifters - which of course becomes an issue with a new touring bike), which means I might have to just learn to use them ... Hence the starting to consider options very early.

Not so concerned about changing cassette and chain (they wear out anyway) and derailleur & front mech are not too expensive (and I've already written off one derailleur - mine don't last forever).

I wonder if the super-compact might not give the faster ratios - hence my assumption about super compact doubles (where I'd only have a 40t large chainring). But maybe I've got the wrong expectation of loaded touring speed as my minimally loaded (1 pannier 5Kg) 30 miles rides around flat countryside average not much below 14 mph - which I don't expect to match with loaded touring.

So I can see it would give the granny gear but my "proper" would be to keep as much of the bottom gearing as well.

But I'm not experience at this, hence asking for advice from others.

Ian

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Re: Gear inches - Is 2" Difference Significant

Postby PH » 29 Jun 2016, 9:16pm

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.

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Re: Gear inches - Is 2" Difference Significant

Postby rmurphy195 » 29 Jun 2016, 9:36pm

NATURAL ANKLING wrote:Hi,
I would be happier with 20 " for your age / self supporting touring.
That 2" is not worth the money you will not notice if at all.


What he said, is what I use! On a triple,8-speed. Maybe you can get a rear cassette with a very big (dinner-plate) sprocket on it, and smaller chainrings
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Re: Gear inches - Is 2" Difference Significant

Postby iviehoff » 30 Jun 2016, 11:34am

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.

As this demonstrates, these days you can get perfectly adequate gear ranges for a cycle camping bike with a double chainset. You don't need the high gears. I've ridden a bike with an even smaller outer chain ring.

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Re: Gear inches - Is 2" Difference Significant

Postby whoof » 30 Jun 2016, 1:08pm

I would second (or maybe 3rd) looking into changing to a double with around a 20" bottom gear. Without it I think you would find any hill that is either long or steep a struggle. Also even hills that on an unloaded bike seem easy when carrying full camping gear brings you down to a relative crawl.
20" or there abouts seems to be what most people use as a bottom gear for such touring. Personally I have 22" to 94" range. Just ridden a two week tour including climbing the Grossglockner, which has about 15km of climbing at about 9% or greater with camping gear and was fine, but I am a little younger than you.

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