Because people want narrower gaps between gears and often want an easier gear than 46x32

I guess I understand the narrower gaps, although when I started racing I only had 12 gears with a double chainring. And this way you wouldn't have any overlaps. You might be right about the low-end, though I think there are probably a fair number of folks who don't need anything easier than a 34-24. That's a pretty low gear.

Also, I would suspect it is because a front derailleur isn't really much of a "hassle", once you've actually set up your bike It's a solved problem. And on a tri bike, the extra weight of the front derailleur/chainring is negligible -- unless you are on a course where you need that easier gear...

42t single with 165mm cranks
12/25t 8sp cassette (the left bar end shifter is just on for symmetry/weight)

I custom geared it for myself, riding 13 - 21 mph on flat roads with 90 - 100 rpm. I use my road bike on hilly terrain.

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Two wheels good. Four wheels bad.

Neat. Have you had any problem losing a chain? I know the SRAM rings have teeth specially designed to keep the chain on.

No, chain is staying on without a problem. You have to make sure your chain line is good, and that your chain length and derailleur cage size are optimal and match. Its a 20+ year-old Shimano Exage derailleur off my 1992 F. Moser steel vintage….. reuse and recycle. Happy riding.

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Two wheels good. Four wheels bad.

Sweet setup, nice idea.

Quite a few people did back in the late 80's/ early 90's. Apart from the chain drop issue, a double is just the standard. The small ring can be really save your running legs if an unexpected headwind shows up. The weight and aero penalties are pretty small.

I would be into it. After playing around with the Sheldon Brown gear chart, I did a 1X10 conversion for my CX/Commuter.

Picked up a Wolf Tooth 42T chainring and run an 11-28 cassette. That works great for just about everything around town and some hills. I could see gripes of big gaps while climbing and running out of gears going downhill. Would work great for my road bike (no road races for me), but I don't know I would want to race on it if I wanted to keep a cadence/wattage range.

I have another Wolf Tooth ring coming for my mtn bike and my next project is to change the roadie to probably 44/11-32.

But I'm keeping 53/39 with my 12-27 to race triathlons until I get my 1X12!

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/kj

http://kjmcawesome.tumblr.com/

I think sequential electronically shifted/gearing with a 2 x 11s system would be far more useful for triathlon.

If MOP triathletes are riding at 70-80% of FTP on hilly or windy courses a 1x system will not be enough.

If you're a time trialist on the other hand, riding at 100-110% of FTP on flatter courses I can see the 1x system having some merit.

The drag and to a lesser degree the extra weight of a front shifter and front derailleur could certainly be the difference in a short distance effort.

-SD

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https://www.kickstarter.com/...bike-for-the-new-era

I'm using a 44t wolftooth and 11-32 cassette on my rain bike (road bike) and I haven't wanted more gears on either end - I dont think I'd want to race it though.

I'm also using a wolftooth 40t ring and 11-32 on my CX race bike and it has been awesome. I paired it with a SRAM XO clutch RD - very nice setup.

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Yeah I had an 11-25 cassette on my CX race wheels and I felt a little over-geared. I think your setup is better. I'm using a regular non-clutch RD and haven't had any drops. The chain does bounce around though.

But riding 1X is a blast. Almost like a single speed, with the exception that you can actually find the right gear.

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/kj

http://kjmcawesome.tumblr.com/

The clutch RD really helps with chainslap and drastically lowers the chance of chainsuck in really muddy conditions. I had some chainsuck problems in a muddy race using my force Wifli RD before I switched, and it didnt happen again in similar conditions with the clutch.

I find the bigger spacing on 11-32 cassettes actually better for CX as the courses normally require that (steep up and downs) - at least in my area. Road cassettes have me shifting way too much.

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1x8 speed 54t x 11-28

Here's one reason...

https://www.youtube.com/watch?v=U7Tx6MV_XyM

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Kevin

http://kevinmetcalfe.dreamhosters.com
My Strava

I don't see that much of an upside to it. Riding in a 30 mph wind either into it
or with it there's plenty of downside to not having the right gear for the job.

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Find out what it is in life that you don't do well, then don't
do that thing.

Also, I would race on a 1x front but maybe not want to train on one. Well come to think of it I never use little ring and have 11-25 in the back so maybe I'd go for it. I always muscle up the 100-200m inclines in my area instead of shifting.

But definitely not in hillier locals.

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Very cool,

For this of you on 1X10 how have you solved the chain falling off on the outside?

I am on Q-rings so I think this is mostly the issue.

Just wondering if anyone had any tricks.

Great thread,

Mauroce

My legs hurt just thinking about a 54/28 as my lowest gear.

