# Tell why I should not go with a single chainring...



## jobster (Jan 7, 2009)

*Considering going with a single chainring...*

I've just finished my first season of 'cross and am now considering upgrades/changes to my ride. Right now I'm running a double up front (46/36) with a 12-26 in the back. Of the ten or so races I've done this year, I can probably count only a handful of times where I've actually used the big ring. I really don't see a huge need for the 46T at all, but If I switch to a single ring, I'm a bit concerned with running out of low gears. I'm definitely a spinner and I find myself in the bigger cogs quite a bit. I'd like the single ring for the simplicity and weight savings, but I want to be sure it's a worthwhile tradeoff.

If I do switch, any advice on what size ring to run? I'm thinking perhaps a 38 or 39, or maybe even something larger like a 42, although I feel the 42 that might be too much of a compromise on the lower gears for me. In any case, I'll probably still change to 12-27 or even 11-28 in the back so I can still ride the steep stuff.

Thoughts?


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## agm2 (Sep 18, 2008)

I switched to a single chainring. I don't miss the big ring at all. I had a 42 off a road triple and the 39 off a double that I use. I put on the 42 for the first race and I paid for it. Lots of mud and climbing. So I switched to the 39 and I've been happy about it. I have yet to find a place where I'd like a bigger gear. Fyi, 39x11 at 90 rpms is 25.5 mph, plenty fast enough for my tired legs. But with both chainrings I can switch it up according to the courses. The next course is deadplan flat and as long as it's not muddy I'll put back on the 42. 

I'm running 12-27 in the back.


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## EricN (Apr 9, 2009)

I've always run a 42 single with carbon guards, and have had good luck, like the setup.

I've thought about going to a double in the past for ultra low gears or for a big ring shift on starts but never pulled the trigger. Single has been great for me for the past few years, and now there's a ton of cassettes that offer big range (12x27) if you're running sram/shimano so there's some definite options out there for a 1x10 setup.


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## ooboohabanero (Nov 4, 2009)

i will soon go to a BETTER single ring....just making do with what i have....old Giant 21 speed with the two big rings all messed up and missing teeth.....so i am riding a front ring with only 30 teeth or so! o well...but it sure is light(er).


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## jmoote (Nov 29, 2007)

39t with the 12-27 or 11-28 will give you about the same low gear you have now, and especially with the 11t will be enough top end. If you get significantly stronger you can go to a 42t later, but it sounds like right now that would not be the right choice for you.


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## jroden (Jun 15, 2004)

i like the 39 for very steep hills and for trail riding and hills on the road. I use a 42 big ring and could hack it for most courses with a 27, but I often use a 25, so the 39 gets used from time to time but not much. You need to have a system to keep the chain from falling off or it will.


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## jmoote (Nov 29, 2007)

jroden said:


> You need to have a system to keep the chain from falling off or it will.


True. Double guards or outer guard and jump stop is necessary. I've seen a few guys with the new Paul chainguide, but I'm not totally sold on it yet.


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## Kram (Jan 28, 2004)

39 x 11-26 or 12-26 here, depending on which wheelset I use. Never wished I had a taller gear, and although there were times I wish I had smaller one, it's best that I didn't (I'd have gone even slower.)


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## seahuston (Sep 2, 2005)

If you also train on the road on your cross bike (highly recommended) during the week then I would hang onto the double. I train on my cross bikes and a single would be sweet for racing but I wouldnt be able to get enough gear range on the road for some workout.


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## cyklopath (Feb 24, 2007)

I rode my first race on a 1x9 the other day. Liked it a lot. Simpler, easier, less to break. I use a chainring guard and an N'Gear Jumpstop to keep it chained up. 

Like AGM, I ran a 42 on it whenI test rode the course, and switched to a 39 for the race. I run a 39 tooth Shimano non ramped ring, and a 12-27 dura-ace cassette.


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## pretender (Sep 18, 2007)

seahuston said:


> If you also train on the road on your cross bike (highly recommended) during the week then I would hang onto the double. I train on my cross bikes and a single would be sweet for racing but I wouldnt be able to get enough gear range on the road for some workout.


