Single ring on a road bike, curious case of n-1

I don’t race on the road, just the odd sportive and social rides.

I’m seriously considering getting a nice carbon disc cx bike and having 2 sets of wheels set up, one with cx tyres and the other road.

I race cx with a single ring set up and was wondering if say a single ring crank with two sized rings, smaller for cx and larger for road is a good idea

I have often wondered the same. I think that (for me) I ride in a totally different way not he road to MTB, which would make it irritating I am used to dialling in a more or less exact cadence, and I would halve the opportunities to do that.

If you are not so sensitive to this, then I would say its a goer.

Would you really change wheels, chainring and chain then potentially re-index for each time you wanted to vary the bike set up? I know if it was me I would just never bother.

Just get a 10-42 cassette on there and a 40T upfront.

Or how about a double and an 11-32?

I use 1×11 on the road, running a slightly monumental 50t front ring as I though I had the minerals to push it. Its hard work but thats purely because I’ve gone for the wrong front ring. However not having to trim the front mech, the lack of weight and one less cable to worry about is all worth it. With a 46 I think it’d be about spot on, with the 11 speed cassette giving me a decent range.

I wouldn’t bother on a 10 speed due to too bigger gaps between gears but that’s personal preference.

I don’t race on the road, just the odd sportive and social rides.

Almost certainly a good candidate for 1x on the road then.
I’m convinced I would prefer 1x on the road for the bulk of my riding, but generally once a year i’m in the mountains in Europe so have stuck with the compact.

As I don’t really ride on the road in winter much, it wouldn’t be too much hassle to change a ring and wheels. Why the re-index?

Although I have a dedicated road bike I do just that with my Arkose in the winter. Knobbly and 38T for off-road, slick and 42T for road.

A single ring set up with the same range as a double ring will only have two fewer ratios. That might make a big difference to someone wanting to maintain a constant cadence whilst holding a wheel in a bunch, but not to me.

It would be doable, but seems limiting to me for no benefit.

You would need to size your chain and rear mech on the bigger of the two rings, would you end up with a lot of slack when running the smaller ring? (arguably when you want the least slack i.e. offroad?).

Why the re-index?

I guess to accommodate for any difference in cassette position between wheels? Your disc could end up in a different position too, if the bike has disc brakes that is.

With 10-42 I would have thought you can just run the one wheelset and chainring.
Easy to work out the gear ratios/gear inches you actually (not theoretically) use eg at
http://www.sheldonbrown.com/gear-calc.html
…. then decide what front ring suits best, or not, if that is the case.Can always just use those gears on the current bike first to check.

I really like the simplicity of 1*11 and have just started Cx (I’m worse than hopeless), but I’m a spinner on the road so use 38 front chainring for both. I never miss the bigger gears (but I don’t ride chain gangs etc, just with mates). The steps wouldn’t suit everyone but at least you can know if the range is right beforehand.

38 front ring for road use on a 1*11 😯

I really like the simplicity of 1*11

I don’t get this, it is hardly like 2×11 is complex.

You would need to size your chain and rear mech on the bigger of the two rings, would you end up with a lot of slack when running the smaller ring? (arguably when you want the least slack i.e. offroad?).

You size for the larger chainring. When using the smaller chainring it’s no worse than using the larger chainring and not being in the largest cog in the cassette.

Why the re-index?
I guess to accommodate for any difference in cassette position between wheels? Your disc could end up in a different position too, if the bike has disc brakes that is.

The wheels will both be 135mm, the cassettes will be the same width, and the rotors in the same place. There’s no need to reindex anything.

I have 1×11 on the CX bike and vary the ring, 38T for climbing courses, 40T for flat (bought a few cheap from SS to try and happy to swap ’em around, fits in with my geeky obsessiveness, like changing tyre pressure by 1psi).

Wouldn’t want it on a road bike as you either have a more limited ultimate range, or gaps that are too large. The benefit of going from 10 to 11spd wasn’t a bigger overall range, it was closer gears meaning you can seamlessly maintain your cadence as speed/gradient/conditions change.

Have a look on GCN Youtube, one of their US contributors (Neal Rogers?) does an extended test, it’s a pretty qualified endorsement and he admits to struggling at either end depending on chainring size.