I agree that it will work better for some than for others. I'd like to shed a few grams and I suppose there's some aero benefit. My chief reason (if I were to switch), is that it can be a PITA shifting chainrings at certain moments in a race. I run mechanical dura-ace, so it's not as smooth as electric. I think I'd just prefer to not have to deal with a front derailleur and get all my gearing taken care of in the rear. Less to think about and mess with during a race (as long as I can get the right gear spread).

The shorter your races and the stronger you are the more likely this is to work.

What will suck is when it doesn't work, it will be a huge pain in the ass.

Sign up for IM France, or Savageman? Race ends up having a nasty head wind? too bad.

I think a 52 front with a 32x11 cassette, 11 speed, could do pretty well almost all of the time though.

You will want a custom single speed chain ring with deeper teeth so there is less chance of chain popping off.

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Kat Hunter reports on the San Dimas Stage Race from inside the GC winning team
Aeroweenie.com -Compendium of Aero Data and Knowledge
Freelance sports & outdoors writer Kathryn Hunter

I got my front ring from Wolf Tooth Cycling (from an ST recommendation). Designed to be run as a single ring and haven't dropped a chain yet.

I think the biggest ring they make is 44t. That would work for me with 11-32 in the back. 12 speed would be ideal.

11, 12, 13, 14, 15, 17, 19, 21, 23, 25, 28, 32.

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/kj

http://kjmcawesome.tumblr.com/

wouldn't be a big seller in New Zealand.

My 34/25 combo on 650 wheels was barely, oh so barely, enough to get me up some hills at the end of Rotorua 1/2 IM

My 55/11 on 700 wheels also spins out from time to time.

Give me two chainrings and small gaps between cassette gears and I'm good to go

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TriDork

"Happiness is a myth. All you can hope for is to get laid once in a while, drunk once in a while and to eat chocolate every day"

Funnily enough I was doing some calcs on this earlier today (not having seen this thread).
47 on the front with 11s 11-30 on the back gives you basically the same range as 53/39 x 12/25
That's plenty for NZ courses.

Then a 55 x 11/25 would be right for Tauranga.

I did try riding the IMNZ course with a single 48T fixie ring. 13 chain drops convinced me that it wasn't going to be a goer for the marvellous road surface of that race. Clutch and/or narrow/wide would be needed (I tried 5 years ago when such things were only a glimmer in a designers eye).

Hills!

Brockway Summit at IMLT comes to mind.

It sounds like a solution in search of a problem to me. If it is flat enough that the small ring isn't needed then the weight penalty doesn't matter. If it is hilly enough to make the weight advantage attractive then the lack of gear range is discouraging. As others point out, wind can mess up the plan too. I could see this for some very flat events where it is inconceivable that the small ring would be used. When I was doing some road riding in South Carolina near the coast last month I didn't touch my small ring once.

I have raced (road races/crits) in my very young days (early 70's) on both a single speed freewheel as well as a 5 speed cluster. (single chain ring up front). Most of the time the single chain ring worked ok, but if you hit some bumps while putting power down... the chain did have a tendency to come off....at the worst times....after it happened in an important race, my parents bought me a custom road bike.....so it was a win in the long run...lol

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http://www.TomMoschettoFitness.com
Cycling Coach/Trainer/Motorpacing/Computrainer Rental

I think the guys behind Dimond are promoting a single ring set up, at least for some race situations.
Less drag is the main benefit.

I agree on a flat to rolling course, riding with a 50-34 and 11-28 in the rear, I'm only using the 50 with 11-25 in the back (never get into the 28). That is a 2:1 ration (50:25). when I started riding we were on a 5 speed cassette so only 10 gears back then albeit on a slightly wider range than the above. I really like never having to get into the small ring and back to the big on rollers.

One the course has more than 5-6% grades I need the small ring for sure. In any case the 50-34 with 11-28 and I have all the gearing I need for pretty well every triathlon course under the sun. I could use the same gearing from Eagleman to Alpe d'Huez tri.

Dev

Well...

I have a single on my MTB. And, I have thought of going with a single for CX.

But, I would say that for a TT, the double x 10 or 11 is the way to go. Getting the most out of a given power/cadence at each instant is of value during a TT event.

I know for myself that I am switching gears way, way more often on my TT bike than I am even on the road. I guess I'd say that the closer gear ratios are of an advantage. This is pretty much why I stay with the double for CX when I'm pretty sure in practice most CX course would allow me to run a single.

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Twitter @achtervolger

Sram just announced the Force cyclocross 1x11 setup and it includes up to 46t chainrings.

I think 1x11 is pretty appealing for general road riding/training, but in a race situation, I'd be worried about being over geared.

