Single Chainring Road Bike

fcon

Just wondering has anyone converted their road bike to run a MTB style 1x10 or 1x11 groupset? I've seen SRAM are planning to release two single chainring groupsets later this year. I suppose it would lead to bigger gaps between the gears on the cassette but I don't see that as a dealbreaker. You'd probably benefit from having to spin a higher cadence than you're used to now and again or some overgear work pushing a harder gear. A 10-42T cassette off a mountain bike with a 48T chainring gives about the same range as a 12-28T with a compact. You're not losing that many ratio's anyway as you'll never have the chain on the bigger sprockets and the big chainring and vice-versa. I may be biased as I hate my front mech. It never operates smoothly and often requires a tap of my heel to go into the little ring. It means that any momentum you did have going up the hill is totally lost!

OldBean

fcon wrote: »

Just wondering has anyone converted their road bike to run a MTB style 1x10 or 1x11 groupset? I've seen SRAM are planning to release two single chainring groupsets later this year. I suppose it would lead to bigger gaps between the gears on the cassette but I don't see that as a dealbreaker. You'd probably benefit from having to spin a higher cadence than you're used to now and again or some overgear work pushing a harder gear. A 10-42T cassette off a mountain bike with a 48T chainring gives about the same range as a 12-28T with a compact. You're not losing that many ratio's anyway as you'll never have the chain on the bigger sprockets and the big chainring and vice-versa. I may be biased as I hate my front mech. It never operates smoothly and often requires a tap of my heel to go into the little ring. It means that any momentum you did have going up the hill is totally lost!

Mate of mine is running a 1x10 on his road/commuter. He loves it. He has a decent enough decent and climb too.

If I got a new road bike in the morning, I'd be tempted.

godtabh

Probably appropriate for criterium races or flat roads. Probably not much use any where that goes up and down ,GCN had a good video on the SRAM stuff recently

colm_gti

SRAM have a 1x road groupset. Be grand for crits or TTs.

Sure most roadies on a compact probably barely ever drop down from the 50t.

Alek

Probably not much use any where that goes up and down

I can (relatively painlessly) climb up to ~8% on 46 + 12/27 and spin out at approx 55kph... I guess most climbs in Wicklow should be fine on 44 + 11/32.

[edit]

Just checked, 46/34 + 12/27 has the same gear range as 42t + 11/34. Gaps must be awful, but hey, its just a matter of getting used to

smacl

The Genesis CDA 20 is a 1x10 with 42 up front and 11/36 at the back, giving a low gear ration of 1.17, which is the same as 34/29 on a compact.

Leroy42

There is the issue of the gaps, although not a deal breaker, I certainly don't see any advantage to moving to a single when the double gives you more. Why would you limit yourself?

This single seems to be an answer to a question nobody is asking. Apart from city commuters, most cyclists don't exactly 'struggle' with a double at the front. It is not a massive weight saving, the front derailleur doesn't take much maintenance and it's not exactly rocket science. Ture that many people don't need the 20 gears the double gives them and some gear overlap, but why would you even think about limiting the low and high end, with a single you need to choose one or else go with large gaps.

THE GCN video sums it up. Nothing wrong with the single, but kinda pointless really.

Lumen

Just fix your front mech. It's shouldn't need to be kicked.

Massive gaps are more annoying than front shifting.

edit: I'm currently running an 11-32 11sp cassette and the 14-16 gap (14%) is really annoying.

11-12-13-14-16-18-20-22-25-28-32

The 11sp SRAM 10-42 is

10-12-14-16-18-21-24-28-32-36-42

That's a 20% gap at the top end.

Alek

but why would you even think about limiting the low and high end, with a single you need to choose one or else go with large gaps.

Same kind of question as why are people limiting themselves to singlespeed / hardtails / flat pedals / etc. when there are better options available...

I was contemplating 1x10 myself, for simplicity - I like tight gaps too much though :P

Leroy42

Alek wrote: »

Same kind of question as why are people limiting themselves to singlespeed / hardtails / flat pedals / etc. when there are better options available...

I was contemplating 1x10 myself, for simplicity - I like tight gaps too much though :P

Not really the same. Flat pedal for eg are because people don't want the cleats, riding off road etc. I can see the point in that.

I see no advantage to this. The only selling point seems to be that you have no front derailleur to worry about. Is that really an issue? Are we faced with cyclists struggling to operate a front derailleur?

I can see it works, but unless it is significantly cheaper than the doubles currently sold then I fail to see the point.

As Lumen points out, to end up with the same spread (or as close as possible) requires very large gaps. The technology is there and proven for doubles and is pretty bullet proof, why are we going backwards and limiting the possibilites.

