Double or triple chainset?

[User482]

So we're now having to fit MTB rear mechs and cassettes, with attendant cost and jumps between ratios (I certainly wouldn't want to use my 11-32 MTB cassette for road work). Sounds like a totally uncecessary compromise to me...

 

[Cubist]

So we're now having to fit MTB rear mechs and cassettes, with attendant cost and jumps between ratios (I certainly wouldn't want to use my 11-32 MTB cassette for road work). Sounds like a totally uncecessary compromise to me...

Exactly. My compact has a 36 32 lowest gear, which can be a pain on steep hills, but my biggest bugbear is that fact that I have to do a double change every time I change chainrings. An 11-32 cassette does indeed give low gerars, but it also gives a bloody lumpy set of ratios.


As soon as my C2W vouchers get here I'm gonna order me a triple (with a 30-27 bottom gear). Yes it's the same bottom gear as the compact I now have, but at least it'll have smoother ratios.

 

[MacB]

Another female here. I'm not going to get into the debate, but I would like to just point out that it isn't absolute strength that you need, it is power to weight ratio - these poor men have lug their greater weight up the hills, while you and I are lightweights and don't have so much to shift! (This is why my boyfriend, who is 5' 5" and about 9 stone, is very good up hills, he has the strength but not much weight to shift) The tables are turned on the downhills, when gravity is a help rather than a hinderance...

For the record, I have a standard chainring on my road bike, with a 9 speed cassette. I have no idea what gear ratios I have, though.

very true for climbing and I'd throw in stamina for keeping up a pace on flat/rolling terrain. I may be physically fairly strong but my power to weight ratio and stamina(currently) put me firmly in the weakling category. I will never have a climbers physique but I can certainly do something about the ratio and the stamina.

I suspect that if I do achieve the fitness, stamina and weight levels I'd like then the inner ring on my roadbike won't get much use, if at all. Still rather have it there than not though.

 

[dellzeqq]

it falls to me to point out that you are all wrong (except, possibly, for User482.......)

It's not too difficult to work out what kind of a bottom gear you're going to need. For some it will be a 30/27, or even a 38/34, and for others it will be a 39/21. It's not too difficult to work out what your top gear needs to be - for most of us it will be something between 53/11 and 50/13 (I think I'm right in saying that Merckx smallest sprocket had thirteen teeth).

Once you've done that all you need to do is to sit down with a pen and paper (and a calculator if, like me, you're a bit past this kind of thing) and see how you can fill the gap between the lowest and the highest in the smoothest possible way. If you were of a modern, technological persuasion you could visit the incomparable Sheldon Brown http://www.sheldonbrown.com/gears/

Now - putting a triple 48/38/28 in and a standard 9 speed 12-27 gives you a range of gear inches from 28 to 108 - but it's not all good. There's a 13.3% leap from 48/17 to 48/15. You can reduce the leap by going from 48/17 to 38/13 to 38/12, but that's a bit of a faff.

Putting a compact 50/34 in with the same 9 speed 12/27 gives you the same 13.3% leap, but it denies you the 'faff' alternative.

However - if you can possibly get away with a lowest ratio of 28/21 (using a 48/38/28 teamed with a 12/21 nine speed cassette), your lowest gear will be 35 gear inches, and the leaps in the middle range will be of the order of seven percent - which makes for a far, far more comfortable ride. If you can do the clever thing and change up and down simultaneously it will be a little like driving one of those variable belt cars.

I ride with people who use all kinds of wide cassette ratios. It looks like terribly hard work.

 

[albion]

I suspect that if I do achieve the fitness, stamina and weight levels I'd like then the inner ring on my roadbike won't get much use, if at all. Still rather have it there than not though.

When I achieve a level of fitness where the power is 'on tap' I really have to hold back in that my knee soon becomes a goner.

It's also ok having smooth gear changes, but hills themselves certainly are seldom smooth. I'm also sure that it is the lack of a 'granny gear' that both retires many new cyclists and makes roadies a growing minority in some areas of the country.

 

[threebikesmcginty]

I like the compact set-up, I use a 34/50 12/27 and find it's fine for most of my cycling, I know there's a fair bit of cross over but the overall range is pretty good. MacB's weird set-up's with 46t and 11 30 etc are fine if you're building a bike, as he does every couple of weeks , but most folks will just want to pick up a stock item. If I was riding long distances and carrying loads of stuff, or when I get old(er) and knackered(er) then I'd probably go for a triple but for my everyday mucking about at the moment a compact is fine.

 

[ColinJ]

I suspect that if I do achieve the fitness, stamina and weight levels I'd like then the inner ring on my roadbike won't get much use, if at all. Still rather have it there than not though.

I managed it about 8 years ago. I spent a whole year not using the inner rings on my road bike or MTB. I was climbing hills in 39/26 then that I use 30/28 on now.

As you say though - it's nice to have low gears in reserve. I didn't do many long rides that year, and I certainly didn't experience a 20 mph headwind on a killer 20% climb 60 miles into a ride, something that my 30/28 gear has saved me on since then.

 

[benb]

When I achieve a level of fitness where the power is 'on tap' I really have to hold back in that my knee soon becomes a goner.

It's also ok having smooth gear changes, but hills themselves certainly are seldom smooth. I'm also sure that it is the lack of a 'granny gear' that both retires many new cyclists and makes roadies a growing minority in some areas of the country.

How do you get a growing minority?

 

[StuAff]

I ride with people who use all kinds of wide cassette ratios. It looks like terribly hard work.

Well, climbing the Beacon with 39x21 looks like terribly hard work to me.....

 

[dellzeqq]

Well, climbing the Beacon with 39x21 looks like terribly hard work to me.....

it is, but if I was on my hybrid, which has 48/38/28 12/13/14//15/16/17/18/19/21 it would be easy work. And I would have gained from a smooth (if slow) ride all the way down from London.

As for Albion's point - most gear changers will allow you to go down two or three sprockets in one movement. So, in the unlikely event that you get it wrong, or if there is a sudden change in gradient, you could just zip from (say) 38/15 to 38/18. And take this from a man with only one knee.........

the OP has a triple and 13/25 on the back. A triple (possibly a 50/40/30) with a ten-speed 13/26 would still give him or her a smooth ride, and a bit more top end which is handy for a road bike

 

[ColinJ]

How do you get a growing minority?

Go from 1% of a population to 2%?

 

[albion]

How do you get a growing minority?

Obviously it's when you get(to understand) prose.

I must remember to dot the i's and cross my T's though maybe roadies are growing more defensive these days.

 

[benb]

Go from 1% of a population to 2%?

Yes, that's true. I don't think that's what albion was implying though.

 

[benb]

Obviously it's when you get(to understand) prose.

I must remember to dot the i's and cross my T's though maybe roadies are growing more defensive these days.

Defensive? How dare you, what do you mean


Anyway, I'm not a roadie (well, not only a roadie)

 

[postman]

Triple.It's nice to know you can use it if you need it.My mate has a Boardman with a compact.We operate around York Otley Knaresborough Bolton Abbey Burnsall so you are getting some idea of the terrain.He recently stated at 67 he wishes he got a triple.