A racer is more likely to be able to manage 1×11 than a recreational rider by being able to vary their cadence more dramatically.

38 front ring for road use on a 1*11

I really like the simplicity of 1*11
I don’t get this, it is hardly like 2×11 is complex.

I know sounds shocking. But it only gives 1 gear less than 50-12 on my Synapse (105 gear inches vs 112) which I don’t miss, even on group rides.
I was always fiddling for the best gear for my cadence, getting it just right. Now it is easier..up or down with a decent enough gap to know about it. Not physically much easier, I grant you… more philosophically (retreats shamefully).

You can see why I’m hopeless at Cx now. Although I enjoy the view.

I don’t get this, it is hardly like 2×11 is complex.

No, but it can be a pain when your average cruising speed is very close to the point where you need to swap rings.

The wheels will both be 135mm, the cassettes will be the same width, and the rotors in the same place. There’s no need to reindex anything.

That is the theory, however sometimes theory and reality are not the same thing sadly.

I’m running my pickenflick 1×10 as winter roadie/cx bike

11-25 cassette on road wheels and I think 11-32 on cx wheels 44t up front

Get round local chaingang(fast group) with some effort 😀

Winter roadie/off road rig by Plus one2010[/url], on Flickr

On one pickenflick by Plus one2010[/url], on Flickr

1×11 with baggy chain sounds like a non-starter for cross, chain will be off in no time. Unless one of those new sram force mechs really does the business, then you’d need two chains.

Mechanical problems in a cross race are a total ballache, whereas having stuff ‘close enough’ on a social road ride is no big deal. So the drivetrain would need to be bang on for the cross, first and foremost.

The disk rotors on different hubs can be out by a fraction, which given the close tolerances of the caliper means a re-positioning – I have this on my race wheels and everyday cross wheels. It’s not a big deal, just one more thing to set-up.

I don’t get this, it is hardly like 2×11 is complex.

You’re right, it doesn’t seem comnplex because we’re all used to it. But 1x is simpler.

Imagine a manual car that didn’t have a single gearbox. Instead of six speeds it had four, but with a dual ratio transfer box. You’d start in first and low range, then second, then third, but then for the next ratio you’d have to change to high range and back down to second, then third again, then fourth. That’s what we do with 2x gearing. It’s just that we accept it as the norm.

+1 for

That is the theory, however sometimes theory and reality are not the same thing sadly.

and

The disk rotors on different hubs can be out by a fraction, which given the close tolerances of the caliper means a re-positioning

Munqe chick has a set of DT Swiss and a set of Novatec hubbed wheels and they swap perfectly. I have a set of Kinesis and a couple of OE sets, and they don’t. Disc and/or cassette can be out by just enough to stop it working properly.

Plus One, did your roadie mates make you put Voodoo stickers on your Pickenflick before you were allowed out with them?!

That is the theory, however sometimes theory and reality are not the same thing sadly.

Fair point. If someone does need to reindex though I’d suggest the dishing is slightly out on one of their two wheels.

I race cx with a single ring set up and was wondering if say a single ring crank with two sized rings, smaller for cx and larger for road is a good idea

If it is not too hilly, I would just use a different cassette; say an 11-23 for the road and a 12-32 for cross. Choose your front ring carefully. I’ve gone for a 38T on the front, and 38×11 is 3.45:1. For reference, I ride fixed on 3:1 (42×14), and this is a decent gear for medium fast club rides. It is not high enough for the fast group, but I can average just over 20 mph.

You will not be changing chainrings, you just won’t! Select decent cassettes instead, and go for it. For a sportive, it will be absolutely fine.

EDIT: Most compact groupsets are 1×11 with a bailout option anyway.

I started singlespeed 48:16 when I built up the roadcrosscommuter type thing.

Slapped a 10 speed cassette on for a SDW ride, left it on, got another wheelset, swapped back and forth, depending. SLX/ open pros with commuting tyres, Stans Alpha wheelset with either Thunder Burts or GP4S for long rides at weekends. No issues indexing. Or disc spacing, once I’d done a little fettling with the rotors on the Stan’s set. I’ve never been a serious roadie, so the gaps don’t bother me, worked fine for me on plenty of long road rides.

