Begone, pesky and fragile derailleur!

July 18, 2005 9:51 PM

Huck This!
The internally geared GT IT-1 solves many a mountain biker's problems in one elegant way.
Also, not to be missed, the Rohloff SpeedHub 500/14, a 14 speed internally geared masterpiece.
Via
posted by fenriq (44 comments total)

Well, it's not jet packs, but it's definately a step in the right direction. Much like when automobiles advanced beyond the hemp rope drive.
posted by Balisong at 9:56 PM on July 18, 2005

nice! Thanks, fenriq.
posted by shoepal at 10:04 PM on July 18, 2005

*Drool*

Not that it matters because I'm more of a touring/road bike guy right now, but still.

Fun Fact: Much of the early car tech came from bikes, including planned obsolesence.
posted by drezdn at 10:05 PM on July 18, 2005

Cool cool!
I was checking out these a couple days ago - Dynamic "Shaft Drive" Bicycles (specifically this one).
Also, not quite the same, but "chainless" and cool nonetheless - Strida.
Thanks for the spiffy links!
posted by numlok at 10:10 PM on July 18, 2005

Look at how the bar slopes down... GIRLS BIKE!
posted by banished at 10:10 PM on July 18, 2005

Cool, I've been wondering for a decade when they'd get around to this. How about cramming CVT onto a bike?
posted by BrotherCaine at 10:14 PM on July 18, 2005

From the first link:
the IT-1 is durable and heavy, at 45 pounds

WTF?! At $5000 I'll definitely wait.

That Shimano one looks awesome. I hope the price goes down on that one soon.
posted by redteam at 10:30 PM on July 18, 2005

Yeah, but don't forget Sturmey Archer I did 15 years cycling in central London which would have been unimaginable without being able to change at the lights...
posted by marvin at 10:31 PM on July 18, 2005

It looks like they'd be a bitch to put together.
posted by bshort at 10:45 PM on July 18, 2005

I learned to ride on a Malvern Star Dragstar with three speed Sturmey Archer gears. After spending most of my cycling life with various high-maintenance derailleurs, the five-speed hub-gear Dutch bike I bought for commuting in Berlin was a joy to ride (complete with full length mudguards and a totally enclosed chain guard - no dust and crap in the chain, no grease and crap on my leg, no snow and mud up my back).

That said: my current road bike is a 21 speed derailleur with ratios from 26:28 to 54:12. I have yet to see a hub gear with that much range.
posted by flabdablet at 10:51 PM on July 18, 2005

Ok, so now I have! :)

Thanks, fenriq!
posted by flabdablet at 11:00 PM on July 18, 2005

That speedhub is supposed to be really nice. Put one on a BMW DH frame and you've got a bike that'll make that GT soil it's pants. I've been wondering who was going to be the first big bike maker to rip off the BMW drive train design.
posted by mexican at 11:06 PM on July 18, 2005

And before fixedgear gets here, the most elegant solution to the problem fenriq is describing has always been a fixed gear mountain bike.
posted by mexican at 11:21 PM on July 18, 2005

Nicolai have been locating a geared hub inside the frame for years. It's always been a spendy bike, and mostly only seen on racecourses. It's interesting to see GT bring this complexity to the market at a pretty reasonable price.
Mexican, I've seen a couple the BMW frames up here in Whistler lately, it's so cool to see a steel bike.
posted by tumble at 11:56 PM on July 18, 2005

In teresting, but as Marvin says, don't forget Sturmey Archer, my first gears and my fathers and I think my grandfathers.

Any idea why the Rohloff needs to be made in Germany?
posted by lerrup at 12:09 AM on July 19, 2005

Internally geared hubs are fine for cruisers and hybrids, but they will never make it into performance bicycles, whether on- or off-road. The fundamental problem is that humans generate little power but immense torque at low revs. In the hundred years of refinement that bicycles have experienced, no system surpasses the efficiency, light weight and robustness of the combination of derailleur & chain.
posted by randomstriker at 12:40 AM on July 19, 2005

There is a wonderful story where Bernhard Rohloff attempts to go for a ride on a sandy beach and gets the inspiration for his hub. It's in the catalog but it's not on the site as far as I can tell.

