ChucklesKY

Last year was my first year racing 'cross. Did about a half dozen races on a pretty much traditional 'cross set-up: 36/46T chainrings (130BCD) and a 12-27T cassette. Components are SRAM Apex. I found myself spending a more time in the small chainring. I'm seriously thinking of going to a 1x10 set-up for simplicity, weight savings, cool factor, etc. I think a 40T chainring would probably be the way to go. Maybe Wolf Tooth. My head is spinning on contemplating the rear. I could pretty much go immediately with a 11-28T and use my Apex RD but not sure I would have the low-end I need. I have thought about a WiFli derailleur and an 11-32T. Another option that I have just started looking at is a MTB RD like a SRAM X9. Then I could go as high as an 11-36T cassette if I needed it for something like a gravel event. The SRAM MTB Rear Derailleur "Roller Bearing Clutch" for driveline stability sounds interesting. Any advice/experience/thoughts on the rear derailleur and cassette options would be appreciated.

justin1138

I'm in the same boat as you, just doing it with a Shimano drivetrain. I swapped my double rings for a Race Face wide/narrow chainring because it was a) considerably cheaper than the other versions out there, b) and my LBS carries them. The chainring is going to get thoroughly tested tonight.

This week I'll also be getting a clutch type rear derailleur to further aid in chain retention. I wanted to keep the short cage rear derailleur on, but I thought it'd be a better idea to make sure the chain stays put. Everything I've read suggests that the combo of a wide/narrow chainring + clutch type rear derailleur should keep the chain in place.

As it sits right now, I have a 42 up front and 11-28 in the back.

fietsbob

A Chainguard disc sandwich is the traditional solution .. weight conscious? FSA has carbon fiber ones..

HOWSER

I went with the single Wolftooth (40) up front last year and a 12-28 in the rear. Was worried that it wouldn't be enough gearing at first but not once did I ever run out of gear. There may have been a time or two that I had to mash up the steepest section but it certainly worked out well.

Also, I mounted that front ring on the inside of the spider, not the outside. Seems to really help with chain drop.

Not once did I drop a chain with that setup either.

justin1138

Raced yesterday on a very bumpy, teeth rattling course. No dropped chains. The wide/narrow chainring with a 105 rear derailleur is doing the trick.

JeffS

A podium spot was never won or lost over a front derailleur.

Orion12521

Ask Katerina Nash if she would have preferred second place over third at the 2013 World Championships in Louisville. She dropped her chain coming onto the finishing stretch. Does that count? It was kind of an important race and all.

adam_mac84

I lost a regional championship (cat3) last year over 3x chain drop in 1 race (same spot each lap). Have gone to clutch derailleur now. Crazy good retention in a very bumpy race this weekend

Niloc

you know, I thought about going 1x and asked questions on this forum, well it's now called Recreational Cyclocross (what the hell is that?) and gravelbiking. I got some very good advice talking me out of single ring.

1) It's not like you save a lot of weight. By the time you add on appropriate chain retention (diff RD, bash rings, chain holders etc) you're not much lighter than you were before. Grams don't really make a difference in cyclocross anyways.
2) Chainline. Chainline will always be better with two rings. When you're in the big cogs you'll be in the small ring closer to the frame and when you're in the little cogs you'll be in big ring further out.
3) Gearing. You can have a wider spread and tighter gear intervals between them with two rings. You'll be covered for fast courses and slow courses, without having to worry about changing cassettes and your one ring.
4) No dropped chains Why would you want to risk that? I've never dropped a chain with my two ring set-up and I don't have to get a roller clutch RD, funky chain retainers etc.

Sure I spend more time on my little ring than my big ring but so what? The big ring and FD are holding the chain in place. I run a simple chain retainer on the inside so when in the little ring where I spend most of my time the chain is effectively sandwiched, and the FD is also holding it in place. My race on Sunday was dry and fast and I got in my big ring in two places on every lap and was glad of it.

Also here's another advantage of two ring: you can run fewer cogs in the back. I run 8-speed. If I was going to single ring, I'd probably be looking at 10 or 11 speed. What's so great about fewer cogs? Well they are generally thicker and therefore tougher and will last longer - not insignificant in 'cross with all the mud and sand. Also the gaps between the cogs are wider and I think they are less likely to get gummed up with heavy mud and grass blades twisting around etc. So in extreme conditions 8-speed will run longer before clogging and failing.

Here's one thing you can do, if you find your rarely use the big ring, get a smaller one like a 44 or 42.

Andy_K 

I used a 1x10 setup for a couple of seasons with the usual "I never use my big ring" reasoning. The first year I used a 36T ring. The next year I used a 38T ring because the 36t was giving me too many chances to be slow.

This year, borrowing an idea from Katie Compton, I'm using a 2x9 setup with a 46/34 crank and a 12-28 cassette. Instead of starting in the small ring and switching to the big ring when I'm going fast enough I start in the big ring and only drop to the small ring when I need it. I'm using a Gevenalle HOUP which helps a bit with the chainline. There have been several races this year when I've done the entire race in the big ring and I've definitely seen an improvement in my speed on the flats. Basically it has favorably changed the way I think about gear selection.

I'd like a 44/34 or 42/34 setup, but I also want clean shifting and am not ready to shell out for Wick Werks chain rings yet, though I am thinking about it.

grolby

Agreed, Niloc, I really don't get the whole 1x thing. I mean, it makes sense in that modern derailleur capacities and 10/11 speed cassettes let you have a perfectly adequate gear selection with a single front chainring, but I can't see how it makes sense to swap a perfectly good double setup ib a bike you already have. Taking adequate steps to avoid dropping the chain means spending a significant amount of money on an appropriate chainring and a roller clutch rear derailleur. On a brand new bike, sure, that's fine - but even there, CX1 is SO expensive that I can't see how most people justify it. Over time, though, I think 1x drivetrains are probably going to gradually take over.

bdcheung

I recently converted to 1x10. Here's what I did:

- Gutted my left Force shifter
- Replaced RD with SRAM X9 Type 2
- 11x32 cassette
- Wolf Tooth 42t narrow-wide chainring
- Remove FD
- Remove FD cables/housing

No chain stoppers, chain watchers, or anything else. The added tension of the X9 plus the wide-narrow chainring have kept the chain on through the bumpiest courses, where others with double-chainring setups were dropping chains.

GoRacers

I run a 1x9 on my "cross bike". 42t with an old 46t ring (teeth removed) on the outside. Third eye chain watcher inside. Dropped my chain once in about 200 miles, because I timed a jump wrong going downhill at a pretty good clip.

jfmckenna

over the last 15 years I went from a 1x8 to a 1x9 and now use a 2x10 mostly with a 43T chainring and either a 13x26 or 12x27 cassette. I think in most cases if you feel like you need to spin a 32 up a hill you would be better off just running it YMMV. I rarely use the big ring in a cross race but it's there if I need it. You will absolutely definitely need something to protect the chain from falling off. Just leaving a front derailleur on there really low works just fine or you can get the double chain guards which is fool proof. I thought the one by X was a great set up but when I bought a new bike a few years back with the 2x10 I just decided to leave it there. That way I have a 1x10 set up and then if I need a 2x10 set up I have that too

Plus as part of cross training I like to ride the cross bike on the road and spinning a 38x12 down a mountain side is no fun