Dropped to 38T for Cross racing, left it there. Don’t really miss the 48T on the road, more usable off road.

Edit: I like the different cassettes idea. I’d not really thought about that. sounds obvious now, though!

Running 2×11 isn’t necessarily about increasing the gear range, but allowing tighter gaps between gears. Also running a 1×11 on small cogs and chainrings increases wear, not that SRAM will mind that.

There have been a few high profile chain drops in top level cyclocross this year, so 1×11 has created new problems while solving some others.

Fair point. If someone does need to reindex though I’d suggest the dishing is slightly out on one of their two wheels.

How on earth can the position of the rim have any bearing whatsoever on the position of the cassette & disc rotor?

You’re absolutely right. Ignore my last post!

I run 1×11 10-42 and 40T on winter bike

Its the same top gear as my summer road bike….

1 x 10, 11-36 with 38T front for me on the commuting bike. I do a bit of offroad commuting during summer and it works well for that type of mixed riding.

1×10 on the commuter
38t oval
11-32 out back

I went 1×11 on my XC mtb and hated it. I had the range, but constantly felt I was in the wrong gear in the middle of the cassette.

I think the gaps would be even more noticable on the road, especially if you spin up the hills like me.

I went 1×11 on my XC mtb and hated it. I had the range, but constantly felt I was in the wrong gear in the middle of the cassette.

I’ve noticed that on my 1×11 not quite hated it but preferred the wide range of the Alfine 8.

Cheers, Steve

Just messaged you on fbook Steve

Anyway… My 2p…

1x is the way forward on both MTB & CX for sure. Even only if 1×10, but 1×11 and now 1×12 are awesome and provide no reason to go back to more than 1 chainring offroad.

On road however, 1x is infuriating. Constantly searching for gears that don’t exist (at either end of the cassette, and inbetween ratios on the cassette you’re using) and the inability to “press on” when required. I don’t race, but sometimes our group ride will pick up the pace, and 1x was totally ridiculous for trying to keep in the group!

Went back to 2 rings and super happy I did. Front derailleurs don’t get such a hard time on the road anyway, so they shift better than on MTB’s anyway, and then you get to Di2 or Sram eTap… 22 fully useable gears with no issues! No contest, I’m sticking with 2 up front on road.

I have a slightly different take on things.
I run 1×11 on my cervelo s3 – it’s a racy bike and I’m not running out of gears up or down the range. This is probably as I Taylor the cassette for the locations I ride. Generally it’s pretty undulating and I found my average speeds increased when I converted to this format.

I also have a synapse di2 which is ok but find the front shifting annoying as I’m forever on the cusp of either ring.

Anyway, I’m happy and that all that matters.

Alot will depend on where you ride and how much you ride.

But even then, it’s a daft idea.

Look at the chain line when in the top and bottom sprockets (that you’ll be having to use alot of aswell!) Truly awful. It creates extra wear along with inefficiency in the drivetrain. All that training you’ve done; there goes your extra watts.

If it looks wrong, it usually is.

1×11 here 11 x 40 cassette with a 42 single up front the only place I lose out is on long steep descents, love it 🙂 do most of my riding around Devon and somerset so quite hilly !

All that training you’ve done; there goes your extra watts.

Lolz 😆

Look at the chain line when in the top and bottom sprockets (that you’ll be having to use alot of aswell!) Truly awful. It creates extra wear along with inefficiency in the drivetrain. All that training you’ve done; there goes your extra watts.

Depends on the bike. My cervelo is bbright so going single corrects the abomination they created. I have a really nice chainline cheers 🙂

Urgh 11-40 cassettes gaps so big between gear you you fall in them.

Was bad enough o. The hire road bike in tenerife when the bike had 11-36 to help granny’s up the the climb to Teide I think.

Constantly looking for the correct gear to maintain my leg speed ….and it wasnt there.

I wonder if it’s to do with length of ride ? I couldn’t put up with the gaps on an all day ride but similarly if im only out for an hour I use my ss and I’m in the wrong gear the whole ride 🙂

1×9 here on my road bike.
Was 53-39 running 12-23 cassette, now running 44 ring and a 12_28 cassette.
Suits me fine.

How about two rings up front, and a shifter. But ride with a great big mitten on your left hand so you’re not tempted to use it.