Couldn't disagree more. 42 x 12-27 is more than enough gear range.


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## Andrea138 (Mar 10, 2008)

I use a 40t up front and 11-26 in the back. Even the one time I had an all-out sprint at the end of the race, I don't think I used the 11.


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## dasams (Oct 6, 2009)

pretender said:


> Couldn't disagree more. 42 x 12-27 is more than enough gear range.


I have 42 and 30 rings from my Campy triple and treat it as a 42 single. Great set-up with my 13-29 cogs. I use the 29 to climb hills that others walk.:thumbsup: dave


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## kc929 (Dec 12, 2007)

This is my comeback season (10 years off) so I'm not super strong. I'm running a 38 up front and a 11-25 10 speed in the rear. I'm using a Paul's Chain Keeper. This set up is working perfect for me this season. My first 3 races I had a double and kept loosing my chain. I haven't had a single problem since I switched to the single/Paul's.


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## argylesocks (Aug 2, 2004)

pretender said:


> Couldn't disagree more. 42 x 12-27 is more than enough gear range.


and I will have to disagree with this 

yes, this is gear range meets 95% of my needs during a cross race... but on the road?? no way, not enough gears to do any real training.


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## pretender (Sep 18, 2007)

argylesocks said:


> and I will have to disagree with this
> 
> yes, this is gear range meets 95% of my needs during a cross race... but on the road?? no way, not enough gears to do any real training.


42x12 with road tires is 92 gear-inches. At 90rpm, that's 25mph. At 105rpm, 28.7mph.

Unless you have the time trial result to back it up, I call B.S. on your "real training".


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## RacerJRP (Jul 25, 2007)

I have only done two races so far buit have been runing a single ring setup. A 34/ 12-25. Have never had a problem yet. Thought about going with a 12-27 though but havnt made that change. At 100rmp (Im a spinner) that gives me ranges from like 10.8mph to 22 or 23mph. In a sprint at a real sprint cadence (over 140) I can get the 34-12 over 30mph...Seems like more than enough gearing to me?


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## dasams (Oct 6, 2009)

argylesocks said:


> and I will have to disagree with this  yes, this is gear range meets 95% of my needs during a cross race... but on the road?? no way, not enough gears to do any real training.





pretender said:


> 42x12 with road tires is 92 gear-inches. At 90rpm, that's 25mph. At 105rpm, 28.7mph. Unless you have the time trial result to back it up, I call B.S. on your "real training".


+1. I have no problem riding with the big boys using my 42x12. Of course, you have to be able to spin smoothly up to 110 or 120 rpm. If you can't, then that's an area to target for 'real training'. dave


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## dave2pvd (Oct 15, 2007)

dasams said:


> +1. I have no problem riding with the big boys using my 42x12. Of course, you have to be able to spin smoothly up to 110 or 120 rpm. If you can't, then that's an area to target for 'real training'. dave


+1

I train on a 42 x 11-23. Unless you encounter downhill sections miles long, it's a perfect training set-up.


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## argylesocks (Aug 2, 2004)

pretender said:


> 42x12 with road tires is 92 gear-inches. At 90rpm, that's 25mph. At 105rpm, 28.7mph.
> 
> Unless you have the time trial result to back it up, I call B.S. on your "real training".



oh boy.. i love when people call BS on anything they don't agree with. i didn't say you couldn't do it... I just think that if a single ring was optimal for "real training", then you would see all road racers switching over to a single 42 ring. why bother with a 53, right?

you guys don't do any sprint work? and there are no climbs where you live? no mid-week training races? fast group rides?

again, of course you can get your training done with a single 42 ring.... I just think there will be times you are wishing you had a 53, when you are on the road.


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## pacificaslim (Sep 10, 2008)

pretender said:


> 42x12 with road tires is 92 gear-inches. At 90rpm, that's 25mph. At 105rpm, 28.7mph.
> 
> Unless you have the time trial result to back it up, I call B.S. on your "real training".