Although, my road and tri bike are currently 53/39, with a 12/26; a 46t with an 11/32 would be a better range.

Don't forget too, that any course with uphills also has downhills. You need to ideally apply 80-90% of your target power even on downhills. So any miniscule time savings from weight (Why do triathletes even care) would be lost by a higher VI and lower average power.

Triathletes need to mostly ignore any advice, myths, preconceptions, etc from road bicycle racing. A road bike race is NOT a TT. Fundamentally, racing a clock in a not draft legal TT, is completely different from a draft legal race for position were the finish time is mostly irrelevant other than you relative time gap to other competitors in stage racing. An age group triathlete could be very successful having never, ever produced more than 400Watts or hell maybe even 350W peak during training or racing. A CAT 5 racer would get killed other than timing a break away perfectly off a long steep climb late in a race or on a technical course.

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TrainingBible Coaching
http://www.trainingbible.com

11-30? Not for me thanks. That's pretty much 2 teeth gap between cogs? Nah. In an ideal world, a straigh block at the back (1 tooth difference between cogs) would be far nicer for riding, with shifting a 2/3 front chainring as needed.

While a single chainring and wide spaced cassette has its uses, for me, riding a double chainring with decent tooth differences works just fine. A 11-30 tooth cog out the back also means a giant rear deraillieur cage. Hardly worth the effort when a 12-25, with compact crankset covers all but the most extreme uphill, flat or downhill situations for 99.38% of road riders around the world.

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TriDork

"Happiness is a myth. All you can hope for is to get laid once in a while, drunk once in a while and to eat chocolate every day"

Haha that's the first thing I thought of as well when I read the thread title. But wasn't the main reason Millar's chain slipped was because someone on his team had the brilliant idea of taking off the FD to save weight? I think they canned one of the DS's on his team (Cofidis) after that.

My first Tri of the season, which for me, is a relatively flat course, still has one hill at 16% for a few hundred meters. Before and after that it is 8% and there is another hill at 8% as well. Even though I'm on a compact crank, I still use all gears.

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BC Don
Pain is temporary, not giving it your all lasts all Winter.

There is really no benefit to this. Basically what you will end up doing is spending a bunch of money to replace stuff you already have with stuff that isn't as versatile as what you had before. You'll have bigger jumps between gears and what will you really gain?

Even for a flat TT like in Sattley, CA all you really gain is the weight savings of a single small chainring. On a flat TT. You can't safely take off the front derailleur (see my David Millar video elsewhere in the thread). So you save probably 50-60 grams and lose the ability to cruise around while warming up in a reasonable gear at a reasonable cadence.

Total. Waste. Of. Time.

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Kevin

http://kevinmetcalfe.dreamhosters.com
My Strava

Agree that spending a bunch of money to change a bike to a 1x is silly. I did it with a Wolf Tooth chainring and my LBS gave me some chainring bolt spacers. Oh and I bought a torx bit.

But having commuted and raced CX a few times on a 1x10, it is unlikely that I will purchase another front derailleur in the future. Ever?

Wife has Di2 on her road bike and the front shifting is amazing. But still sucks compared to any rear shift I have made. Dura Ace, Red, Tiagra, etc.

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/kj

http://kjmcawesome.tumblr.com/

Not unless I lived and raced in Florida year round or if I only raced short course. For long course, it would work at a course like Texas, but definitely not Louisville or any others with a decent grade hill. Narrow gaps are also very important for hitting a target power range within an optimum cadence range.

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-Bryan Journey
Travel Blog | Training Blog | Facebook Page

I was thinking of doing this, until I actually did the math.

I calculated that if I changed from my current 2x10 SRAM Red set-up to the best spec SRAM 1x10 / 11 setup (new crankset and chainrig, new Wi-FLi RD and 11-32 cassette), I would save a huge 62g in weight. This includes the loss of weight from the FD and assuming losing 100g for the front shifter cable.

This is mostly because the best spec 11-32 casette SRAM currently makes weighs around 100g more than a 11-25 Red cassette. So changing to the bigger casette acutally results in a weight gain, even after removing the FD!

From a weight perspective, right now there is just no real benefit to going 1x on a road bike. Changing all that stuff and having worse gear ratios for 62g just makes no sense.

Obviously this does not account for the aero cost of some cable, FD and extra chainring for keeping a 2x set up. Would be interested if there have been any aero studies on a 1x vs 2x setup.

