What cog combination is ideal for a road bike?

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mustang1

Legendary Member
Location
London, UK
See, a while ago the lowest gear (biggest cog) was 25. Then 27, 28, 30. Then 32 and oh lordy a 34. The other day i was watching a video and the guy had a 38! I had no idea I don't even know if that's a road cassette or did the guy stick on an mtb cassette to his road bike.

It's a bit like when CD players came out for PCs (remember, they used to call them "multimedia PCs" - what a tosh that was and I'm not even talking about Toshiba). Now where was i? Oh yes... so those CD players started off as single speed, then 2x, then triple speed. A year later 4x, the following year 6x, and finally 8x. People kept upgrading their CD players every couple of years (or did they?). Then 10x, 12x, 14x, 16x, 20x. Around about this time, people just stopped giving a crap. If those manufacturers wanted to go from single speed to 2x, and then straight to 20x, they could have. But oh no, the marketing people stopped the engineers from fulfilling their speed demons.

"If we give those dumbasses 20X right away, what the heck are we going to sell them for the next several years? We have to increase the speed of those CD drives slowly, over time, and get those consumers buying stuff every fewe years, we have to elongate the process".

And that's what I think of bike cassettes. A slow trickle. I know SRAM have a 50, but that's because they need ot use it with a single chainring (they never were good at shifting the front derailleur but that's whole different marketing scam - less is more and all that crap. So anyway, when we have double chainrings and the rear cassette grows to be as big as a 700C wheel, then they'll start over and that's why people say "history repeats itself". But by then, there will be a new breed of cyclists on the block and they wouldn't have gone through all those dinner plate size cassettes so everything will be new to them.

And so it goes.

Oh, and for another topic, don't even get me started on a little "hi fi system" the size of an big iPad that can pump out 1000W. It probably starts distorting at 50W and goes down hill from there. OMG now you got me going on front-loaded volume controls, ya know where you turn the knob quarter way and you already have half the volume so the punter thinks "oh wow i only turned it quarter and it's so loud, I've got another 75% to go". I really outta shut up now but I hope I gave some insight about cassettes. :wacko:

Ps: you might see me frequently on that "things that annoy you" thread.... :music:
 

freiston

Veteran
Location
Coventry
See, a while ago the lowest gear (biggest cog) was 25. Then 27, 28, 30. Then 32 and oh lordy a 34.
I had a 14-34T 5 speed Suntour freewheel back in 1981 and I'm sure they were around a good few years before that. The long cage of my Suntour VGT rear mech took care of the chain length.
 
Location
Wirral
I like/need better than 1:1 my best low gear was 24:32 (19") on a triple, latest bike had 34:42 (21") and the range was to ponderous so it is now 34:34 and a bit too high (26"). I'm planning on swapping to GRX to get 30/34 and see if 23" works for me. Or I might go all Spa chainset and stick some proper low gears on it.
 

All uphill

Still rolling along
Location
Somerset
That could come in handy... My Devon bike has a 42/42 bottom gear, and I managed to find a couple of hills that I couldn't quite get up on that! :okay:
I know that feeling!

I hope to be able to enjoy some longer rides over the border in Devon without pain and suffering.
 

ColinJ

Puzzle game procrastinator!
I know that feeling!

I hope to be able to enjoy some longer rides over the border in Devon without pain and suffering.
I'll be down again in October for my sister's birthday do. I hope to get a couple of long rides in, but that will depend on what the family have planned and how good/bad the weather is.

I won't avoid 20% climbs, but I'll do my best to avoid the 25+% ones this time! :laugh:
 

slowmotion

Quite dreadful
Location
lost somewhere
I've always been rubbish on hills and I always will be but I don't like walking up them. I don't like riding out of the saddle either. I have triple chainrings, the lowest is 28t. The biggest cog on the back is 28t too. On a lucky day I can ride up Ditchling Beacon in the saddle, but it's touch and go. I've failed more times than I've made it without grinding to a complete halt. Triples get you a lot of flexibility. Sure, they are regarded with distain by lots of people but I'm sufficiently ancient not to care about that.

50/39/28 chainrings
12-28 cassette
 

Alex321

Veteran
Location
South Wales
I've always been rubbish on hills and I always will be but I don't like walking up them. I don't like riding out of the saddle either. I have triple chainrings, the lowest is 28t. The biggest cog on the back is 28t too. On a lucky day I can ride up Ditchling Beacon in the saddle, but it's touch and go. I've failed more times than I've made it without grinding to a complete halt. Triples get you a lot of flexibility. Sure, they are regarded with distain by lots of people but I'm sufficiently ancient not to care about that.

50/39/28 chainrings
12-28 cassette

But a double with 50/34 and 11-34 on the back, which is a pretty common setup nowadays, will give you the same bottom gear, and in fact a very slightly wider range. The triple just gives a bigger overlap.
 

slowmotion

Quite dreadful
Location
lost somewhere
But a double with 50/34 and 11-34 on the back, which is a pretty common setup nowadays, will give you the same bottom gear, and in fact a very slightly wider range. The triple just gives a bigger overlap.
Absolutely. The bike in question originally came with 50/39/30 chainrings and 12-28 cassette. I just bought a 28t replacement chainring from Spa Cycles to help me with hills. I don't need 30 gears. For 95% of my riding, I grind along on the biggest chainring. It may not be efficient, it certainly isn't fast......but it suits me.
 
Location
London
I've always been rubbish on hills and I always will be but I don't like walking up them. I don't like riding out of the saddle either. I have triple chainrings, the lowest is 28t. The biggest cog on the back is 28t too. On a lucky day I can ride up Ditchling Beacon in the saddle, but it's touch and go. I've failed more times than I've made it without grinding to a complete halt. Triples get you a lot of flexibility. Sure, they are regarded with distain by lots of people but I'm sufficiently ancient not to care about that.

50/39/28 chainrings
12-28 cassette
If you are struggling that much up ditchling I would get lower gears. I used to ride with something like your set-up (maybe 25 big on the back) and used to struggle. Being a slow learner it took me a while to figure out when I first started cycling that some folk had an easier progress up hills because of their more appropriate gears.
Three of my bikes have a 22T on the front.
 
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GuyBoden

Guru
Location
Warrington
I've been avoiding riding up hills for most of my life, I live in Cheshire, so it's not really a problem.

But, currently I have a triple 22-32-42 on the front and 11-34 sprockets on the rear cassette. I need low gears to get home after a long day in the saddle when any slight incline seems like Mont Ventoux.
 
Location
London
I've been avoiding riding up hills for most of my life, I live in Cheshire, so it's not really a problem.
agree with this for sure - been riding a lot across cheshire last couple of years - have the impression that the greatest incline is probably taken care of by the Anderton boat lift.

Don't you find the top of 42 a bit low if your only bike? maybe a case for a 44T at least?
 

ColinJ

Puzzle game procrastinator!
been riding a lot across cheshire last couple of years - have the impression that the greatest incline is probably taken care of by the Anderton boat lift.
Seek, and ye shall find... :whistle:









And so on...

I got caught out by one on the B5166 between Wilmslow and Styal once. There is a descent and then a bend into some woods. I went round the bend in the big ring and ground to a sudden halt in traffic...

611471


Don't you find the top of 42 a bit low if your only bike? maybe a case for a 44T at least?
That's not bad - it gives about 43 kph (27 mph) at 90 rpm. I made do with 52/14 for years, which is a slightly lower ratio than that.
 
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