The problem I'd have wouldn't necessarily be the high gear, it'd be the low gear. I'd never pedal up the hills around here in a 42-27. Especially off-road. Even if I wanted to subject my knees to mashing that gear, I'd likely have to stand up and then the skinny cross back tire will spin out in the dirt.


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## dasams (Oct 6, 2009)

pacificaslim said:


> The problem I'd have wouldn't necessarily be the high gear, it'd be the low gear. I'd never pedal up the hills around here in a 42-27. Especially off-road. Even if I wanted to subject my knees to mashing that gear, I'd likely have to stand up and then the skinny cross back tire will spin out in the dirt.


You raise a good point about training vs racing. I have a triple in which I replaced the 53 with a chain guard and race on a 42 'single'. The 30 is still there for training on the steep climbs but has never been used in a race. IMHO, a bike set-up like this is near optimal and I find the gearing more useful than the typical two ring cross set-up of 34/48 or whatever. dave


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## seahuston (Sep 2, 2005)

Hmm, didnt think that the racing vs training would bring up so much disagreement.
I'm with Argyle on this one. 28.7 max speed at 105 RPM is pretty slow considering that roads are more than just flat and sprint workouts (perhaps not unanamous) and even short (1-2 min) efforts can get up around 30 mph. A 46x12 at 105 RPM is 31.5 MPH which is still a bit slow for a sprint. 
I guess training could be done single but I think I would get frustrated during intervals when factors such as slope/wind made me unable to pedal or put out consistent power. I am not saying it wont happen with a 46x12 but it would be less likely. 
The low end is not so much effected as a 38/39x25 will give about the same speed as a 42x27 from my findings with a gear calculator.
(edit)Went back and looked at my data, 105 is not an accurate sprint cadence for me as I tend to spin higher. Even so I spin out the 46x12 most of the time in these workouts so I imagine a 42x12 would spin out earlier.


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## rkj__ (Mar 21, 2007)

My take.

For cross racing, a single ring is fine. If all you do on your cross bike is race cross, you probably don't need a double. 

If you use your cross bike on the road a lot too, you might find that a two ring setup is better suited to your needs.


Personally, I use my cross bike for all kinds of stuff. When racing, I tend to stay in the small ring. The extra weight of the two ring setup is not a factor. Seriously. When I go for a road ride, and find myself with a nice tailwind, I'm happy to still have the big ring.


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## artnshel (Jun 29, 2004)

The single ring has been great for me and I whole-heartedly recommend it for racing, I enjoy sprinting when I can and it's been enough gear for the Colorado races. However I can't do short, 1 - 2 minute, intervals on flat roads with my 40 x 11-26. I have to ride my road bike.


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## Andy STi (Sep 13, 2009)

I guess I am the opposite. I almost never find myself out of the big ring. Granted I am not using the bottom cogs much but I have just always preferred the feeling of the bigger rings. Of course I use the 36 for uphill drags and steep hills but I go right back to the 46x25 or 23 to get going again. That being said, I would like to get another bike and have a single ring set-up on it.


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## OTG (Nov 16, 2001)

A single chainring is fine, even for training on the road. I rode all last winter with a 42 chainring & 12-27 cassette. I didn't have any problems keeping up with the groups of cat 1- cat 3 riders I was training with (at least no problems related to gearing).
And I live in Vermont, so yes we have hills. Up AND down.
No, it's not ideal for downhills & tailwinds, but if you spin fast enough you WILL get a workout. And if that downhill or tailwind is really ruining your sprint workout, try turning around.
It's not as easy, but we don't race cross because it's easy, now do we?

Anyway, nobody ever tells the single-speed guys that they shouldn't ride their bikes on the road.