I was thinking the same thing, except my setup would be a 54 tooth big ring and using an 11 spd 10-42 with like an xtr long cage RD.... since I just did St. George, I know that I'm ok with a 42/28 equivalent of 1.5 gear ratio up the steepest climbs... so that means I'd never have to use all the way to a 42, but I could have used a bigger gear than the 54/11 on the downhills, albeit brief, but pedaling at over 40 and up to 50 has some advantages, could have shaved another 1 minute or so off the time.... otherwise was forced to coast. It would be sweet if SRAM would make a 10-36 cassette, then I'd be doing it sooner.

It certainly would be course specific. I run a single ring from time to time. My KISS solution.


-SD

That's about as simple as it gets. Was there a single-speed category in your race?

No, not in this race, but it was pretty flat and wind was only ~10-15.
At my best I'm a mid-pack TT guy so riding my track bike gives me excuses beyond my lack of fitness and inability to suffer.

-SD

Dayum......nice position!!!

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Chicago Cubs - 2016 WORLD SERIES Champions!!!!

"If ever the time should come, when vain and aspiring men shall possess the highest seats in government, our country will stand in need of its experienced patriots to prevent its ruin." - Samuel Adams

I ran CX this fall with "normal" 9-speed gearing and never left the 46-tooth chainring so it's not a stretch for CX. I also never left the 52-tooth chainring while living in the big Easy, but for other, not so flat courses, such a wide-ranging cassette would require larger jumps between gears, making it harder to find the sweet spot at times.

Am I the only one that runs the 53 on the front until I get to the 25 in the back, then I drop to the 39 until I get to the 13 in the front, then...

I don't think I ever shift the front looking for that perfect gear ratio, and I've never ridden with anyone that has mentioned doing it. If I see a hill coming up (or know one is around the corner) I will shift the front if needed in advance. Otherwise I just stay where I'm at.

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"...the street finds its own uses for things"

Ok, decided to try a 1x10 set up on my training (road) bike as an experiment. A 1x11 set up would really be ideal, but right now I don't want (have $$!) to change everything to 11sp.

I currently use 53/39 chainrings, with an 11-25 cassette. Going to run a 53t chainring upfront with an 11-32t cassette. I already had a SRAM Rival Wi-Fi RD, so I just needed a new cassette...

The 53-32 low gear will give me a ratio pretty much the same as a 39-24 - I rarely use the 25t cog anyway in any of my training rides/races, so it shouldn't be much different. If I battle I can always change the chainring to a 52 which will give me the equivalent of a 39-25..

Will see how the gear gaps are and report back in a few weeks. If it works and I don't get any dropped chains I may use this on my race (Tri) bike as well.

Oh, and on further investigation, one can get hi-spec light 11-32 cassettes (just cost $$) so the weight loss moving to a 1x setup will be more substantial than I initially thought.

Correct - subsequently saw that too, thanks. I also forget to subtract the weight of losing the front chainring, so now looking at a weight reduction around 200 - 250g...

Hey DP,

Your post about 5 speed freewheels inspired me to go look I what I had back in the day. Bought my first new "10 speed" in 1970. A Peugeot U08. I couldn't find specs on it. But a friend had a Peugeot PX-10. The specs for that showed a 14x24 freewheel with 45x52 chainrings!

Not that I choose but did my last race IM St George 70.3 with a single chainring. On the first climb (mi 2 of the race) my front derailler cable broke... Did the entire 56mi on a 39! Rode 22.2mi/h... It's a course that I could have use my big chainring many many times. In order to maintain rythm with some guys passing me, I rode on 39 x 11 at rpm well above 100. At 120rpm I was getting close to 30mi/h... Did many burst of around 125-130 rpm to pick some speed on the descent.

I shoot my legs by maintaning a RPM of between 100-110 for most of the race. My run really suffer from this. Going under gear like I did, I suspect that I lost 10-15 minutes, maybe 7-9 minutes on the bike and probably 4-7 minutes on the run for because of over spinning, I had no spring in the legs during the run.

I have a friend that goes single chainring in all his races (53) even in Kona... I think he would be faster by spinning more up the hills but that's what he decided.

front derailleur mount broke on my tri bike a couple of years ago, haven't missed the small chainring at all on my mostly flat or sometimes rolling short races in Texas. I just taped the cable to the tube so it wouldn't bounce around and never even removed the small ring, derailleur or shifter. Reading this I guess I outa take off those extras for the bit of aero/weight gain. Its a 1x10, 53 with 12/25. Haven't dropped a chain, but I pedal continuously at pretty high average cadence from habit after years of commuting on a fixie.

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some days you're the windshield some days the bug

Next time just adjust the low limit screw on the FD clockwise until it can't shift down from the big ring. Would take less than a minute to stop, adjust, get moving again. You would just need to carry a small multi-tool, or stop at tech support.

