Please help me understand gears

markiegrim

I am a Newbie looking to buy a road bike ca. £750 max

Today I test rode a 2012 Cannondale Synapse Sora. It had 9 gears and a tripple at the front (excuse lack of correct terminology!) = 27 speed

Seems a lot compared to most road bikes which seem to have a double up front (say, 18 speed). Is there any benefit of the 27 v 18 speed? I'm not concerned so long as the highest and lowest gears on a 18 speed set is basically the same (ratio?) as the 27 speed

If anyone understands this garbled nonsense and can advise, would be most grateful

Thanks

macroadie

9 gears is plenty if you are beginer. I don't see any benefit to understand this numbers so long as the bike fits you. Remember it's not the bike but the engine.

gethinceri

Smallest round toothy thing on the front combined with biggest toothy thing on the back is lowest, biggest round toothy thing on the front combined with smallest toothy thing on back is highest.
Or click here:
http://sheldonbrown.com/gears/

MrChuck

You might find the triple has a lower bottom gear than a double, which means you can get up steep hills easier- IMO the higher number of combinations is neither here nor there for road bikes.

Basically road bikes have either a standard double, a compact double, or a triple. For non-racers a compact double is probably the best bet- not as low a bottom gear as a triple but should be low enough unless you live somewhere super hilly. Don't be put off by the lower top-end gearing, they're still plenty fast enough!

ForumNewbie

There is nothing wrong with a triple chainring at the front. The smallest of the front rings will probably have 30 teeth, which combined with the largest sprockets at the back, will get you up most of the steepest hills. A compact with 2 chainrings at the front is okay as well but the smallest ring usually has 34 teeth. I have bikes with both, and the triple has at least a gear lower than the compact - i.e. better for really steep hills. Some 'roadies' look down on triples, but I quite like the variation they give - like when you drop to the middle ring (39 or 42 teeth) its not as big a drop down in gears as with the compact.

Just avoid standard doubles as the smallest of the two front chainrings usually has 39 teeth meaning you will struggle on steep hills.

Crank spank

Benefit of the "27" is that if you live in a particularly hilly area you can change to the granny ring (smallest sprocket on the front) and spin those legs up.

I however, live in the flattest part of the uk (east anglia) and never use the granny ring. I should have bought a double :-(

navrig

Call my wife, she will be explain it to you or at least given how many times I've explained it to her she should be able to tell you.

markiegrim

Thanks all - great stuff

sparklehedgehog

Navrig wrote:

Call my wife, she will be explain it to you or at least given how many times I've explained it to her she should be able to tell you.

I feel your pain brother.

cesco

Crank spank wrote:

I however, live in the flattest part of the uk (east anglia) and never use the granny ring. I should have bought a double :-(

This entire sentence: same for me. It seemed nice when I bought it, guess it was just the novelty for me, as I had never heard of it before getting into road bikes again. I can't stand it now: don't like the looks and shifting seems rougher.

That said, I must admit that all the gearing options were a bit overwhelming on my first couple of rides, coming from a 12 speed bike to a 27 speed one. Yep, I had a 2x6, and I have to disagree with the "don't get a standard double" advice. I have always found my old 52-42 nearly flawless. Especially considering it was only a Simplex front mech working a Biopace chainring. Then again, I must say that I don't have any proper climbing experience.

CiB

ForumNewbie wrote:

Just avoid standard doubles as the smallest of the two front chainrings usually has 39 teeth meaning you will struggle on steep hills.

Disagree. Assuming you don't live in The Peak or Lake District 39-28 will get you up most things once you've got past the beginners phase and achieved a level of fitness, and the 53-11 at the other end will allow you sit up the back end of a truck on a rural clearway if the fancy takes you. I'd recommend a standard (39/53) with a 11-28 cassette on the basis that you want a bike that you can grow with, rather than buying a beginners bike and riding a beginners bike until you decide it's time to move on to something better, by which time you'll have taught yourself to ride a beginners bike and will face a big leap to real gear ratios. Struggle for a short while and get used to it. It's not that hard.

Runtothehills

CiB wrote:

ForumNewbie wrote:

Just avoid standard doubles as the smallest of the two front chainrings usually has 39 teeth meaning you will struggle on steep hills.

Disagree. Assuming you don't live in The Peak or Lake District 39-28 will get you up most things once you've got past the beginners phase and achieved a level of fitness, and the 53-11 at the other end will allow you sit up the back end of a truck on a rural clearway if the fancy takes you. I'd recommend a standard (39/53) with a 11-28 cassette on the basis that you want a bike that you can grow with, rather than buying a beginners bike and riding a beginners bike until you decide it's time to move on to something better, by which time you'll have taught yourself to ride a beginners bike and will face a big leap to real gear ratios. Struggle for a short while and get used to it. It's not that hard.

I find that with a 50-12 I spin out somewhere above 40mph, with a 50-11 that would increase to above 44mph which is more than enough for most people, especially if you live somewhere flat.

