Tuesday 11 May 2010

Optimised for long-distance commuting

Out of the garage today came another of my bikes, the fifth and last of my bicycles to be introduced to you on this blog. This bike was designed by me for long distance urban commuting in London in the early 1990s. Built by frame-builder Pete White at Ealing Cycles, this bike is optimised for stop-start traffic, safe yet fast riding through city streets.

The geometry is tight - short wheelbase, like on a criterium racer. Short chainstays, short rake on the front fork (one feels every bump!), steep frame angles. Slightly raised bottom bracket and shorter cranks so as to avoid the risk of a pedal hitting the ground on a tight corner. The frame itself is made from Reynolds 531 alloy tubing, a good compromise between strength, lightness and being easy to fix if broken. Yet the riding position is upright, not crouched, like on a racing bike. This allows optimal visibility. To see what's behind you, merely turn your head, you don't have to look under your armpit. And being more upright, I'm more visible in traffic. There is an aerodynamic penalty here; it took me three minutes longer to get to work on this bike today than on my Holdsworth racer yesterday (42 mins v. 39 mins). Still, I feel much safer.

Handlebars are shortened by 5cm on both sides to reduce the risk of clipping vehicles. Bright yellow, it's meant to be seen. Badge of pride: A London Cycling Campaign membership sticker with 071 area code phone number (pre-1995). Hub gears (Shimano Nexus seven-speed) allow for gear changes while stationary at traffic lights. In urban traffic, lights can catch you out leaving those with derailleur gears to have to get going in a high gear. The hubs also contain the brakes. This means a) improved braking efficiency (slowing the centre of the wheel rather than its circumference) and b) better braking in the rain (wet rims don't respond as well to wet brake blocks as the sealed hub brake). Mudguards are off for summer, they are full-length and close-fitting.

Drawbacks? Warsaw's roads are not as smooth as London's. This is the result of far greater temperature variations between winter and summer; frosts tend to break up road surfaces, which at the same time need to be able to withstand +40C heat. The ideal Warsaw fast commuter bike should at least have front suspension, and a sprung mattress saddle for comfort. This is a bike with just one use. It's no good off-road (the tyres are narrow, pumped up hard for low rolling resistance, but hopeless in soft sand). It's no good touring (there's only one position for the arms). But for urban journeys of 10-20km, it's as close as you can get to optimal.


Above: Holdsworth Triath-Elan, optimised for fast one-day touring and covering ground, though not so hot in urban stop-start traffic.

Right: optimised for multimodal, shorter distance all-weather commuting, the Brompton. Plus it's as chic as a MINI; heaps of style and cachet. Folds and unfolds faster and smaller than lesser fold-up bikes.

Below: optimised for uncompromising purity: my home-built fixed-wheel bike, for blasting up to the end of ul. Trombity and back. Good for winter training too.

Below: if there's one bike that's near universal for Polish conditions, it's a decent mountainbike. Nowadays, they come in a variety of flavours - DH (downhill) - full suspension for hardcore mountain descents. Too heavy for most other types of riding. XC (cross country) is the best all-rounder. My 2007 Cannondale Caffeine F2 has served me well for long rides, urban commuting and just pootling around local byways while whistling show-tunes. If you want but one bike, this is the sort to opt for.

2 comments:

Neighbour said...

Michael,

For your Yellow Arrow :-)

http://www.cyklotur.com/x_C_Sz2__T_OPONA+BIG+APPLE.html?PT=53024847&PZTA=8&HNT=T&PD=53010636&WSZDZ=T

This substitutes the "amorek"

I have such tyres in my mountain bike, it really works.

Please check if there's enough distance between the tyre and short tube reinforcing rear triangle tubes close to the bottom bracket and above the tyre on tubes running to the seat post.

You will be satisfied. Cyklotur IS RELIABLE.

Best regards,

Michael Dembinski said...

Hi Neighbour - those Schwalbe Big Apple tyres look the business. Only trouble is they are too fat for the front fork. (Rear triangle will accommodate). Front fork is real tight - 5mm clearance on either side of the tyre. A new front fork would need to be built to order, as it has braze-ons for the hub brake.