The English Mountain Bike

December 13, 2010 10:29 AM

Geoff Apps has been building and riding his own distinctive cross country cycles since the late 1960s. Unlike the members of the Rough Stuff Fellowship, who traditionally used touring or road bikes, Geoff's designs come from his background in motorbike trials (previously). After more than twenty years off the market, his latest design will soon go into production: the Cleland AventuraTT.
posted by scruss (17 comments total)

That looks totally badass, but the drivetrain is making me scratch my head.

Now, I actually use Biopace chainrings on a fixed-geared bike, and have a S3X hub to lace into a wheel this winter. But I still think that the Aventura's drivetrain is freakish. The combination of an extremely elliptical chainring, an inboard chainguard, and a high-spec tensioner make me wonder what the point was.

Still, this has a pedigree and the designer's credentials are established (I'm lusting after a Range Rider now, and I've only ever seen a picture). As wack as it is, I'd love to try it.
posted by ardgedee at 10:44 AM on December 13, 2010

... is making me scratch my head.

I had a bunch of those moments. There are a bunch of little touches that show the love and genius behind the design, but there are an equal number that make me wonder what the hell the designer was thinking.

But then, that's probably why I'm not a bike designer and he is.
posted by lekvar at 10:51 AM on December 13, 2010

The Aventura, with its high bottom bracket and short wheelbase, reminds me a little of old singletrack-specific mountain bikes like the Grove Innovations Hardcore and the Cannondale Beast of the East.
posted by box at 11:24 AM on December 13, 2010

Yeah, I'm torn between genius and madness. Although I like a lot of his older bike designs a lot.
posted by GuyZero at 11:33 AM on December 13, 2010

Can someone with knowledge/experience comment on the high center-of-gravity=maneuverability theory? I'm wondering if it's actually necessary on a bicycle that weighs a fraction of what a motorcycle tips the scales at.

Even with his "ride all day" reasoning, those bikes don't look like they make for an efficient pedaling position. Road racers aren't hunched over and stretched out just for aerodynamic purposes.
posted by strange chain at 11:41 AM on December 13, 2010

durrrr, "someone with trials knowledge/experience", that is.
posted by strange chain at 11:42 AM on December 13, 2010

> Even with his "ride all day" reasoning, those bikes don't look like they make for an efficient pedaling position.

An upright-ish posture is more comfortable, because it puts more body weight on the butt than the hands. Whatever you lose in raw calculable efficiency, you gain by being able to stay in the saddle longer before having to shake off the discomfort.

Cyclotourists and x-country off-roaders are optimizing for distance and haulage, not speed, so while wind resistance is always a design issue, it's not as overriding a factor as it is for competition race bikes.

I don't know how well the Cleland meets these goals, but those are some of the general principles. Sheldon Brown's site has some useful knowledge with regards to posture for riders who aren't road racers, and it's worth reading.
posted by ardgedee at 11:53 AM on December 13, 2010

> old singletrack-specific mountain bikes

I was originally going to post about UK-designed bikes, but Geoff's designs are the most radical. Back in the mid-80s, UK bikes had absurd BB heights and huge clearances to deal with mud and rocks. This 1988 Overbury's Pioneer was fairly typical; I seem to remember they used over-width tandem BB shells to get short stays and large clearances.
posted by scruss at 12:28 PM on December 13, 2010

An upright-ish posture is more comfortable, because it puts more body weight on the butt than the hands.

I ride in a position similar to a pro on the road (and off) with much of my upper body weight slung forward. At the end of a long ride, it's still my ass that hurts and not my arms. This looks like an extremely inefficient position with no trade off in comfort for serious riders but I haven't tried it so I can't say.
posted by klanawa at 12:48 PM on December 13, 2010

An upright-ish posture is more comfortable, because it puts more body weight on the butt than the hands. Whatever you lose in raw calculable efficiency, you gain by being able to stay in the saddle longer before having to shake off the discomfort.

That doesn't ring correct to me. An upright position puts your weight on the tender areas and makes it more difficult for your sitbones to bear your weight. An upright position means that since you extend your leg, you can't actually bear much weight on your butt. I wouldn't want to spend all day on my perineum.

Either way, if you're putting too much weight on your butt or your hands, you're doing it wrong. Weight's supposed to be bourne by the feet and the pedals.

Also, re: center of gravity - It looks like that bike is designed for a fairly low COG - those dropped-pedals look like they're designed to keep it low despite a high bottom bracket (which is for obstacle clearance).
posted by entropone at 1:30 PM on December 13, 2010

The description of the terrain the bike is designed for is pure poetry:

deep heavy clay with the constant passage of horses combines with wet chalk to produce a very uneven surface consistency akin to deep half-set cement mixed with the finest axle-grease. Water-filled ruts, slimy logs buried under wet leaf-litter, tree stumps and fallen boughs; tight, narrow bends with unexpected steep climbs and descents are typical.

