Prototype 9 - 36 tooth Cassette Gearing - First Look
Specialized team rider Curtis Keene dropped by Pinkbike HQ to sample our local trails and to give us a closer look at his very special carbon S-Works Enduro trail slayer. Why so special, you ask? It was equipped with a single ring and a prototype 9 - 36T spread, 10 speed cassette. Have a look inside for more photos and info on his steed and its gearing.
Are single ring and large spread cassettes the future of mountain bike drivetrains? Let the discussion begin inside...
Prototype 9 - 36T, 10 speed cassette gearing
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Gear development comparison*
• 32 tooth ring x 9 tooth cog = 7.662m
• 32 tooth ring x 36 tooth cog = 1.916m
• 32 tooth ring x 11 tooth cog = 6.269
• 22 tooth ring x 34 tooth cog = 1.394
*Gear development (also known as rollout) is the distance traveled by the bicycle per one revolution of the crank
Death to the front derailleur? Certainly not, although a lot of riders who currently run a double ring, traditional 22/32 combo can get very similar gearing by using the new 9 - 36T spread cassette with a single ring of their choice. Ditching the extra ring, front derailleur, shifter, and the associated cable and housing in exchange for the new cassette and a lightweight chain guide will not only be lighter overall, but also more reliable. The addition of the 9 tooth cog will allow you to reduce the size of your front chainring, thereby broadening your gearing range - something that going from 7 cogs to 9 cogs never achieved (more redundant gears were added). Not only is a wider range possible, but we could also see lower bottom bracket heights due to the extra ground clearance. The 9 - 36T spread is not yet available to the public, but I'm betting that it's only a matter of time until we see production versions released. Stay tuned!
Are we looking at the future of mountain bike drivetrains? Discuss below!
Are single ring and large spread cassettes the future of mountain bike drivetrains? Let the discussion begin inside...
Curtis Keene dropped by the Pinkbike HQ with his Specialized Enduro S Works Carbon that was equipped with the prototype 9 - 36 tooth spread, 10 speed cassette.
The last few seasons have seen the mountain bike drivetrain make what can only be described as a meteoric jump on the evolutionary ladder, especially when comparing its latest progress against the previous decade's worth of advancements. People have long been playing around with gearing combinations that suit their terrain, take many riders from B.C.'s North Shore region who have been running modified double chain ring cranksets since mountain biking's early days, but manufacturers are now stepping up to the plate more so than ever with options for everyone from single speeders to those who want just the right gearing spread for their local terrain and style. Just take a look at the super trick 1 x 6 gearing using a 9 tooth cog that you saw on the Team Monster Energy - Specialized bikes ridden by Brendan Fairclough and Sam Hill. Similarly, companies are also working on a large spread cassette, shown here for the first time, for XC use that also uses a 9 tooth cog on the high end.
The last few seasons have seen the mountain bike drivetrain make what can only be described as a meteoric jump on the evolutionary ladder, especially when comparing its latest progress against the previous decade's worth of advancements. People have long been playing around with gearing combinations that suit their terrain, take many riders from B.C.'s North Shore region who have been running modified double chain ring cranksets since mountain biking's early days, but manufacturers are now stepping up to the plate more so than ever with options for everyone from single speeders to those who want just the right gearing spread for their local terrain and style. Just take a look at the super trick 1 x 6 gearing using a 9 tooth cog that you saw on the Team Monster Energy - Specialized bikes ridden by Brendan Fairclough and Sam Hill. Similarly, companies are also working on a large spread cassette, shown here for the first time, for XC use that also uses a 9 tooth cog on the high end.
It's easy to spot the difference between the new large spread prototype cassette (shown above) and a standard version when looking from this angle.
The spread above uses a 36 tooth large cog on the low end and a tiny 9 tooth cog for the highest gear. This is where the ingenuity comes in, because as anyone who's had their cassette off may well know, the smallest cog that would previously fit would be an 11 tooth version due to the freehub's diameter. This is where DT Swiss steps in with a custom made freehub body that accepts a smaller cog. As of right now the actual design of the freehub remains unknown, but to get an idea of what it may look like, have a gander at Shimano's commuter intended Capreo group that also uses a 9 tooth small cog. I'm betting that the DT Swiss freehub is also stepped and that the bottom few cogs are a single unit. The very special freehub body has been manufactured by DT Swiss solely for the R & D that Specialized is doing for this project, you won't see it anywhere else anytime soon.
The spread above uses a 36 tooth large cog on the low end and a tiny 9 tooth cog for the highest gear. This is where the ingenuity comes in, because as anyone who's had their cassette off may well know, the smallest cog that would previously fit would be an 11 tooth version due to the freehub's diameter. This is where DT Swiss steps in with a custom made freehub body that accepts a smaller cog. As of right now the actual design of the freehub remains unknown, but to get an idea of what it may look like, have a gander at Shimano's commuter intended Capreo group that also uses a 9 tooth small cog. I'm betting that the DT Swiss freehub is also stepped and that the bottom few cogs are a single unit. The very special freehub body has been manufactured by DT Swiss solely for the R & D that Specialized is doing for this project, you won't see it anywhere else anytime soon.
