Advice on gearing

General cycling advice ( NOT technical ! )
iandriver
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Re: Advice on gearing

Post by iandriver »

Sounds to me like you just need to change a couple of chainrings on the existing chainset.

Plenty of people running 26 39 50 rings in road chainsets.
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MikeF
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Re: Advice on gearing

Post by MikeF »

Vantage wrote: 29 Sep 2022, 11:11am
The biggest 8 speed cassette I can find without delving deep into the interweb is a shimano 11-34t. Anywhere between £16 and £20.
The problem with the 11-34 is the big jump from the 28 to 34 sprocket
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Vantage
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Re: Advice on gearing

Post by Vantage »

MikeF wrote: 29 Sep 2022, 9:24pm
Vantage wrote: 29 Sep 2022, 11:11am
The biggest 8 speed cassette I can find without delving deep into the interweb is a shimano 11-34t. Anywhere between £16 and £20.
The problem with the 11-34 is the big jump from the 28 to 34 sprocket
Ah yes. I remember it well.
Bill


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roubaixtuesday
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Re: Advice on gearing

Post by roubaixtuesday »

MikeF wrote: 29 Sep 2022, 9:24pm
Vantage wrote: 29 Sep 2022, 11:11am
The biggest 8 speed cassette I can find without delving deep into the interweb is a shimano 11-34t. Anywhere between £16 and £20.
The problem with the 11-34 is the big jump from the 28 to 34 sprocket
I don't find a similar 30-36 jump a problem on 11-36 9 speed.

Once you're on a 30 rear you're basically grovelling anyway, so a big jump is fine. All that matters is the lowest gear for laden touring, everything sense is detail.

Just my own preference I hasten to add - each to their own.
simonhill
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Re: Advice on gearing

Post by simonhill »

That's why it's important to change down early particularly when loaded.

How many have found they can't get into their lowest gear when struggling up a hill because you are having to put too much strain on the drive train.

It's even more important when loaded to look ahead and plan. For a slow one like me, better too low, changing up is usually easier.

Using your gears correctly is as important as having the right gears.
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Cugel
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Re: Advice on gearing

Post by Cugel »

iandriver wrote: 29 Sep 2022, 7:03pm Sounds to me like you just need to change a couple of chainrings on the existing chainset.

Plenty of people running 26 39 50 rings in road chainsets.
That does seem the obvious answer - although personally I'd reduce the big chain ring to a 44 and the small chain ring to 24 or even 22, if the primary objective is getting up the steeps on a fully loaded bike via twiddle rather than a grind.

Folk think they "need" an 11 sprocket and a 53 ring to "cane it down the slopes" but what they really need is to save their energy for the next steep whilst tucking in all their parts when going down, to decrease air resistance and hence speed.

Or, being a tourist, they could just sit up, go slower downhill and spend more time gazing at the nice scenery. :-)

Perhaps someone will provide a graphical illustration but, as I recall, it would take 200 watts or more pedalling energy to increase the speed of a loaded touring bike (over that provided by gravity alone) by just 1 or 2 mph when going down a significant slope already at a significant gravity-driven velocity ....... ? You get more speed by tucking the flailing legs into the frame triangle and crouching down over the bars with elbows tucked in rather than by flailing your legs in the wind as you pedal a Great Big Gear.

Cugel
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PH
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Re: Advice on gearing

Post by PH »

PeterJ wrote: 29 Sep 2022, 9:27am I'm inclined to let the shop purchase the bits. He's always been very good value, and occasionally will give me a small part for free. And as you say, I'd prefer him to have full responsibility for making sure it all works - I'd imagine he'd be happier with this arrangement too.

It would be great if the forum experts could come up with a list of requirements I can hand to the shop.

Thanks again.
I think you need to be talking to the bike shop ASAP to see what they suggest and can offer. My experience isn't comprehensive, but I haven't used one that would be happy with a customer handing them a list of parts!
You may find them reluctant to stray from the standard. That isn't surprising, I might do something with a 99% chance of it working, but I wouldn't do it for someone else, that 1% could see a return and there goes the profit. Plus they may want to work with parts they and their distributers stock.
This isn't a criticism of the good folk who work in bike shops, just an acceptance that time is money and the sort of effort I might put into sourcing and getting non matched parts to work, could result in an extortionate bill if carried out at shop rates. Then there's the definition of working, for example - I ran 50/40/24 on an Audax bike, it gave me plenty of close gears in the range I'd spend most of my miles, and a really low bail out gear that I could happily spin at walking pace, but I couldn't get it to reliably work without a chain catcher to stop the overshoot from middle to small and there was a bit of a technique for shifting smoothly back from small to middle. A bike shop is likely to want to offer something that always works, even if the customer says they'll accept the compromise.
Or, your bike shop may be completely different...
slowster
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Re: Advice on gearing

Post by slowster »

I agree with PH's comments.

When deviating from Shimano specifications, some tinkering and trial and error may be needed to get the best performance. That can be unpredictably time consuming, and could significantly add to the cost if the work is done by a shop. Sometimes it might even be necessary to experiment with different components, e.g. different bottom bracket lengths or front derailleurs.

For those of us who DIY, our time does not cost anything, and we take the risk that things might not ultimately work or that we might experience difficulties - and maybe extra expense - completing the task.