[emphasis added], but I have to disagree with "this kind of going is commonplace in the UK, whereas California, the home of the mountain bike, could not be more different."

While all the downhill racing in Fairfax, CA in Klunkerz looked like it was done in the "dry" season, some mountain bikers with more than one gear ratio who ride uphill too avoid the heat & dust of the summer and prefer the cool air and challenge of winter mud.

I'm not one of those, but I did manage to run into some serious mud, hidden by a dried-over crust on top on a levee trail.

The hub gears make a *lot* of sense for "Its ethos is rather to keep going, whatever the terrain or difficulty of the conditions. " If you run into a bog at speed, you're going to need to shift to a lower ratio trying to get through it.
posted by morganw at 1:35 PM on December 13, 2010

One of the benefits of an upright position is that you can see the road way ahead without having to twist your neck and eyes as high as they'll go. Touring unknown roads and going cross country, one has to look far ahead and sideways a lot more often than when riding in road races.

For me, when riding in a "pro" road racer position in non road race conditions, the first thing that hurts is the neck from all the looking up and sideways, followed by the ass and then general muscle pain.

I ride long distances, with my handlebars higher than my saddle by several inches. I must be using some kind of anti-gravity leather saddle, because most of my weight is on my legs, followed by my arms and sit-bones. I can even lean back and put most of my weight on the sit-bone shaped depressions in the saddle without any perineum pressure.

I also love the use of hub gear. I am sure it takes 15 mintes to hose this bike off after a ride as opposed to 2 hours of picking twisted blades of grass cemented by mud between the cogs.

The height and position of the bottom bracket looks really interesting, I'd like to ride one of these bikes and see how it feels. My CX bike with the slightly elevated BB feels like it takes corners through hyperspace compared with my touring one.
posted by Dr. Curare at 2:13 PM on December 13, 2010

I ride in a position similar to a pro on the road (and off) with much of my upper body weight slung forward. At the end of a long ride, it's still my ass that hurts and not my arms. This looks like an extremely inefficient position with no trade off in comfort for serious riders but I haven't tried it so I can't say.

As someone who's ridden Very Long Miles in an upright position, you're forgetting touring bikes are not optimized for day rides, but weeks, months and years. Your arms can take the weight fine, but your wrists are where things can start to hurt.

Having an upright position also gives you a better field of view, since you're going to be plunking along at less than race speeds, one of the reasons you want to tour is to enjoy what it is you're touring *through*.

That doesn't ring correct to me. An upright position puts your weight on the tender areas and makes it more difficult for your sitbones to bear your weight. An upright position means that since you extend your leg, you can't actually bear much weight on your butt. I wouldn't want to spend all day on my perineum.


Not if you have the right saddle (for you) in the right position (for you). It's very very very comfortable. To give you an idea, the saddle on the road bike tips slightly (ever so) down, is fairly narrow, has a cutout in the middle - your standard road-bike fair. It works well and was fitted by a sports doctor.

My touring bike has a big ol' saddle (not naming brands), not as narrow, no cut out and is tipped quite a bit far up. Takes my sit bones, perfectly, no weird pressure, anywhere else. Miles and miles. Countries and countries.
posted by alex_skazat at 4:37 PM on December 13, 2010

Mr. Apps's bike has sort of a similarity to one of those comfort bikes, just... hardened. I think if you're going offroad for a few thousand miles, it would be fine. I'm a little perplexed at his idea of using trials motorbikes as inspiration, but whatevs.

I think, though, that crazy people, take all sorts of crazy things they call the perfect bicycle, on crazy adventures of crazy mileages and to each really, their own. I bet there's a website about it...
posted by alex_skazat at 4:41 PM on December 13, 2010

I'm not sure what exactly is raising questions about the drive train, but I've seen tensioner & internal hub combos at REI. I asked the salesman and the answer was simple: it makes it much easier to remove & replace the rear wheel than a tension free drive train.
posted by chairface at 10:31 AM on December 15, 2010

I think the AventuraTT uses a tensioner because it has an oval EGGring chainring. Plus, you really don't want your chain to think about going sideways under the chainstay. Quite a few hub geared bikes have tensioners; the BIXI/Boris Bikes have them.
posted by scruss at 5:56 AM on December 17, 2010

(Geoff's now responding to your comments here.)
posted by scruss at 5:15 AM on December 20, 2010