Why would a triple have a 11-32 cassette?

quozl · 15-06-2013 10:30PM #1

Just a question from curiousity - why would a bike with a 48/36/26 chainset have a 11-32 rear cassette?

Like on this bike?

http://www.trekbikes.com/us/en/bikes/town/fitness/fx/7_3_fx/

Surely all that does is give you massive overlap on the gears, big gear jumps and the ability to climb absurd hills that you'd likely never climb on a bike like that?

An 11-26 would give you the same top speed, a 1:1 granny-gear and much smaller gear jumps (especially as it's only 8 speed in this particular bikes case).

Can anyone explain the reasoning behind the other? I get why you might want such a wide cassette on a compact but not with a triple, I'm new to bicycle gearing and I'm wondering if I'm missing something obvious here.

IM0 · 15-06-2013 11:46PM

you are, some people need very light gears for steep climbs, its an ability thing.

Captain Havoc · 16-06-2013 05:29PM

Not everyone who rides a bike is superbly fit. If you cycle a couple of kms to work but have to cycle up a very steep hill, I'm sure the gears would be useful.

Mycroft H · 16-06-2013 05:46PM

touring load. panniers and such like.

feck sake lads · 16-06-2013 06:09PM

on a loaded touring bike going up hill you will be glad of them .:cool:

cdaly_ · 16-06-2013 07:50PM

On a bike loaded with only me I'm glad of them...

Darkglasses · 16-06-2013 08:01PM

My old hybrid has gearing like that, I think I did use the lowest gear a couple of times going uphill into the wind on my evening commute. Soon grew out of it.

I currently use the lowest gear when I take that bike off-road.

doozerie · 16-06-2013 09:19PM

I have a triple on my MTB (22/32/42), fitted with slicks. I use it on the road all of the time so I have a narrow range cassette on it (11-23), and I never use the granny ring. However, on holiday recently in Yorkshire I rode up a 17% gradient while towing a child trailer and I was glad of my 22-23 gearing and that's only slightly higher a gear than 26-32 - in fact I might have gone lower again if I'd had another gear available. And certainly in that part of the world a 17% gradient is common as muck and there are plenty of 20%, 25%, and even the odd 33%, gradients knocking around.

So as per the previous posts your choice of gearing really depends on a variety of things including the nature of your riding (touring, towing, etc.), whether you like to spin or grind (and you can still find yourself grinding a bit even in very low gears, under certain circumstances), age, physical constraints, your local terrain, etc. Such low gearing certainly isn't for everyone but I could see why there is a demand for it.

enas · 16-06-2013 10:20PM

Actually, I'm wondering the opposite. I get that on this type of bike, you need a low lowest gear. But what about the smallest sprockets, isn't the 11 sprocket a bit low for this bike? I mean, with one calculator I used online, 48 front with 11 sprocket at 90rpm pedalling gives us over 50 km/h, close to 60km/h at 100rpm. How often would anyone ride at those speeds on such a bike? I'd rather go with smaller gear jumps and sacrifice the highest gear, especially if I was the kind of persons who needs very low gears. I agree that the gearing is a bit strange with that bike...

smacl · 16-06-2013 10:36PM

enas wrote: »

Actually, I'm wondering the opposite. I get that on this type of bike, you need a low lowest gear. But what about the smallest sprockets, isn't the 11 sprocket a bit low for this bike? I mean, with one calculator I used online, 48 front with 11 sprocket at 90rpm pedalling gives us over 50 km/h, close to 60km/h at 100rpm. How often would anyone ride at those speeds on such a bike? I'd rather go with smaller gear jumps and sacrifice the highest gear, especially if I was the kind of persons who needs very low gears. I agree that the gearing is a bit strange with that bike...

I rented a bike last year cycling from to Dingle from Tralee over the Connor pass with a 14kg backpack. The super low gears were grand for the climb, but the bike was totally undergeared on the flat (46/13). Extra weight only makes a difference on a incline, I would've loved and 11 or 12 in the cassette.

Darkglasses · 17-06-2013 12:31AM

enas wrote: »

Actually, I'm wondering the opposite. I get that on this type of bike, you need a low lowest gear. But what about the smallest sprockets, isn't the 11 sprocket a bit low for this bike? I mean, with one calculator I used online, 48 front with 11 sprocket at 90rpm pedalling gives us over 50 km/h, close to 60km/h at 100rpm. How often would anyone ride at those speeds on such a bike? I'd rather go with smaller gear jumps and sacrifice the highest gear, especially if I was the kind of persons who needs very low gears. I agree that the gearing is a bit strange with that bike...

Now there's a good question, in my opinion. Most beginners aren't going to touch the pedals on the way down a climb, unlike smacl above. I very rarely put my triple-equipped hybrid in the top gear, and mainly just to challenge myself.

Suppose you have to put something on the sprocket.

Brian? · 17-06-2013 04:52AM

Darkglasses wrote: »

Now there's a good question, in my opinion. Most beginners aren't going to touch the pedals on the way down a climb, unlike smacl above. I very rarely put my triple-equipped hybrid in the top gear, and mainly just to challenge myself.

Suppose you have to put something on the sprocket.

I have a compact 50/34 on my bike. Over 40kph I reckon I'll spin out a 50x11 handy enough. I'm glad of the 34-25 going up hill though

Why would a triple have a 11-32 cassette?

Comments