Aaah, why the fixed gear? Well, Bob is right as to the advantage of gears.
Humans aren't torque monsters. Our torque curve peaks at high revs. If one powers too much at low revs all you do is eventually blow out your knees. Ideally we should be spinning at about ninety rpm. That's much faster than most people spin when they ride but watch a road race like the Tour de France on TV and you'll see that even in the peloton just cruising along they're spinning quite fast. Ride much and you'll find that a fast spin is much more efficient and less fatiguing. And, as Bob says, gears allow us to maintain that spin under virtually any situation: uphill, downhill and on flats. So why a fixed gear? Well, for one thing, the single speed is set so that we are at optimal spinning speed while doing a fast cruise. So for me I might be spinning at 90 rpm while doing about 40 km/h. I could spin faster and hit 50 km/h on a flat road, faster yet on a slope. Going uphill is more work, but I think that one is actually forced to go faster than a geared bike spinning in a slow gear. It's actually harder going down hill because you're spinning like crazy trying to stay still in the saddle and maintain control. Since Toronto doesn't really have many steep or long hills we can just power up the ones we have for a few minutes. Couriers do not use fixies in San Fran, for instance. The fixed gear means there is no freewheel; no coasting ever. It makes you very manoueverable in traffic because you can accelerate much faster if your legs are always moving. Trackbikes have more vertical geometry and shorter wheelbases which makes them very maneoverable in traffic (at the expense of stability in high speed turns). Stopping requires technique as much as brute force. Move your body way forward to unload weight from the back wheel and you can lock up and skid. I tried not doing that except in dire circumstances. Simply anticipating traffic and not putting yourself in sketchy situations reduces the need for panic stops. That way simply slowing the pedals slows the bike, just like a kid's tricycle. Your stopping distances are longer but as long as you ride accordingly you're okay. Or you could add a front brake, but that ain't cool (even though probably smart). Trackbikes are lighter, sturdier and simpler and cheaper to maintain. All that being said, I now ride a road bike (gears and brakes) due mainly to my commute from New Toronto to downtown which adds maybe 15 - 20 kilometres to my daily riding. That and my advancing years mean that I need to conserve energy. Besides, I now think that what I lose in "quickness" is made up for with higher top speed and speed going down hills. So that's why a trackbike. Thanks for the kind words about the photo. And thanks for all the other comments and to those who looked. Glad you all liked! cheers, frank --- Original Message --- From: Bruce Walker <[email protected]> Sent: November 3, 2012 11/3/12 To: "Pentax-Discuss Mail List" <[email protected]> Subject: Re: PESO - Yuriy Yes, nailed it, Frank. Crisp and contrasty courier and subtly blurred bg. Nice! Since you mentioned speed and all: question. I though that the height of bicycle techno-efficiency was reached with the addition of multiple gears. So what's the deal with fixies? Does simple brute force win the day? I mean, bike/leg-power is most efficient within a range of rotations per minute, so the gears optimize the coupling there. With the fixie you must be standing off your seat at low speeds and reducing your spinning legs to invisibility at high speeds. WTF? On Fri, Nov 2, 2012 at 11:21 PM, [email protected] <[email protected]> wrote: > I know I've been posting a lot of bike messenger pix of late but when I see > one of my buddies zipping by it's hard not to snap. > > I kind of feel like I really nailed this one. It's pretty much full frame > (trimmed a teensy bit off the left to get him a bit more off-centre). Here's > Yuriy: > > http://knarfinthecity.blogspot.ca/2012/11/juri.html?m=0 > > As you can see he's one of those crazy trackbike-with-no-brakes guys. He's > real fast: routinely finishes top five in our local messenger races. > > Hope you enjoy. Comments welcome. > > Cheers, > frank > > "If the world were clear, art would not exist." -- Albert Camus > -- > PDML Pentax-Discuss Mail List > [email protected] > http://pdml.net/mailman/listinfo/pdml_pdml.net > to UNSUBSCRIBE from the PDML, please visit the link directly above and follow > the directions. -- -bmw -- PDML Pentax-Discuss Mail List [email protected] http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions. -- PDML Pentax-Discuss Mail List [email protected] http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