Spa Cycles are probably the exception, because they routinely assemble their bikes with non-standard drivetrains, and so they already have a good knowledge of what mixes of Shimano and non-Shimano/non-groupset parts will work (and have stocks of them) and how to set them up to get the best performance. They stock various wide ratio 8 speed cassettes, including a Sunrace 11-40 and Shimano 11-34, as well as various Shimano chainsets and own brand chainsets with custom chainring combinations. If you are anywhere near Harrogate, I would suggest you take your bike to them and ask about options and recommendations for lowering your gears.
Rob D
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Re: Advice on gearing

Post by Rob D »

A bit late to the party but I've changed to 22 on the front, 36 on the back. For touring, seems really good. It's on a Claud Butler Dalesman. Originally 26 front, 32 back. Big improvement.
Just back from 3 months in Norway, Finland and Sweden, where it was given a good test!
De Sisti
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Re: Advice on gearing

Post by De Sisti »

Cugel wrote: 30 Sep 2022, 10:52am That does seem the obvious answer - although personally I'd reduce the big chain ring to a 44 and the small chain ring to 24 or even 22, if the primary objective is getting up the steeps on a fully loaded bike via twiddle rather than a grind.

Folk think they "need" an 11 sprocket and a 53 ring to "cane it down the slopes" but what they really need is to save their energy for the next steep climb
This is very good advice for those unsure of gearing.

I would recommend getting chainsets (with your choice of chainrings) from Spa Cycles.
iandriver
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Re: Advice on gearing

Post by iandriver »

Cugel wrote: 30 Sep 2022, 10:52am
iandriver wrote: 29 Sep 2022, 7:03pm Sounds to me like you just need to change a couple of chainrings on the existing chainset.

Plenty of people running 26 39 50 rings in road chainsets.
That does seem the obvious answer - although personally I'd reduce the big chain ring to a 44 and the small chain ring to 24 or even 22, if the primary objective is getting up the steeps on a fully loaded bike via twiddle rather than a grind.

Cugel
Pretty much what I run on by tourer. 22, 36, 42. I found a 32 a bit too small on the middle ring, too much time on the 11t at the back. A 36 gave nice cruising gears in a 15 ish out the back with nice chainlines.
Run 26,39,50 on my audax.

No need for new chainsets or bbs for the op, just swap a couple of rings, rear cassette and new chain.
PJ520
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Re: Advice on gearing

Post by PJ520 »

Leonard Lee has what seems to me good advice
You only live once, which is enough if you do it right. - Mae West
gregoryoftours
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Re: Advice on gearing

Post by gregoryoftours »

I absolutely hate the idea of getting off and pushing! I'd say that 28/32 isn't a particularly low gear for loaded touring. I tend to tour on old steel mountain bikes. My chainset is 44/32/22, cassette is 9 speed 11/34. I've never really missed having a higher gear than 44/11, and 22/34 is about the lowest gear I can push without going slower than I can balance on the bike properly. That gear was low enough to get me over hardknott pass fully loaded with camping equipment.

If top speed on the flat isn't too much of an issue for you I'd consider that setup. You can always find that out by seeing what a similar gear on your current setup feels like as a top gear. Eg 12t cog on the back with a 48 big ring is the same ratio as 44/11.

If that feels ok as a top gear then my first step would be to change the chainset to 44/32/22. Depending on the model of your existing chainset it will probsbly not need a new bottom bracket. A new chainset will probably be cheaper than swapping the 3 rings.

You may find you don't need the 34 sprocket on the back so could save yourself a bit of money and keep your existing cassette and chain. I'd say you'd probably not have to change your front derailleur, just lower it. You may have to shorten your chain a bit, and your rear derailleur will have to take a little more slack which should be accommodated for if it's not too old a model of deore mech.
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Vantage
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Re: Advice on gearing

Post by Vantage »

I'd say a new cassette with a bigger low gear would be cheaper than a new chainset and possible bottom bracket.
Speed on a touring bike seems a bit silly as the slower you go the more you see which afaics, is what touring is all about.
Bill


“Ride as much or as little, or as long or as short as you feel. But ride.” ~ Eddy Merckx
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Tigerbiten
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Re: Advice on gearing

Post by Tigerbiten »

My thinking on a 3x8 setup for me.
I don't like the big steps between the gears on a cassette that starts 11-13-15-18-, so I'd go for one that starts 12-14-16-18-.
With a 12t small sprocket that almost locks me into a 48t big chainring.
With a triple, I'd want to maximize the capacity and hope that I still get crisp shifting, so that's 48-36-24.
I'd want to maximize the range on a cassette start with a 12t sprocket while keeping the gaps between the gears roughly even, so the 12-32 is the optimal one.
Now this is where I'd hope the LBS can swap the 32t sprocket for a 34t sprocket giving me a 12-34 cassette.
I don't mind a big step between gears at the bottom end of the gear range, it just means I'll grovel uphill in first a bit longer.
That gives me:- 5 grovelling uphill climbing gears 3.5-8 mph, 5 easy flatland gears 8-16 mph and 3 fun downhill gears 16-26 mph.

As for cadence, you're on a plain tour not the tour de france.
So the aim is to go from A-B in a reasonable time using the minimal energy.
Not to go from A-B as quickly as possible.
So a comfortable cadence with a light pedal pressure is ideal.
My optimal cadence zone is around 70-80 rpm.
Once I'm much above 80 rpm my efficiency tanks and I end up going slower in the long run as I run out of energy.

Luck ......... :D
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