My hard core MTB workmate at the cycle shop where I work gave me it's pros and cons. There are the obvious pros like the "moving bits" being protected from the elements, and lesser known pros such as the 14 gears being equal in ratio to a 27 speed bicycle anyway (by eliminating all the overlap on a 3 front cog bike) and the fact that you lose weight by not needing an extra gear lever and front cogs.

He says the negatives are an overall weight gain and a weight distribution towards the rear. It is for this last reason that he said he'd never use a Rohloff. He's the ex-NZ trial champion and likes a light rear end to practice his craft.

Me, I'm not that leet and I'm saving up for one. Big bucks over here in Oz.
posted by uncanny hengeman at 2:26 AM on July 19, 2005

randomstriker: actually a track bike on the flat is the most efficent machine ever made.
posted by n9 at 4:13 AM on July 19, 2005

I'll keep that in mind, n9. I think I saw several consecutive meters of flat road, once, about two counties over from here.
posted by Wolfdog at 4:28 AM on July 19, 2005

I dunno... all that stuff on Dropin-TV just seems like a bunch of marketing driven wank to me, so I couldn't give a hoot about Hucking/Freeriding etc. (yeah like no-one was doing dropoffs 10 years or more ago).

Regarding the actual transmission, I'm kind of torn. Yeah rear mechs are very vulnerable but I've not had any serious issues in the past 13 years of riding. Does anyone know if these are easy to maintain by oneself? I resisted suspension forks, hydraulic disc brakes and even aluminium frames for a while due to a personal desire to be able to fix anything on my bike if I really neded to. In saying that I just bought a bike with all three of those things :)
posted by jackiemcghee at 5:33 AM on July 19, 2005

I'm torn too, I've ridden lots of miles in lots of different conditions, and have yet to have any trouble with my rear derailleur. There was that one time that I hit a Rottweiler and my derailleur seemed like it was messed up, but then after riding about 10 miles it was back in true. I love cool tech, though. Thanks for the links.
posted by OmieWise at 6:20 AM on July 19, 2005

Hub gears are the best. Heck, if it wasn't for dumb US import laws taxing bikes by weight, there'd be a lot more utility cycling on hub geared, hub braked, fully chain-and-mudguarded roadsters, like the entirely wonderful Dutch Gazelles.

It's a said day when MTB pioneer Joe Breeze says that perhaps the mountain bike wasn't a good thing for getting people riding bikes.
posted by scruss at 6:48 AM on July 19, 2005

It's a said day when MTB pioneer Joe Breeze says that perhaps the mountain bike wasn't a good thing for getting people riding bikes.
posted by scruss at 8:48 AM CST on July 19 [!]

Can you expand on this scruss? I'm not a bicyclist (my two wheels have a motor). Mountain biking sure seems popular though, is that not a good thing?
posted by Ynoxas at 7:04 AM on July 19, 2005

Wow, the Gazelles are well thought out, if heavy designs.

It seems here in the States your choice is either mountain or road bike, not enough of a choice for commuting, IMO. The hybrids tend to be softened up MTBs, rather than purpose-designed, and the cruizers are just too dang heavy.

Also, as a kid I had a Schwinn that had the Sturmey Archer gears. Built like a shit brickhouse, it was.
posted by SteveInMaine at 7:22 AM on July 19, 2005

Guess I should have Googled first. This place, for starters, has a decent selection of commuter bikes.
posted by SteveInMaine at 7:34 AM on July 19, 2005

i managed to snap off my rear derailleur while in the middle of nowhere (hit a rock at the side of the track). i didn't have another hanger with me (hell, there wasn't another in the country - i got one made by a guy with a file and too much free time that kept me going until i could import a few) and had to carry/walk the bike much of the way home (i got back just before nightfall, thankfully). i shortened the chain, but without a derailleur it kept jumping sprokets at the back, making it tricky to ride even on roads (no car, so cycled roads to track on the way out, meaning a long way home).

so yes, this seems nice. but why not put it in the rear wheel hub? i'm happy with a hardtail. i guess you can buy these and build your own wheel?
posted by andrew cooke at 7:40 AM on July 19, 2005

As a long time biker and motorcycler, I love the idea of moving the moving bits inside where they are much more difficult to mash and destroy. I loved my shaft drive motorcycle for its maintenance free nature and love this advance in cycling.

jackiemcghee, from what I read on the Rohloff site, they are maintenance free aside from a yearly oil change.