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## JPHcross (Aug 15, 2006)

I ride a single 42 with 12-25, love it. But my CX bike is a dedicated CX race bike. If I am going to do a road training ride I ride my road bike, I would never, never, never put road tires on my CX bike. If you only have 1 bike that needs to do everything than a double chainring is necessary. A couple of my teammates are in this boat and they have 53/39 on their CX bike, at CX races they just ride the 39 like it was a single, but can switch to road wheels and have the full range of gears needed to ride on the road. CX is not important to them though, it is only used to keep some fitness through the winter.

Before I made the jump to a single ring I did a transition stage to test it out with a 42/38 front with a 12-25 and tried to race only in the 42, but found myself in the 38 at first, but eventually developed the mental and physical strength to stay in the 42. I bet that there is plenty of people who are starting out who would benefit from this gearing or even a 42/36 because a 46 is a very big gear to push for average riders on most CX courses.


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## jobster (Jan 7, 2009)

Some good responses here- thank you!

Just to be clear, I do have a dedicated road bike I use for training and racing. Having said that, I do use the CX bike for road training when the weather is crappy outside (I use my road wheels, not 'cross tires). My thought is to keep the double on it (and FD, of course) for most of the year so I can continue to use it as my bad weather road bike, but throw on the single in the fall and use it as a 'cross-only bike.

This leads to my next question: when converting from a double to a single, can I just change out the rings or do I need to get a different crank as well? Right now I just have an FSA gossamer crank (46/36, 110mm BCD) and would most likely go with a single 39T. I'm thinking that a 39T will only come in 130mm BCD, so I might have to change out the whole crankset anyway. I'm not sure if this might be more trouble than it's worth, but I thought I'd throw it out there for thoughts.

By the way, I use a compact crank on my road bike (50/34).


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## hoogerland (Sep 18, 2009)

I'm running a 40T, 11x26 with a Paul's chain keeper. My drive train has been flawless so far in 10 races. I have been doing tabatas, so 7x20s max effort from next to standing still. No problems training with this setup. Like Art said, longer intervals might be problematic. I love the setup though - simple, light, efficient and reliable. In a couple of weeks I'll be putting on my FD and rings for winter group rides...unless a Winter/Spring CX series happens...rumored.


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## dasams (Oct 6, 2009)

jobster said:


> This leads to my next question: when converting from a double to a single, can I just change out the rings or do I need to get a different crank as well? Right now I just have an FSA gossamer crank (46/36, 110mm BCD) and would most likely go with a single 39T. I'm thinking that a 39T will only come in 130mm BCD, so I might have to change out the whole crankset anyway. I'm not sure if this might be more trouble than it's worth, but I thought I'd throw it out there for thoughts.


You can buy a 38, 40 or 42T ring for the inner position and a chain guard for the outer position for your 110 BCD cranks. Depending on the terrain and your cogset, you may try just replacing the outer ring with a guard and running the 36. Available at many places such as cyclocrossworld dot com. dave


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## Dan Gerous (Mar 28, 2005)

I finished my first cross season yesterday, 2x10 but I think I'll go 1x10 for next fall. I'm geared with road compact rings (34/50, I use my cross bike to train, to do group rides and even entered a few road races so I need a bigger chainring than what a single ring for cross would be) and I'm obviously too between rings with those when racing cross, I'll probably get a 40 or 42 with a 11-27 or 11-28 cassette but that's all depends of when/if I get a dedicated road bike. I'm a big fan of elimitaing front shifts. I'm converting my mountain bike to a 1x10 too.


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## colinr (Nov 20, 2006)

So if the OP is running a 36/46 and doesn't use the 46 enough... just use a smaller big ring. Don't have to go to a single. Run a 36/44 or 36/42.

For the guy who called 140 rpm "real sprint cadence"... dude we're not track sprinters here. With legs full of lactic after 45-60 mins, I get my best torque/watts at 90 rpm. 42x12 at 90 rpm is NOT sprint-winning speed for me. YMMV.


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## GearDaddy (Apr 1, 2004)

I've been using a single ring setup with a 42T, outer chain guard, and 3rd-eye chain watcher for the last 3 years, and I'm quite happy with it. I switched from a double to a single because I had one too many times where the chain came off with the double setup during a race. Since running the single ring setup, I have had absolutely zero problems with my drivetrain in those 3 years.