The 9 tooth cog is held on with a large lock ring on this prototype version.
The new gearing range made possible by these large spread cassettes may not get the press that a new bike would, but this is big news for a lot of riders who want to simplify their drive train by running a single chain ring, but still want a usable gear selection. So what does all this talk mean? Well, the real story here is the addition of the 9 tooth cog to the mix. The 9 tooth cog allows the rider to use a single smaller chainring (say a 28 or 30 tooth ring) as opposed to a double ring setup to eliminate all of those redundant gearing options, but also even broaden the gearing range. For example, a common 24 tooth ring and 36 tooth cog combo gives you a rollout of 1.52 meters, but a 28 tooth ring and 36 tooth cog would give you 1.67 meters... a pretty damn close easy gear. But on the other end a standard 32/11 combo gives you a max rollout of 6.26 meters compared to a 28/9's 6.7 meters. At this point in time Specialized is the only company that is pursuing this gearing concept, but it makes enough sense that we could possibly see that change in the future.
The new gearing range made possible by these large spread cassettes may not get the press that a new bike would, but this is big news for a lot of riders who want to simplify their drive train by running a single chain ring, but still want a usable gear selection. So what does all this talk mean? Well, the real story here is the addition of the 9 tooth cog to the mix. The 9 tooth cog allows the rider to use a single smaller chainring (say a 28 or 30 tooth ring) as opposed to a double ring setup to eliminate all of those redundant gearing options, but also even broaden the gearing range. For example, a common 24 tooth ring and 36 tooth cog combo gives you a rollout of 1.52 meters, but a 28 tooth ring and 36 tooth cog would give you 1.67 meters... a pretty damn close easy gear. But on the other end a standard 32/11 combo gives you a max rollout of 6.26 meters compared to a 28/9's 6.7 meters. At this point in time Specialized is the only company that is pursuing this gearing concept, but it makes enough sense that we could possibly see that change in the future.
• 32 tooth ring x 9 tooth cog = 7.662m
• 32 tooth ring x 36 tooth cog = 1.916m
• 32 tooth ring x 11 tooth cog = 6.269
• 22 tooth ring x 34 tooth cog = 1.394
*Gear development (also known as rollout) is the distance traveled by the bicycle per one revolution of the crank
Death to the front derailleur? Certainly not, although a lot of riders who currently run a double ring, traditional 22/32 combo can get very similar gearing by using the new 9 - 36T spread cassette with a single ring of their choice. Ditching the extra ring, front derailleur, shifter, and the associated cable and housing in exchange for the new cassette and a lightweight chain guide will not only be lighter overall, but also more reliable. The addition of the 9 tooth cog will allow you to reduce the size of your front chainring, thereby broadening your gearing range - something that going from 7 cogs to 9 cogs never achieved (more redundant gears were added). Not only is a wider range possible, but we could also see lower bottom bracket heights due to the extra ground clearance. The 9 - 36T spread is not yet available to the public, but I'm betting that it's only a matter of time until we see production versions released. Stay tuned!
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Until a desent 11speed hub comes out with off road back up.
You don't need a very heavy bike that you can ride everywhere? AM wheels are used for DH, XC groupsets are used for AM/FR, XC wheels are used for AM. I am saving money for a AM bike that I am to weigh about 13kg (28.66lbs). With it I will be able to climb, go downhill and take some gaps. I know I won't be able to go extreme when it comes to FR, but if i wanted that I'd buy 2 different bikes. I am in a pickle about the crank setup, because most shiftable chainguides are not adapted to the new 2x10 chainlines and require some modifications.
The idea of a Hammerschmidt system is not a bad idea at all, although the weight is not very attractive. It's like those dropper seatposts, they come in very handy, but at a sacrifice of +/- 0.5kg (which is a lot).
I like what 2010 brought us, and I am convinced that 2011 will bring us even more nice and good stuff.
A 29 tooth ring and 9 tooth cog would give you roughly the same ratio (6.94m vs. 7.05m for your current setup), but more ground clearance and you'd be able to ditch the granny ring while also keeping roughly the same low ratio.
your paying an extra £150 for an extra cog which probably costs the manufacturer £0.50 to make.
That would be real progression, gearbox/hub-gears are the way to go if money and development were poured in to it.
I bet Shimano wouldnt like to see all the revenue for the mechs and cogs go missing.......
I would love to be able to run a 1 x 10 setup, but I run nothing but flat pedals and with all the climbing we do around here there is no way I could pedals up everything with that setup - that's unless I run a small front ring, but I also don't want to spin out on the descents. 1 x 10 is not for everyone, but if you can get away with it, it's a pretty sweet and clean setup.
I've been running a double ring with an MRP LRP for years now and never missed a shift nor dropped a chain - so I have no problem running a front derailleur. Also 10 spd can be a bit finicky to setup and maintain. like someone mentioned, a slight change in cable tension or a slightly bent derailleur hanger and your shifting goes out the door. Same will happen with 9spd setup, but it's not "as" bad.
i would love that in my enduro setup
I understand how xc guys would want more cogs, but as an all mountain guy I'm not very excited. I'd prefer a lower maintenance set up. A light and efficient internal 8 with belt drive and something like the hammerschmit but belt driven and lighter sounds like heaven to me.