On the other hand the 34-27 at the low end is very useful as I like steep slopes (1 in 4 or greater) whenever I can find them.

A compact does not mean a beginners bike and a double is not better, particually if you want to go uphill at any point.

slowbike

Gears really does depend on your current fitness and where you want to ride.
My first road bike was a 39/52 with 26-13 cassette ... on the short 8-9% gradients around here I could grind my way up. Even up to 15% on a longer climb, but it was a struggle and I'd only ride it occasionally. On shorter hills it's mostly down to the strength in your legs ....

Schoie81

If it helps, i'm pretty new to road biking and I DO live in the Peak District / High Peak. I have a 50/34 compact with an 11/28 cassette. 34-28 gets me up 4% over 4miles (pretty easily - in fact I probably do that in 34-24 or 34-21) 8% over 1mile (now, but didn't at first), 10% over about 1/2mile and 12% over 1/4mile (just - couldn't have gone much further than 1/4mile at that gradient last time I tried that).

I don't think I'd have had much joy with a standard double around the Peak District, a triple would have made things easier, but with some effort and practice, the compact is fine for me as a beginner.

And at the other end, 50-11 is plenty fast enough for me!!

Daz555

CiB wrote:

ForumNewbie wrote:

Just avoid standard doubles as the smallest of the two front chainrings usually has 39 teeth meaning you will struggle on steep hills.

Disagree. Assuming you don't live in The Peak or Lake District 39-28 will get you up most things once you've got past the beginners phase and achieved a level of fitness, and the 53-11 at the other end will allow you sit up the back end of a truck on a rural clearway if the fancy takes you. I'd recommend a standard (39/53) with a 11-28 cassette on the basis that you want a bike that you can grow with, rather than buying a beginners bike and riding a beginners bike until you decide it's time to move on to something better, by which time you'll have taught yourself to ride a beginners bike and will face a big leap to real gear ratios. Struggle for a short while and get used to it. It's not that hard.

You seem to be associating compacts with "beginners" which is frankly nonsense. Not quite sure what "real gear ratios" are.

southdownswolf

As a "beginner" I had (have) an old Raleigh with 52/42 up front. Now I am more experienced I have a 50/34.......

drlodge

southdownswolf wrote:

As a "beginner" I had (have) an old Raleigh with 52/42 up front. Now I am more experienced I have a 50/34.......

Ditto. My 34/50 - 12/27 combination is perfect for the Surrey hills and I use the lowest gear quite a lot on steep and long hills. I don't see me ever changing to a 53/39 chainset if I want to climb hills of any decent incline. The steepest climb near me is Barhatch Lane at 21% at the top, even with the 34/27 it is a challenge.

smidsy

CiB wrote:

Disagree. Assuming you don't live in The Peak or Lake District 39-28 will get you up most things once you've got past the beginners phase and achieved a level of fitness

I do not think it is that simple.

I run a compact (34/50) and a 11/28 cassette and after 18 months of cycling (including 100 milers and sunday club runs) I still find climbs where I am seriously glad of the 34/28 availability.

I live near Leicester/Derbyshire border and without the compact I would be walking - lots. I would not consider the climbs particularly difficult either - so your 39/28 idea is contrary to my experience.

drlodge

smidsy wrote:

CiB wrote:

Disagree. Assuming you don't live in The Peak or Lake District 39-28 will get you up most things once you've got past the beginners phase and achieved a level of fitness

I do not think it is that simple.

I run a compact (34/50) and a 11/28 cassette and after 18 months of cycling (including 100 milers and sunday club runs) I still find climbs where I am seriously glad of the 34/28 availability.

I live near Leicester/Derbyshire border and without the compact I would be walking - lots. I would not consider the climbs particularly difficult either - so your 39/28 idea is contrary to my experience.

Ditto, per my post above. Even on more modest inclines (Kidds Hill springs to mind which is long and "only" about 10%-12%) I would be in the bottom gear (34/27), grinding my way up. No way would my legs last that hill on a 39/27.

dnwhite88

drlodge wrote:

southdownswolf wrote:

As a "beginner" I had (have) an old Raleigh with 52/42 up front. Now I am more experienced I have a 50/34.......

Ditto. My 34/50 - 12/27 combination is perfect for the Surrey hills and I use the lowest gear quite a lot on steep and long hills. I don't see me ever changing to a 53/39 chainset if I want to climb hills of any decent incline. The steepest climb near me is Barhatch Lane at 21% at the top, even with the 34/27 it is a challenge.

I run a compact with 11-28 and only really need the 28 on barhatch and climbs like the mount. Am going to the Dolomites in sept so will probably be glad of it there too!

chrisaonabike

smidsy wrote:

CiB wrote:

Disagree. Assuming you don't live in The Peak or Lake District 39-28 will get you up most things once you've got past the beginners phase and achieved a level of fitness

I do not think it is that simple.

I run a compact (34/50) and a 11/28 cassette and after 18 months of cycling (including 100 milers and sunday club runs) I still find climbs where I am seriously glad of the 34/28 availability.

