View Full Version : touring bike geometry?
blehargh 06-26-2004, 09:32 PM is there such thing as a classic touring bike geometry? if so what would it be?
I'm interested in getting a commuting bike really that's actually fun to ride around on but can handle moderate touring. just trying to find a happy geometric medium that can handle both.
also just curious about people's views on disc brakes for touring also? specifically avid road mech's with STI levers..
thanks in advance.
-don
The Walrus 06-27-2004, 12:10 PM ...the angles on a true touring bike will be slacker than on a "conventional" road bike; you want stability rather than quick handling. Wheelbases will be longer, courtesy of the extended chainstays. A lot of touring frames are set up to give a more upright riding position; I know the last thing I'd want on a 60-70 mile day is being in an extreme aero position the whole distance. Note than none of this necessarily means a bike for loaded touring is going to be a slug. I don't ride crits on my old Novara Randonee (actually, I don't ride crits at all), but it's perfectly acceptable as a "sport" bike.
As for discs, there was a piece by Sheldon Brown in a recent issue of Adventure Cyclist addressing this; the gist of it was that the negative might slightly outweigh the positive. The good things about discs are the power, the weatherproof performance and the fact you won't be friction-heating your rims (and tubes/tires) on long descents. The bad things are that it can be more difficult to deal with removal/installation of wheels, especially when racks are mounted, and the front wheel will be somewhat weaker because of the dishing required to accommodate the rotor.
blehargh 06-27-2004, 05:33 PM hrm....
yeah i guess i'm worried that "relaxed" geometry will make the ride sluggish. but it'll probably be fine. i can always just use my regular road bike in that case.
how does having discs make installation of the wheel more difficult? it seems like it might be easy with discs since you don't have to worry about detaching the brakes?
yeah understand about the weaker front wheel. assuming it's built well, and having an offset spoke bed would help. after all rear wheels are uneven too and people tour on them all the time right?
-don
Frith 06-28-2004, 05:04 PM is perhaps what you're looking for. Not as aggressive as a road bike and not as sluggish as a touring bike. I was really after a Marinoni Ciclo to serve just this purpose. You can get one with for $700 canadian for the frame and for 1-200 extra custom geometry options and custom paint.
I ultimitely cheaped out and bought a $200 cx frame on ebay... but i still pine for the ciclo.
ps. There are others in the sport - touring range not many come to mind at the moment. I seem to recall one... there are a couple jeff lyons being sold at gvhbikes.com that seem to be a great value.
RUSA2392 06-29-2004, 05:33 PM mtbs are built to take the strain; the typical road fork is not.
is there such thing as a classic touring bike geometry? if so what would it be?
I'm interested in getting a commuting bike really that's actually fun to ride around on but can handle moderate touring. just trying to find a happy geometric medium that can handle both.
also just curious about people's views on disc brakes for touring also? specifically avid road mech's with STI levers..
thanks in advance.
-don
I run discs on my MTB and from riding that and a CX and road bike i can say you dont need discs on a road bike. On my CX bike i run full sized v brakes. You can find bikes with "canti" mounts that will allow you to use a ful sized v-brake. They work great but do require a different brake lever and therefoe restricts you from using STi. I'm using bar con shifters now that work well. Howver my next stpe is to mount the shifters on the tops of my bars using a pauls gadget that turns the bar cons into thumbies.
Fredrico 07-02-2004, 05:47 PM My commuter bike has a short wheelbase, 39", the same as a racing bike. That enables it to scribe tight curves in turns, and makes it handle quickly in urban traffic.
The bike also has long chainstays, 43 cm., about an inch longer than a racing bike. This puts the rear wheel furthur back, allowing for additional weight over the wheel, keeping most of it in front of the rear axle.
The frame has 73 degree parallel angles, making the steering "neutral" and predictable. Working the crank from a bit more saddle set-back encourages pushing at moderate cadences, the most economical pedaling method for all day in the saddle. The saddle set back is also "neutral." It allows satisfying spinning as well.
This might be what you're looking for, but there's a trade-off.
While the 39" wheel base preserves a nice handling ability, it puts too much of the rider's weight over the front wheel--unless a load is carried over the rear wheel. Classic touring bikes have 40-42" wheel bases, to keep fore-aft balance right. They have great straight line stability, but are unresponsive to turns. This directional stability is enhanced by slacker steering and seat tube angles, typically down to 72 or 71 degrees. That's pretty much what you want when loaded, straight line stability. The 42" wheelbase long distance tourers accomodate the carrying of weight over the front and rear wheels and still balance well, fore-aft.
The other desirable thing for a touring bike is to be strong enough to carry deadweight up to 100 pounds. Cantilever brakes are probably unnecessary on the road, but they always allow clearance for fenders. Side pull road brakes are more compact and out of the way, but the calipers have to be "long reach," working off a brake bridge positioned high enough on the seat stays to allow clearance for a fender.
Touring bikes also have threaded eyelets on the dropouts and seat stays to mount a rack and fenders. They're also mostly made of steel. Steel will take the punishment of endless miles of loaded riding better than aluminum or carbon fiber.
A good touring bike will also have generous drop handlebars, about the height of the saddle, with enough reach so the rider can move around, stretch, change hand positions easily, and stay relaxed on an all day ride.
My .02. Some things to think about, anyway.
Have fun with it!
RUSA2392 07-02-2004, 06:03 PM Also, I have cantilever brakes with STI shifters on my touring bike. They're very good, almost as good as the DA brakes on my road bike. I think the biggest difference is the pads, Kool Stops on the canti's and DA's on the DA's. However, the DA's do have more leverage. The levers feel firmer and they do stop better. The STI/cantis w kool stops brake better than the bike did when it was new 15 years ago.
blehargh 07-04-2004, 11:57 PM ya. i knwo you dont' need disc brakes on a road bike, but on a _touring_ bike? i don't want to give up the STI's and i'm not entirely enamoured with the canti's. plus i want this to be an "all weather" bike. rain, slush, whatever - discs would be nice for that slop.
-don
blehargh 07-04-2004, 11:57 PM mtbs are built to take the strain; the typical road fork is not.
just get a disc specific fork. easily done.
-don
blehargh 07-05-2004, 12:03 AM wow. that was detailed... thanks!
-don
Spinfinity 07-06-2004, 10:02 AM Any builder can make one but, in addition to Marinoni, Jeff Lyon, Steve Bilenky, Heron, Rivendell and probably lots of others have made them as a big part of their business for many years. Bruce Gordon makes some sporty, heavy duty touring bikes, too.
I'd pass on the disk brake, but you obviously want one, so you should get what you want.
Tire clearance is a major concern, especially if you're going to ride through snow and slush.
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