It's not the roadies who keep asking about this kind of stuff. We all watched David Millar drop his chain in the TdF prologue and know that this is a solution in search of a problem.

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Kevin

http://kevinmetcalfe.dreamhosters.com
My Strava

>Fundamentally, racing a clock in a not draft legal TT

What?

I'd love to run a single ring up front and ditch the front derailleur and shifter. I run 1x11 on my Scalpel and have yet to drop the chain. The new derailleurs with the clutch and the special front chain ring could be developed for road use. Sram has a 1x11 now for cross as well....

Thanks for the tip, I didn't thought of it.

Here's my Titanflex build with single chainring
(completed this past weekend May 31st, but no long ride report yet given my 10yr old visiting nephew gave me the Flu for the last week)

Dropped nearly half a pound (0.46 lbs) by converting from 2012 SRAM Red (50/34 Red compact crank, TT shifters, Red Derailluers)
to SRAM XX (10spd) Rear derailluer, 11/36 cassette, Wolf Tooth Components wide/narrow 44T chainring. (will use SRAM 46T CX1 Chainring when available to gain back some top end). SRAM 10 speed road shifters and 10 speed mountain bike parts are fully compatible (both use exact actuation)

44T chainring and 36T cassette yields a climbing ratio of 1.22 vs a ratio of 1.21 with the prior compact set up of 34T chainring and 28T cassette cog.
44T chainring and 11T cassette yeilds a top speed ratio of 4.00 vs a ratio of 4.55 with the prior compact set up of 50T chainring and 11T cassette cog
When I switch to 46T CX1 Chainring when available:
46T chainring and 36T cassette cog yeilds a climbing ratio of 1.28 (which is more than enough to climb the steep hills around Bloomington, Indiana easily)
46T chainring and 11T cassette cog yeilds a top speed ratio of 4.18 (just 8% less top end than compact 50/11 gearing so should be good for just about everything)

The XX Cassette Gear spacing is 11,12,14,16,18,21,24,28,32,36 which works great for hilly terrain (Bloomington, Indiana) with constant shifting required.

I hate compact crank's drop from 50t to 34t which often necessitates an upshift or two in the rear derailluer to maintain steady cadence (I'm used to the wider cassette spacing given my mountain bike background) and I hate front derailluers even more!

Bye Bye Front Derailluer, Hello 0.46 pound weight reduction and perfect shifting!
(total bike size XL as pictured below with pedals, computer and bottle holder is 18.15lbs)

pics

Like this?

[URL=http://s268.photobucket.com/...ia/IMG_3604.jpg.html][/url]

Cool setup. Seems like a smart choice of gearing, especially once you get the 46. As folks have said, the lost weight probably doesn't make that big a deal for most tri courses. But I love the simplicity of shifting straight up and down the gear range, and not messing with front shifts.

I tried running a SRAM clutch mech on my TT bike with a single ring but it was terrible for dropping the chain, it even dropped it on the turbo trainer. It seemed it might even make things worse by being quite slow to take up the chain tension when shifting to a smaller sprocket. So I ditched the clutch mech, and have since been running a Di2 rear mech with a fibrelyte ring designed for single ring use, and it has been quite good for retaining the chain, but it has still come off in my last two TTs so I'm going to have to admit defeat and put a front mech on just to stop the chain from coming off. It makes it fairly pointless going single ring in the first place as the front mech is probably the biggest aero saving.

I have a feeling a major reason MTBs can get away without something to keep the chain on is the much smaller chainrings compared to a TT setup. I once tried a 60T chainring, designed for double ring use, and the chain simply came straight off within a few revolutions if you turned the cranks on a turbo trainer in the top 2 sprockets.

In my last couple Olympic tri's and possibly this sunday I will be in my compact 50T ring the whole race so for some courses seems logical to me. But I'm not throwing down sub 1 hour 40K splits either so not sure how much I gain by lowering a few grams. Must....Keep.....working....on.....engine.....

Wouldn't have worked at Branson a few years ago and def. not Savageman.

The reason it works on the mtb isn't just the clutch rear derailleur. The front chaining has special teeth that are extra long and every other tooth is a lot wider.

The fibrelyte guy reckons people use his single rings on MTBs and tell him they work better than the XX1 rings. I just don't think the clutch mech is particularly helpful for road use, I think the main benefit of it is for coping with bumps off road, and most of the time on the road what you really need is a very fast take-up of chain slack when shifting to a smaller sprocket, particularly when shifting to the 11 which is when the chain is most likely to come off.

This doesn't work for me for two reasons. A) I can, and do, often spin out a 52x11 gear. B) The jumps between cogs on a 36x11 cassette are way too big for me. Personally I get more out of 52/38 with a 23x11 cassette. I can still climb well, it's harder to spin out and when I do I am going quite a bit faster and I get very tight, compact jumps up and down the cassette.