I understand the concern over bent hangers and the 10 speed's tighter tolerances, but having been down that very road, it wasn't an issue for me. It seems to me that most bike's hangers are much more resilient than they were when we were running 7 cogs out back, or even when 8 was the common number. I believe that it is this fact, combined with the tighter tolerances and higher quality of modern derailleurs that makes this a non-issue... for me anyways. There will be those who bend hangers or damage derailleurs on a regular basis - those guys are maybe screwed whether they have 10, 9, or 8 cogs out back.
I'm with HTNDave - Internal gear hubs are the future, Shimano just won't accept that though and will continue to bring out hopeless ideas like 10 speed cos that's what they've always done and Sram will have to follow suit in order to compete. We are really pushing the whole derailleur idea way beyond it's limits.
Anyone know how long a Shimano 10 speed chain will last? I reckon I'd snap it on the first ride.......
Don't get me wrong, at times I miss having a big ring, and even though I rarely use a granny there are times when I would want one. But given the simplicity and reliability of a single front ring, I'll take it over a triple. I love using an xc/am bike with that set up plus a super light chain guide.
As often as I bend my hanger though I still think less is more for me.
Snap on the first ride?! Hardly... There are loads of riders out there with plenty of miles on Shimano, SRAM, Wipperman ect 10 speed chains and have had no issues. I've used all all of those options and have had no issues with chains snapping. 10 speed isn't new by any means, it's only new to mountain bikes. And I don't believe the argument about MTB's putting more stress on chains than road bikes.
The interesting bit here isn't the 36 tooth cog, but the 9 tooth cog on the opposite end.
What I'm getting at is that this system can eliminate the redundancy of current gearing setups. You get a gearing range that is very close, but with less fuss. Done correctly, you could increase your gearing range as well.
Smart jumps between the gears are vital for a lot of riders who are particular about their cadence, too big of jumps could be an issue. The cassette pictured though has been put together out of what was available and it's possible that it doesn't have the jumps that the average rider would want. If this ever does see production, which I hope it does, lets keep out fingers crossed that the jumps make sense.
Sram or KMC 8spd chain = $15
Old 83 gram Shimano top mount shifters... priceless
Wider gear spread, better chain line and chain-to-tire clearance when you space the cassette outboard with the extra room you made by not using the 11, flawless shifting under all conditions, and yes, with practice, front derailleurs work fine.
The only thing that scares me is the 44 tooth razor death circle pointed at my right calf.
One ring up front for simplicity would be nice.. no thought put into shifting and all, want harder.. just pick the next gear. NICE
This with a 30t front ring would give me everything I would want.
What I am not sure about.. 75% of my riding is done in granny gear.. (very steep short techy climbs, to coasting down short hills, repeat to exhaustion). Sooo grany ring on the front gives me the nicest chain line.. but would suck for the other end of the cassette. So i feel like for me chain line would suffer as I would have to compromise somewhere.
Also.. as is I am constantly double shifting. I'm not racing or going for the fastest time and perfect cadence means little to me, I'd rather slightly fewer option, less weight.
But I used 32t ring with 34-11 cassette all this summer and used both extremes off my gearing, and at times hoped for just a little bit more range (usually so i could just putter up some longer climbs). So I could see thing working out okay.. But straiter chains last longer and seem to feel better. So after a couple months I have switch back to dual ring front (24,36) and will probably try out a custom cut down cassette next summer. ( tinkering is fun!)
In closing.. I can see where this could work perfect for someone! And would love to try it and see how chains last for me. But I would rather a frame mounted internal transmission! Mounted low and central on a slack 6" bike for "AM" and make it belt driven to the rear.
32T / 11T = 2.91 ratio
22T / 32T = 0.69 ratio
26T / 9T = 2.89 ratio
26T / 36T = 0.72 ratio
All we need now is a crankset with a smaller BCD middle ring spider and voila! Goodbye Hammerschmidt, front derailleur/shifter/cable/chainsuck, etc.
For example, a 44x11 transmission has the same ratio as a 36x9 (4x). But to get a ratio comparable with 36x36 (1x) using a 44t ring up front, you would need a 44t ring in the back (44x44).
Getting the same shifting range as a 9-36 cassette would take a 11-44 one.
From my experience I know that a wide ratio cassette is a winner although the biggest cog has to be 39t to compensate for the old 22t granny.....
*I think that you could get away with a 22 or 24 chainring up front and that 9 tooth in the back.
Totally agree....
www.canyon.com/_uk/technology/project144-2.html
More "push" on the DH side!
cool for 7" allmountain bike with single chainring + guide
www.widgit.com.au
Less fuss as there is no front mech
Add a chain guide and you've got a much more secure chain.
Less noise.
And all the gears of 2x9 speed? YES PLEASE!