For just a couple races where there was a pretty steep but rideable hill, I switched out to a 38T chainring. Otherwise a 42T with a 12-25 or 13-26 (I'm running 9-speed Campy) has worked great.

As far as training, I just keep CX tires on and the gearing works just fine. I've discovered that the most effective CX training for me is to do relatively short workouts (i.e. 1 to 2 hours) where I ride at a pretty intense pace on a mix of trails, roads, paths, and do "hot laps" at a local park where I can include some runups, dismounts, and such. I did hardly any road bike rides at all this fall and I've had as good of results as ever. I see no need to do 3+ hour road rides, much less do any sprint workouts.

I also use the same CX setup for the majority of my early season spring road rides. I just throw on some older CX tires that have been worn down smooth in the center of the tire. It's perfect for spring roads around here that have all sorts of crap on the roads. The tires roll well enough and the gearing is fine for the pace of the road rides with training partners at that time of the year.


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## cogswell23 (Aug 15, 2007)

colinr said:


> So if the OP is running a 36/46 and doesn't use the 46 enough... just use a smaller big ring. Don't have to go to a single. Run a 36/44 or 36/42.
> 
> For the guy who called 140 rpm "real sprint cadence"... dude we're not track sprinters here. With legs full of lactic after 45-60 mins, I get my best torque/watts at 90 rpm. 42x12 at 90 rpm is NOT sprint-winning speed for me. YMMV.


As usual, Colin gets it. 

I mean, I can understand folks running a single 42t ring, sorta. I wouldn't do it, but I get it. But running a single 38t or 39t like a lot of y'all apparently do? That's for the birds as far as I'm concerned. I'm a small guy, not super powerful. I run a 39/46 up front, with 12-25 in the rear, and I'm almost always in the big ring. 

So the way I see it, if you're going to run a single 39t ring, why not double up and throw a bigger gear on it too? Even if you spend most of your time in the 39, that bigger ring *will* come in handy for you sometimes. I promise.

Remember, my friends, races are won in the big ring. Even if it is the race for 44th place.


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## Kram (Jan 28, 2004)

Well. I've won "sprints" for 44th (or whatever) place in my 39x11. Just sayin.


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## jmoote (Nov 29, 2007)

All of you folks who love the 46t so much seem to be running cassettes with 12t as the smallest cog. You do realize that by using an 11t the 42t offers almost the same gearing:

46/12 = 3.83
42/11 = 3.82

I understand that 12t cassettes used to be the norm, but these days I never choose one given the option for 11-25 or 11-26, etc.


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## colinr (Nov 20, 2006)

jmoote said:


> All of you folks who love the 46t so much seem to be running cassettes with 12t as the smallest cog. You do realize that by using an 11t the 42t offers almost the same gearing:
> 
> 46/12 = 3.83
> 42/11 = 3.82
> ...


I have an 11. 46x11 = 4.18. I agree with your point though.

It should be noted that 46x11 is bigger than 50x12, and people use the latter on road compacts. I have done road races with 46x11 and it's never been a problem.


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## jmoote (Nov 29, 2007)

colinr said:


> I have an 11. 46x11 = 4.18. I agree with your point though.
> 
> It should be noted that 46x11 is bigger than 50x12, and people use the latter on road compacts. I have done road races with 46x11 and it's never been a problem.


Yes, we're very much in agreement here. I've done a road race on a cross bike with a 46x11, no problem. It's not the kind of gear you will use much if ever in a cross race, save maybe a sprint (and no, not the sprint for 44th, the 46x12 or 42x11 will be fine for that  )


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## matthewtucker (Aug 7, 2007)

*42 with an 11/28 cassette*

You get nearly the entire range that you'd have with a 38/46 with an 11/25 cassette. 