That said to each their own and I am glad to hear it works for you.

Now on a MTB I completely agree with you :) On a MTB I am never spinning out as I am hanging on for dear life well before that happens and the extra big cogs sure make it easier to climb rocky and rooted routes.

I'll edit this to add it might also be different on the distance of your race. Hammering hard in a sprint or Oly you might need more than the 46x11 but long steady efforts like 70.3 or 140.6 it might be sufficient.

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Rodney
TrainingPeaks | Altra Running | RAD Roller
http://www.goinglong.ca

Pro cyclists tried that with bad results(chain falling off). Very little upside.

I can't get beyond those statements! You're 'often' going over 70hm/h (52x11 at 120rpm)? I live in Burlington too. You might hit that on the occasional escarpment descent, for a very short period of time. Often? ...I doubt it.

What kind of drag numbers do you gain without the FD? I raced on the US PRO TT course (not as part of US PRO) and with a 52-36/11-25 I never needed to go small ring but it was not flat, so what did I give up there?

Strava page
http://www.strava.com/segments/7281305?filter=overall

I didn't just take off the FD, there are no shifting components whatsoever. I'd expect 200-370g less drag without these items on an optimally designed "gearless" frame.

-SD

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https://www.kickstarter.com/...bike-for-the-new-era

Racing? Yes. Rev3 Knoxville 3 weeks ago I spent 8 minutes of the 1:07 bike split (Oly) below 20RPM or above 110RPM. I'd say 12% of a bike split is often.

That said the large gaps between cog sizes is the real issue.

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Rodney
TrainingPeaks | Altra Running | RAD Roller
http://www.goinglong.ca

I'll let it go (after this)... If you spent a whole 8 minutes going up and down hills, the majority of that '8 minutes' would have been spent going up hill. Especially with time spent peddling at 20rpm! So no, you were not spending 12% of your race going downhill and spinning out.

I apologize for picking on you. You just caught one of my pet-peeves after a long night of work. I'll stop now;).

I was thinking the same thing - impossible to "spin out" a 52X11 unless you pedal along at a cadence of 40 and 80 feels like you are spinning out....

I must admit, I ran the numbers and an 11-32 with a 50T chainring would work just fine this weekend at Kansas 70.3. And if you comfortable mashing up the climbs for a minute or so, an 11-28 would work too. On flat courses, you could go to a 12-25 with a 52T chainring. Interesting. Now I'd need a new

However, then there's very hilly courses at IM pace. I guess there's the 11-36 with maybe a 48T, but the gear spacing would get pretty large. But if it's constantly rolling, maybe that's not a big deal. Just a matter of adapting to riding a wider RPM range I suppose.

This is intriguing. Yes I'm the same guy arguing against a compact, but that's just an argument in gear ratio ranges only, in this case there are additional benefits.


Plus you could mess with people. You could simply remove the left shift lever on your extension, but leave the body there... and people would be like "dude, you shifter is broken".... and you could say "oh shit, that's not good. I guess I'll just go without it".


Spining out a 52x11?... what's that 45mph at 105RPM.

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TrainingBible Coaching
http://www.trainingbible.com

N = 1, I wouldn't do it. Even living in the midwest, there are enough hilly rides and races that I do which require multiple chainrings. So far this year, I have done rides/races and used every bit of 53/38 and 11-28, and I'm doing a ride next weekend that will be best with 52/36 and 11-32. I don't want the huge gear jumps of an 11-36 or super-wide 10-42 (or whatever the new SRAM 1x11 MTB stuff is) for road. If I was a big CX racer, I would think about doing it, mostly because the overall speed range on a CX course tends to be much narrower than road riding, and FDs can get mucked up with mud. And it's one less cable to replace.

Clearly 1x systems will work for some folks in road applications (such as folks racing/training exclusively in Texas or Florida, and are on the fitter end of the spectrum), but I don't see it being an overall 'plus' for the lion's share of the market, given all of the considerations/factors involved. Even with two-chainring systems, a lot of people complain about missing a 16t cog (or whatever their cog of choice is) - taking away rings in favor of larger cassettes only makes the problem worse.

LOL NO worries, I know what the data says and I know what I rode. I missed the podium by a minute and analyzed the crap out of that race :) And there are no hills in Knoxville that require you to go below 60RPM :)

I think there are some courses (Welland for one) where a single chainring 46t with 11x32 would suffice but dropping 3-4 teeth per shift is far too much for me on a hilly course.