And yes, a sweet single is the most elegant solution until you get to a nice climb or big descent and then its shortcomings become apparent. But I have been absolutely dusted both up and down by single speed masters so that's only partially true.
posted by fenriq at 7:52 AM on July 19, 2005

That frame looks like a brooklyn machine works design. Also, I would not be too keen about the shimano hub.

As a mechanic, I've seen my fair share of S-A hubs. While not quite invincible (nothing is, really), they are quite fantastic, and easy to rebuild.
posted by chibikeandy at 7:59 AM on July 19, 2005

...one elegant, incredibly expensive way, yes...

Looks cool, though. Waiting for the economics of volume to kick in. T-10 years.
posted by RockCorpse at 8:05 AM on July 19, 2005

I'm a heavy, hamfisted rider, but I've learned to not shear my derailleur off in high weeds ( the hard way ). I've had no problems for at least a decade.

Technology can go a long way to solve problems, but so can technique.
posted by recurve at 8:49 AM on July 19, 2005

I'm just getting started biking, and my derailleurs go out of tune and whatnot pretty easily (I'm sure it's the low end, a friend of mine has a $100 walmart bike with the same ones). Not too much trouble though.

That said, for commutes, what about a foot-electric hybrid powered bike? How much energy would be lost converting energy into electricity and back?

I think an electronicaly-tuned drive that always offers the same resistance would be easier in the long run then a more efficent system.

But perhaps I'm on crack.
posted by delmoi at 9:58 AM on July 19, 2005

you really should have mentioned the crunchy guitar chords on the GT site...as a courtesy.
posted by Al_Truist at 10:19 AM on July 19, 2005

meanwhile, tullio campagnolo rolls over in his grave...
posted by RockyChrysler at 10:19 AM on July 19, 2005

Al-Truist, sorry, I had the volume on my computer turned off (sleeping baby) so I didn't notice any music on the GT site or I would have definitely dropped a warning.
posted by fenriq at 10:27 AM on July 19, 2005

fenriq: 'scool...my baby is (through no fault of gtbicycles) wide-awake and wiggly. :) ain't parenthood grand?
posted by Al_Truist at 10:41 AM on July 19, 2005

As I understand it there is another drawback to hub gear systems and that is that mechanical efficiency varies from gear to gear. It has to do with the different sets of internal gears that are engaged in some gears but not in others. So you might be more efficient in gears 1 and 4, less efficient in 2 and 4, etc.. This isn't necessarily a problem for commuting and utility riding but I wonder if one would notice it when performance riding. Anyone know more about this?
posted by Songdog at 10:46 AM on July 19, 2005

delmoi, I'm smoking a slightly different brand of crack, I was wondering both about the electric hybrid possibility, or some kind of pneumatic drive that circulates fluid through the frame itself. After seeing the internal shift hub, I'm wondering if there could be a way to vary gearing based upon RPM (using weights, springs and centripetal force to trigger shifting), and whether that would make an internally geared unicycle possible (definite crack smoking).
posted by BrotherCaine at 11:25 AM on July 19, 2005

Very cool fenriq.

I was looking into an SRAM DualDrive a few years back. It's basically an 9 speed cassette mated to a 3-speed hub. It seemed to me to be the best of both worlds:
-The efficiency of the rear derailleur without the unreliability of the front derailleur.
-The ability to shift while standing, without the complexity of a six or seven stage planetary gear system (as on the Rohloff & GT)

However SRAM is marketing it as a "comfort" product, so I have to wonder about its performance. Anyone have any experience?
posted by Popular Ethics at 12:34 PM on July 19, 2005

1. Without building tiny little rollers into every gear tooth, planetary gears cannot reach the same efficiency as derailleurs. This can be done, but I don't believe any bike product has ever done it.

2. The GT design is interesting, but adding a jackshaft, again, is an efficiency hit of something like 5%.

3. I don't think there's anything inherent about ratios creating different efficiencies in planetary gears. I know that the Shimano planetary hub created some gears by running the drive through two sets of ratios, thereby multiplying the efficiency loss.