Seems to me that Sram realise that the era of increasing the number of gears is ending and so need another selling point to keep sales going. Nothing wrong in that, but still pointless.

colm_gti

I can see the benefit on a CX or MTB where its one less thing to get jammed with mud, but I agree, pointless on a road bike

Brian?

It's a horrible idea, the gappiness is horrific.

Alek

I used to ride 8sp 11-34 with much larger gaps than 10sp version. I never found this a problem, commuting, climbing in Wicklow, riding Audax 200, also occasionally in a group.

After I've switched to 10sp 12-27 I've noticed improvement, but not a ground-breaking one.

But then, I'm not road racing.


And honestly I don't like front shifting. Its awkward and a biatch to set up. I'd rather have full range of cassette gears with no annoying chain rub to think of.

smacl

Lumen wrote: »

Massive gaps are more annoying than front shifting.

I wonder how long before we see CVT bicycles in production. No gear changes, no gaps, just set your preferred cadence and power output

Alek

smacl wrote: »

I wonder how long before we see CVT bicycles in production. No gear changes, no gaps, just set your preferred cadence and power output

With an efficency about 97%

Yeah, yeah. :cool:

Brian?

Alek wrote: »

I used to ride 8sp 11-34 with much larger gaps than 10sp version. I never found this a problem, commuting, climbing in Wicklow, riding Audax 200, also occasionally in a group.

After I've switched to 10sp 12-27 I've noticed improvement, but not a ground-breaking one.

But then, I'm not road racing.


And honestly I don't like front shifting. Its awkward and a biatch to set up. I'd rather have full range of cassette gears with no annoying chain rub to think of.

Front derailleur takes about 40 seconds to set up: lowest gear, low limit screw set, set cable tension, shift up to highest gear, high limit screw set. Done.

Leroy42

smacl wrote: »

I wonder how long before we see CVT bicycles in production. No gear changes, no gaps, just set your preferred cadence and power output

That will never take off with Boardies.

Jebus, we give out a pie-plates imagine having that on the back wheel:p

Alek

Front derailleur takes about 40 seconds to set up: lowest gear, low limit screw set, set cable tension, shift up to highest gear, high limit screw set. Done.

Perfect in theory. I have built a few bikes from scratch in my life and there was always something wonky with FD - either this or that - that made me tinker with the bloody thing for hours.

Brian?

Alek wrote: »

Perfect in theory. I have built a few bikes from scratch in my life and there was always something wonky with FD - either this or that - that made me tinker with the bloody thing for hours.

I empathise, without fully understanding your pain.

I've sorted out a few mates front derailleurs because they've had issues. Once I showed them the above method all the trouble was over.

Alek

I empathise, without fully understanding your pain.

Brian, you should be a diplomat

smacl

Alek wrote: »

Perfect in theory. I have built a few bikes from scratch in my life and there was always something wonky with FD - either this or that - that made me tinker with the bloody thing for hours.

FD on my own bike also needs regular adjustment, albeit it is a triple. Outside of limit screws and cable tension, how well the FD works is also dependant on height above big ring and rotation where tiny changes have big effects. Going for a double on the new bike, but was briefly considering a Rohloff.

fcon

How difficult would it be to achieve? Would a MTB derailleur work with an 11 speed Road bike STI lever? Would you require a custom made wheel to fit a specific hub for the MTB cassette? Would the 11 speed MTB hub fit in a 10 speed road bike drop-outs Would you be able to get a derailleur hanger to suit? I assume a track crankset with a wide narrow chainring as long as the BCD was the same would be the ideal option?

Alek

How difficult would it be to achieve?

Just remove one of the chainrings, FD and the cable. Hey presto!

(the chain angle should still be fine, although you can use some spacers to get the chainline perfectly centered)

muckwarrior

colm_gti wrote: »

I can see the benefit on a CX or MTB where its one less thing to get jammed with mud, but I agree, pointless on a road bike

Another reason it's popular with mountain bikers is that (in combination with one or two other things) you're much less likely to drop a chain.

Mr. Grieves

muckwarrior wrote: »

Another reason it's popular with mountain bikers is that (in combination with one or two other things) you're much less likely to drop a chain.

This is the reason I've a single ring on the CX bike - one less thing to go wrong and there's also the fact that you can't really shift a front derailleur under power so you have to be careful about when you do it. So for racing, a single ring is great.

Having said that, I've done plenty of road spins on that bike with a 39 and a 11-28 cassette on the back. Never missed the extra gears. Unless you want to keep pushing on descents over 50 km/h, you don't really need the extra gears.

I haven't tried a narrow-wide ring but I'm planning on getting one. Right now the FD is still there as a kind of chainguide.