:thumbsup:


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## krisdrum (Oct 29, 2007)

Man, this is humbling. I ran single ring this season because I knew I'd never need more with either a 12-27 or 11-28 on the back. I started off on a 38 on a very flat short track course. Switched down to a 36 for most of the rest of the season and ultimately wound up on a 34 for the last few races, as I was looking for more gearing. With the 38 and 36 on most courses I was running a single speed for all intents and purposes. 

Now granted, this is my first season racing and although I committed to racing I didn't really commit to my fitness (sadly) and I am a self-defined spinner, but found a 42 single too tall on the road for me! I am used to a compact double 50/34 though. I guess I need to start training myself to be more efficient and spin larger gears, because I obviously can't hang with a 42 in competition.


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## jmoote (Nov 29, 2007)

This is of course a key issue with the single ring: not everyone needs the same size ring. Pros running single rings back when this was in style were using 42 and sometimes 44 to race World cups. These days, 42 is pretty much standard for single setups, but if you're racing cat 4 or whatever there's no shame in running smaller. The race is slower so naturally the gears used are smaller.

My first year of cross I raced 46/36 double and spent lots of time in the bottom of the cassette on the 36. One year later I was pushing a single 40 or 42 no problem. At some point a 46/xx double may be needed, or not.


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## krisdrum (Oct 29, 2007)

jmoote said:


> This is of course a key issue with the single ring: not everyone needs the same size ring. Pros running single rings back when this was in style were using 42 and sometimes 44 to race World cups. These days, 42 is pretty much standard for single setups, but if you're racing cat 4 or whatever there's no shame in running smaller. The race is slower so naturally the gears used are smaller.
> 
> My first year of cross I raced 46/36 double and spent lots of time in the bottom of the cassette on the 36. One year later I was pushing a single 40 or 42 no problem. At some point a 46/xx double may be needed, or not.


And I'm a slow 4 on top of it. :wink:

I can pretty easily maintain 95-100 rpm on the road in the 34 and about mid-cassette and just spin til the cows come home. Not so much in cross. I'm definitely aiming to get stronger/more fit/more efficient in putting power down in the off-season, as I'd like to try my hand at some cat 5 crits in the spring before my baby arrives and then hopefully re-focus on cross again in the fall.


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## tedgrant (Jun 13, 2006)

I use a 40t ring up front and a sram 11-32 rear 9 speed with a dura ace short cage derailleur.
plenty of top and low end

best shifting performance with the exception of the mighty XTR 8 speed set (why cant they bring that back, the only drivetrain that actually works in mud)


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## carlhulit (Nov 5, 2005)

I have run a single ring in the past (42) but switched to a 39x46 with an 11-26 this year. I am a competitive 1/2 racer in a fast field so my gearing needs are higher than the OP (36-42 is a good suggestion) but i think a double is where its at. I generally split my races between the gears, flat races I will stay in the big ring, for hills I like the small ring and when you get a transition section the bigger shift from the front is nice to have. Yes I could cover my gear range needs with a 42x11-26 or 28 but in the mud i would much rather be in a 46-15 than a 42x13 because my chainline is better from the outer ring and there is more chain tension to fight the mud, in general i find the bigger ring bigger cog combination to work better, and the smallest cog almost never works in the mud so a 42-11 is great in theory but not in practice. Bumpy ground also is faster in slightly harder gears.


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## pacificaslim (Sep 10, 2008)

jmoote said:


> All of you folks who love the 46t so much seem to be running cassettes with 12t as the smallest cog. You do realize that by using an 11t the 42t offers almost the same gearing:
> 
> 46/12 = 3.83
> 42/11 = 3.82


Sure. But they say gears that use bigger chainrings and cogs are more efficient and longer lasting than equivalent gears made up of smaller chain rings and cogs.
It may be minimal, but the guy with the 42/11 will have to replace his chain and ring and cog before the guy with the 46/12. The 42/11 rider will also lose a bit more power because of drive train loses than the 46/12 guy.


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## Dan Gerous (Mar 28, 2005)

pacificaslim said:


> The 42/11 rider will also lose a bit more power because of drive train loses than the 46/12 guy.