4. As long as we're on the subject, check out Schlumpf's products--including the two-speed unicycle.

Because humans develop so little power, we really need every smidgen of efficiency we can get out of our bikes when performance is an issue. In short, I think planetary gears are an elegant idea, and make sense for commuter bikes, but until some major advances are made in engineering and material science, they're not going to catch on with performance bikes.
posted by adamrice at 4:52 PM on July 19, 2005

n9, let's not split hairs now. You're perfectly aware that I was discussing bikes with multiple gearing, even if I didn't mention so explicitly.
posted by randomstriker at 6:09 PM on July 19, 2005

Aren't recumbents supposed to be inherently more efficient than upright bikes? Something about being able to push against the seatback instead of your own weight, and being able to use full leg extension on the pedal downstroke? I don't know this from personal experience--I've never ridden one--but it stands to reason. Now, if somebody just makes one that a. doesn't cost stupid money and b. looks like a bitchin' chopper rather than a style-free dorkmobile...

Mind you, I'm pretty sure recumbents would suck ass for off-road use, and they're not allowed in Olympic or Tour de France-type competition.
posted by arto at 7:49 PM on July 19, 2005

Aren't recumbent supposed to be inherently more efficient than upright bikes?

No. Yes, you can push against the seat, but you're compressing a large amount of muscle tissue by sitting down on a seat -- and that's what makes power. (Note, humans don't generate much power, they need to get every bit they can.) Worse, a large amount of your muscle is holding your leg out -- a position your body isn't evolved to be in. On a regular bike, you're legs hold your body up, which is what they do. Power transfer is much more efficient on a diamond frame than a recumbent.

As to the full leg extension, if you aren't getting that on a diamond frame, your saddle is too low.

Why are all the ultra-speed bikes 'bents, then?

Simple. Drag. Over 20mph, the biggest factor slowing you down is air drag. Anybody who can walk a mile in under 20 minutes can bike at 15mph on a flat. Damn few can ride 30 mph on flat for any length of time, given no wind. Note how effective a tail wind is on your speed. Air drag is the dominant force in cycling about 20mph.

So, a recumbent on the Tour wins -- because you spend a very long time going very fast, fighting air drag, and the low, flat position of the rider is much more aero than the racer on a diamond frame.

Note the importance of pacelines and "lead out" riders on the Tour -- and how you are *not* allowed to draft, at all, in the time trail stages.

A 'bent can go much faster, because of the drag, but a diamond frame will accelerate much faster, because of the much more efficient power transfer. All the ultraspeed bike feature the same set up -- a very low recumbent, with a full fairing -- because every square inch facing the wind slows you down.

Note that the cyclist powered aircraft did *not* use recumbent seating, but upright saddles. There, the speeds were much lower (reducing drag), but power was critical. The pilot/motor had to generate X watts per minute of power, or the aircraft would stall and crash.
posted by eriko at 8:37 PM on July 19, 2005

Expensive (almost $1,000 USD) and heavy. I know, we're giving up front and rear derailers, cassette, two chainrings and one shifter but when one can buy a perfectly good complete 27 "speed" bike for $1,000 this will be only for the few.

So, a recumbent on the Tour wins -- because you spend a very long time going very fast, fighting air drag, and the low, flat position of the rider is much more aero than the racer on a diamond frame.

Note the importance of pacelines and "lead out" riders on the Tour -- and how you are *not* allowed to draft, at all, in the time trail stages.

The advantages gained in the TT stages (two this year) would lose out in the mountains. Recumbents are cool, but they are never gonna climb as fast as an upright bike.
posted by fixedgear at 3:36 AM on July 20, 2005

There is (or rather was) a bike with an transmission that shifts automatically based upon cadence, BrotherCaine. As I recall it uses the centifugal force of the rotating front ring(s) to control shifting, as you suggest (start pedalling slower and it shifts down, faster and it shifts up). The bike is called the AutoBike and the technology is called EasyShift, but I believe it is no longer in production. There are several other automatic bicycle transmission designs out there too.
posted by Songdog at 7:24 AM on July 22, 2005