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Rodney
TrainingPeaks | Altra Running | RAD Roller
http://www.goinglong.ca

That is what I'm using, a 55T, and I'd quite like to increase to 58T. How many teeth does yours have? I suspect the problem of dropping the chain increases significantly with each extra tooth.

I've done Welland. It's the 'Florida of the north' kind of flat course. I don't think I ever 'had' to get out of my aerobars, let alone shift down from my 50T chainring. It would be a good course for a single chainring set up. ... Speaking of that (and to get this back on topic), I just finished a winter 'project bike' and currently have it set up with a single ring up front. The bike is fun to ride! As it relates to Welland: My buddy took one look and said, "Can I use this at Welland?!" (he's doing the bike portion of a relay).

It's a 90's beam bike that was made in Germany. I originally built it up without a FD, but the chain skipped off in my first ride and I realized that I had to come up with some kind of a chain guide solution. So, I have it set up with a DA 7900 front derailleur as a chain guide. I chose this FD because it's designed to be wide enough that you don't have to do any trim adjustment (that... and I already had one). Of course, I can always add front shifting back on if need be.







(re 11-32 cassette)
Keep in mind that just because you've got an 11-32 cassette doesn't mean that you're dropping 3-4 teeth per shift. It's mostly 2 teeth between shifts, except at the easy end. Having said that, I tend to prefer a 50T chainring as it keeps me in the lower end (11-17t) of my cassette with only 1 tooth between shifts. Heck, on a flat TT out here, I just use a straight-block 12-23 and never run out of gears.

Yeah I pre-rode Welland last week and rode aero 99% of the time (outside of some corners and to stretch on "the downhill") and might have used 3-4 different gears :) I bet you could ride a good bike split on a properly geared single speed!

I do like the build you posted, I always love seeing beam bikes. Now that is something that should catch on more!

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Rodney
TrainingPeaks | Altra Running | RAD Roller
http://www.goinglong.ca

Very odd - normal 10 speed chain and cassette? It's just that you're the first person I've come across who has been able to use one without anything to keep the chain on and hasn't had it come off occasionally, so I'd like to know what is different about your setup.

I completely understand your perspective. There defintiely is a compromise going to a 46T Chainring and wide ratio 11/36 Cassette, but for me in an area with super hilly terrain that requires constant shifting loosing the front derailluer and the big cadence swing from 50T to 34T on a compact double is worth it.

For perspective I did some math last night for a 700c Wheel:

52/11 gearing @ 110 cadence = 40.40 mph (so you are really hauling ass!)
52/11 gearing @ 100 cadence = 36.73 mph
46/11 gearing @ 110 cadence = 35.72 mph (I don't spend much time pedaling faster than this)
46/11 gearing @ 100 cadence = 32.48 mph

For the Terrain around Bloomington, IN I'm typically either going sub 20mph uphill (sometimes as low as 4mph - Boltinghouse Hill is killer!) or coasting 40mph+ downhill (50mph down Boltinghouse for example) so the perfect shifting with wider gaps works well.
I'll be using Single Chainring in Ironman Muncie 70.3 in July (I've done this race 17 times) so we'll see how it goes - that course is gentle rollers so tighter spacing is good, but not big enough deal for me to convert my Titanflex back to double. Easier to just put my Red 11/28 cassette on the bike for that race (which I may just do)

Peace!

If I had small feet I would go through the trouble of getting 11 speed, and building a small q factor single ring setup.

But as it is my feet would just hit the chain stays.

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Kat Hunter reports on the San Dimas Stage Race from inside the GC winning team
Aeroweenie.com -Compendium of Aero Data and Knowledge
Freelance sports & outdoors writer Kathryn Hunter

Sure are a lot of PRO Mountainbikers winning races today with the new dedicated Single Chainring SRAM XX1 system on super rugged terrain... I suspect your comment is out of date and was pre- Wide/Narrow chainring design which has taller teeth and altering width of teeth to lock the chain on the chainring.

I'm sure we'll soon see lots of cyclocross races won on SRAM's new CX1 single chainring system.

I'm hoping SRAM invents a road version of the SRAM XX1 parts with a 50T chainring - I'll be first in line!

50T with a 10/42 cassette or 10/40 cassette would be awesome for Hilly Terrain (40mph top end and compact gear ratio climbing all without a front derailluer - sign me up!)

Cool Ride! (this from a fellow Beam Bike Lover!)

Here is a pic of the Wide/Narrow Chainring Teeth... look close and you'll see the teeth alternate in width from wide to narrow to wide to narrow which helps lock the chain on. Also see in the second pic the teeth on the dedicated single ring are much taller than a normal chainring. Cool Stuff!