I doubt any human could notice a difference, even if his name is Sven Nys...


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## ringcycles (Dec 30, 2008)

I know plenty of guys who are competitive in the elite and masters 35+ 1-3 races running a single 42. That said, I found that I dropped my chain too much when I was running a single ring. With a double I can use the FD to get the chain back on 80% of the time w/out dismounting. Single ring you drop a chain and you have no option. I also dislike being cross chained as much as a single ring forces me to be on fast or hilly courses. I tend to run 46/38 w/ a 12-25 cassette just like Sven.


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## argylesocks (Aug 2, 2004)

ringcycles said:


> I know plenty of guys who are competitive in the elite and masters 35+ 1-3 races running a single 42. That said, I found that I dropped my chain too much when I was running a single ring. With a double I can use the FD to get the chain back on 80% of the time w/out dismounting. Single ring you drop a chain and you have no option. I also dislike being cross chained as much as a single ring forces me to be on fast or hilly courses. I tend to run 46/38 w/ a 12-25 cassette just like Sven.


I have/had dual guards on my 42 and have never dropped the chain... not sure if its even possible. but you bring up a good point, about the chainline. my new frame is a BB30, but im using an adapter... unfortunately, it puts the crank just a bit further out than previously.

the chain rubs on the inner guard when in the 27... when its muddy, it sounds horrible. eek. I ended up taking off the inner guard, and moving the chainring to the inner location. chainline is much much better, but now i have to use a N-gear... we'll see how that goes.

and yes, when I see Sven, I think 'yeah, carl has that same setup'


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## gewilli (Dec 18, 2006)

i didn't get out of my 38 either day at Sterling, but i'm not taking my double off...


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## CouchingTiger (Mar 5, 2007)

I've been running a single 40 with an 11-28 cassette for a couple years now. The math looks something like this according to Sheldon's calculator (700c x 32);

26.3mph @ 90rpm (40x11)
27.6mph @ 90rpm (42x11)
30.2mph @ 90rpm (46x11)

I actually do better sprinting at 100rpm or so, which puts me at 29.2mph. No offense but you will be hard pressed to see that. The fastest sprint I've had was at the NoHo course this year (slightly down 100 yard paved straight). I won the 3 up sprint I had going and never felt lacking in gears. I don't feel that I've ever spun my cross gear out, though that may just mean that I'm not going fast enough. I have, however, spun out a 53x12 on a fast road course downhill section.


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## jobster (Jan 7, 2009)

CouchingTiger said:


> I've been running a single 40 with an 11-28 cassette for a couple years now.


I've been considering this very gearing combination myself, or even a 39t with a 12-27. It seems to me that this will give me all the gearing range I will need during a race. I too tend to spin more and would always be 100+ rpm in an all out sprint, so I'm not overly concerned about losing a lot on the top end. Plus, I'm only racing Cat 4 at this point. Heck, if there are guys out there racing in faster categories than me and they're happy with this combo, it surely should work for me.

Thanks for sharing your experience.


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## jmoote (Nov 29, 2007)

pacificaslim said:


> It may be minimal, but the guy with the 42/11 will have to replace his chain and ring and cog before the guy with the 46/12.


You're not cruising around in the 42x11 all the time, so this has no bearing on how often you replace parts. That gear is used maybe once a race, so it has almost no impact on wear. The single ring when sized correctly for your ability will have you mid-cassette for 90% of the race.



> The 42/11 rider will also lose a bit more power because of drive train loses than the 46/12 guy.


It's been mentioned already, but the bit about drivetrain losses is a load of crap from a practical point of view. The larger ring/cog combo is more efficient on paper, but the efficiency of all bicycle gear systems is all on the same order of magnitude so it's really quite non-consequential.


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## pacificaslim (Sep 10, 2008)

Forget the wear on the cog then and just realize that the 42 will wear out faster than the 46 and the chain will wear out faster as well. As I said, "it may be minimal," so clearly I was speaking mainly theoretically and it is not necessarily something we should worry about.


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