I agree. That was exactly the sort of at unhelpful post I was referring to elsewhere where a strong rider has forgotten what it's like to be not so strong.

Posters of such things invariably say 'you' when they mean 'I'.

I ride a lot in Surrey, and although I'm a lot stronger than I was when I started this time last year, I'm very glad of my 50/34 12-30 thanks very much. I get knee pain if I grind at low cadence, so the idea of fcuking up my knees getting up the hills on a 39 doesn't sound that clever to me.

CiB

ChrisAOnABike wrote:

smidsy wrote:

CiB wrote:

Disagree. Assuming you don't live in The Peak or Lake District 39-28 will get you up most things once you've got past the beginners phase and achieved a level of fitness

I do not think it is that simple.

I run a compact (34/50) and a 11/28 cassette and after 18 months of cycling (including 100 milers and sunday club runs) I still find climbs where I am seriously glad of the 34/28 availability.

I agree. That was exactly the sort of at unhelpful post I was referring to elsewhere where a strong rider has forgotten what it's like to be not so strong.

Posters of such things invariably say 'you' when they mean 'I'.

I ride a lot in Surrey, and although I'm a lot stronger than I was when I started this time last year, I'm very glad of my 50/34 12-30 thanks very much. I get knee pain if I grind at low cadence, so the idea of fcuking up my knees getting up the hills on a 39 doesn't sound that clever to me.

Still going on about it then? My post was intended to make two points, one that what we used to call granny rings seems to have morphed into the beguilingly named compact to give them some kind of legitimacy, and that part of cycling is becoming better at it, going further, faster etc etc. It is a long time since I was a beginner struggling but that's what I did anyway and got the hang of it, so these days a 100 mile trek that takes in the flatlands of Ashbourne, Chapel en le Frith, Glossop, Blackstone Edge etc is doable on a 39/25 (granted some of them are bit of a fight but that's part of it), and now that I've dropped to an 11-28 there's a bit more leeway. Having just bought an off-road bike with stupidly low gears I know which I prefer. You carry on though. Sorry for daring to take an alternative position on these obviously sensitive matters and for even daring to suggest that there's some satisfaction to be gained by not opting for the lcd approach. Carry on.

Runtothehills

On the other hand advantages of a compact:
1) Can spin up most hills which is more efficient and better for the knees
2) Slightly lighter than a double
3) Don't need to mess about with changing your gearing so much when you find a real hill

Advantages of a double:
1) Ability to pedal at more than 45 mph - great if you're Mark Cavendish, not so useful if you're not interested in contesting sprints.
2) Makes you feel better as you run 'proper gears'

ForumNewbie

Let's not forget the original poster was looking at a bike with a triple chainset, but also asked about doubles. In my earlier post I explained the difference between a double and compact, and pointed out that if he did consider 2 rings at the front he would be best to consider a compact (rather than a standard double) against a triple. If he knowingly goes for a standard double, but is fit and strong and knows it will be tough in the hills (or lives in a very flat part of the country) that is fine - it's his choice.

However if that is not the case, I think he should be weighing up the benefits of triple v compact. I have both and have no qualms about riding with a triple and going into the granny ring on very steep hills if the need arises. Also when you drop to the middle ring on the triple, I'm not spinning and having to move up gears at the back immediately like I have to do withe the compact sometimes. So a triple is worth considering by the OP.

markhewitt1978

CiB wrote:

Disagree. Assuming you don't live in The Peak or Lake District 39-28 will get you up most things once you've got past the beginners phase and achieved a level of fitness, and the 53-11 at the other end will allow you sit up the back end of a truck on a rural clearway if the fancy takes you. I'd recommend a standard (39/53) with a 11-28 cassette on the basis that you want a bike that you can grow with, rather than buying a beginners bike and riding a beginners bike until you decide it's time to move on to something better, by which time you'll have taught yourself to ride a beginners bike and will face a big leap to real gear ratios. Struggle for a short while and get used to it. It's not that hard.

Some of the worst advice I've ever read here.

drlodge

markhewitt1978 wrote:

CiB wrote:

Disagree. Assuming you don't live in The Peak or Lake District 39-28 will get you up most things once you've got past the beginners phase and achieved a level of fitness, and the 53-11 at the other end will allow you sit up the back end of a truck on a rural clearway if the fancy takes you. I'd recommend a standard (39/53) with a 11-28 cassette on the basis that you want a bike that you can grow with, rather than buying a beginners bike and riding a beginners bike until you decide it's time to move on to something better, by which time you'll have taught yourself to ride a beginners bike and will face a big leap to real gear ratios. Struggle for a short while and get used to it. It's not that hard.

Some of the worst advice I've ever read here.

I agree. To call a bike with a compact chainset a "beginners" bike is just rubbish. And I see no point in struggling at all, each has their own level of fitness, weight, selection of hills to get up etc so everyone has different needs. Doubt I will ever get a "proper" chainset, I'd rather stick to my beginers bike that cost oooh, only £5k.