Quick check in now that I have over 100 miles on my Titanflex with single chainring. Reminder - I'm currently running a WolfTooth components 44T wide/narrow chainring with a SRAM XX 11-36 cassette (10spd) and SRAM XX rear derailleur. Bike is functioning perfect. Not a single dropped chain on lots of rough pavement and steep climbs. So NICE not have to deal with a front derailleur! So far so good with the 44T front chainring without needing bigger for more speed - I was thinking I would want to get a 46T SRAM CX-1 chainring when available, but I think I'm happy with the 44T I'm using. I've found I'm able to add pedal torque at 38 mph downhill so I think I'm good with this setup... Hit 50.3 mph (coasting) down Boltinghouse Hill this weekend - ride recap pic below :)

Used my Titanflex with single chainring (44t wide/narrow chainring & SRAM XX 11-36 cassette) in Ironman Muncie 70.3 yesterday. Everything worked flawless for 56 miles at an average pace of 21.17mph. Course was windy with constant gentle rollers - basically 18mph uphill and 24+ downhill. A few sections downhill with a tailwind at 31mph. All in all another great bike course at Ironman Muncie 70.3 (much much better than last years course!).

The wide ratio rear SRAM XX cassette 11-12-14-16-18-21-24-28-32-36 (208 grams) worked well - I thought about using my SRAM Red 11-28 cassette with tighter spacing for the race 11-12-13-14-15-17-19-22-25-28 (158 grams) , but I decided to not mess with it and just go with my hilly terrain cassette since I was not going for a PR in this race.

Next year I'll probably swap out cassettes for the race since the terrain is gentle rollers. I only used 11 thru 18 cogs in the race so I could have saved 50 grams (0.11 lbs) and had tighter spacing for slightly improved efficiency with the 11-28 Red cassette.

Bottom Line - I'm not going back to a front derailleur (and see no need for heavier double derailleur electronic shifting as a result)!!!!!

Yeah I am also into 1x setups and agree that this basically eliminates the biggest advantage of electronic shifting. Wife has Ultegra Di2 10 speed and it really is magical in the front.

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/kj

http://kjmcawesome.tumblr.com/

Anyone seen any efficency data on the wide/narrow chainrings compared to the standard tooth profiles? When I put a Wolf Tooth 32T chain ring on my MTB bike I felt that there was a perceptible increase in friction. Could be just dirt and shiz in the drivetrain though.

I don't think the experiences with a 10t cog (or smaller) on the road have been positive.
-SD

Sweet ride! I love the steel frame with the curved top tube. Do you race it?

I agree Di2 is pretty sweet, but the cost, weight, and complexity are overcome via the simplicity and feather weight of the single chainring solution for me. I am very intrigued by SRAM's forthcoming wireless electronic shifting. That would be sweet with a single ring up front and wireless shifting in the rear, but I doubt it will be compatible with 11-36 cassettes or bigger.

My dream component set would be a road version of SRAM XX1 10-42 11 speed cassette with a single chainring and wireless electronic rear shifting (absolutely no front derailleur!)

Can do that set up mechanical right now. You just need the special driver that accommodates a 10t cog. 11 speed right lever and the naked left brake lever. 46t front narrow/wide chainring and you're good to go!

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/kj

http://kjmcawesome.tumblr.com/

SRAM's 11 speed road shifters (exact actuation) don't play with the XX1 mountain bike rear derailleur (x-actuation) which is necessary to use the 10-42cassette. I've tried using a 42T cog conversion on a shimano 11-36 cassette but the required B-tension adjustment with a regular long cage derailluer is too much for nice shifting in my experience - it works but not great...

The best way you can use SRAM XX1 on a triathlon bike setup is to use the XX1 11 speed grip shifter on the aerobar. Place the grip shift behind your hand on the aerobar so that your hand is in front of the shifter - see pics below. I used this setup with much success in the past with a temporary TRI bike I assembled from spare parts laying around and a cheap Leader frame... I may convert to the SRAM XX1 parts on my Titanflex in the future using the grip shifter on the aerobar, but the current setup is working so well for now I'll stick with it for some time!

Here is my second single chainring bike (I own the Titanflex in above pics too). It's a Giant TCX Advanced 1 Cross bike that I converted to single chainring with a 44T Wolf Tooth Chainring up front and SRAM XX 10 speed 11-36T cassette and Derailleur. Did an epic 43 mile, very hilly gravel road ride today and everything worked flawless! I upgraded the wheels, tires and crank in the conversion too...

Stock Bike (size XL) weighed 19.82 lbs,
Bike as in Pic is 16.91 lbs (not bad for Hydraulic Disc Brakes and Cross Tires!)