That my freind,
IS the fastest bike in the world. If I could afford one ($5k frame) it would be mine, well until January 1st 2007 I suppose.
They are very rare, distributed by
http://www.airointernational.com
I posted this a couple years back:
http://www.timetrial.org/lotus.htm Scott Godfrey's Custom 110Mk2 Lotus Sport TT
Lotus Sport Time Trial Bicycle The 'LotusSport' Pursuit Bicycle had its international debut at the 1992 Olympic Games in Barcelona. Chris Boardman won the gold medal for Great Britain in the Individual Pursuit event and set a new unofficial world record of 4.24.496 in the quarter finals, which represents an average speed of 56.54 kph over the 4000m.
The 'LotusSport' bicycle is derived from the Burrows 'Windcheetah', to which Lotus Engineering acquired the rights in February 1992. Since then, considerable design and development work has been carried out on the structure and shape to optimise the performance and minimise weight. The pursuit racer is the third generation design in as many months.
The heart of the design is an aerofoil section composite monocoque which is moulded of advanced materials, mainly carbon fibre. Lotus has considerable experience of working with such advanced materials, both for competition and general usage. The bike is designed to reach new levels of efficiency and low drag for improved performance.
Chainring This is the two sides of my "current" chainring. I started with a 50 tooth Stronglight ring and laminated the outer surface with a layer of 1oz kevlar cloth capturing a set of inverted and profiled chainring bolts within the structure.
The chainrign was then slipped over teh crankarm and placed against the crank spider while I bonded a lenticular shaped cover made of a single ply of 5oz carbon fiber on the inner side.
Bolts were then passed through the covering to secure the chainring in place.
Saddle The saddle bracket that accompanies the Lotus Sport is something quite ugly and leaves a lot to be desired.
It looks like an afterthought and from what I understand, it was an afterthought af the designers to make the bike rideable. For such a sleek bike, the bracket has a clumsy design incorporating a total of 10 bolts to hold the saddle in position where the typical seatpost has just two.
Unfortunately I don't have a photo of it yet, but here are several views of the integrated unit I redesigned.
Where all 10 bolts used were necessary to hold the saddle on [and I have had failures during critical events] I refined and finessed the design a bit and eliminated all 10 bolts by designing the saddle and the saddle bracket as a single non-adjustable component to fit exclusively my riding position and style.
Two bolts were added back, but are completely non-structural in nature, they're only there to keep the saddle down when I stand up to pedal. This configuration is incredibly light weight, sleek, rigid, and virtually maintainence free.
As you can see by the nose of the saddle, this is actaully based on a Selle Italia Flite saddle. An old saddle with no padding was used as the form and then improvements made from there.
Handlebars/brakes This is where the goods are at! Rebuilding my aero bars was actually my intent when I started composite fabrication this year, everythign else was the result of needing things to practice on and satisfying long time desires in soem cases just to make teh whole bike a bit more elegant. As can be seen in the iages above with the silver handlbars [ITM Dual Aero bars], although they're low profile and one of the aerodynamically fastest available, they're butt ugly. Brake cables sit in open air with no routing, the outboard grips are just bulbous and huge with no effort made for streamlining them. I wanted to clean up the airflow a bit and ended up achieving far more than I intended from the original dream.
The first component I actually made in this process was that little tailcone behind the bars above where it says Lotus. Good practice and a bad expereince, it will be replaced, but I thought I'd make the note.
The handlebars themselves went through all sorts of design changes in my head fro integration with standard brake levers to my own designed brake levers, cable routing in a number of ways, honeycomb or truss or hollow internals construction to what it is now- solid carbon with a thin balsa wood core. Many paragraphs of exchanges with two frineds in engineering regarding how to retain the structure with bolts only to arrive at the conclusion that bolts are not necessary to hold it together at all. it was an expereince and it's not quite done yet either. I still have no retention mechanism or padding for my arms, so riding them is quite "interesting" and actually very tiring. For their first event I took them without a finished surface just in case there was more work to do, but there is not. I just need to add arm rests and do the final shaping and finish coating.
The end result has been a handlebar with an incredibly thin profile and exceptionally clean presence. At the leading edge where thickness is consistent the bars are barely 1/3 inch thick and the brake levers go up near 1/2 inch. The component they have replaced was at its thinnest nearly a full inch thick.
Rear Derauiller As I was spending a lot of time learnign a lot of ins and outs of carbon work, I was also spendign a lot of time waiting. Once I got rolling in my production processes, the resin I was usign had a cure time of roughly 90 minutes. To keep things moving I would have to interleave a lot of processes or else I'd have a lot of dead time waiting for things to happen. One night I was looking around for potential improvements to make to occupy time and noticed the inside plate of my rear derauiller looked easy to replace [we're talkign real bored, isolated and lonely at this point people]. In no time I had cut up some scrap pieces of carbon cloth and had them prepped for my next pass through the wonderful world of epoxy.
Fabrication was real easy as I just saturated a bunch of carbon, stuck it together and sat a couple books on it for compression. The following day I removed it, trimemd it down to a similar profile as the "stock" component with a pair of scissors. Drilled both holes and tapped them to insure it would work, removed it, slapped a few more layers of carbon on it with compression for another night, did the shaping and drilling deal again and it was basically done. I dont' know if it's any lighter than the old component, but it's about half as thick and it's far less noisy than the old one that was full of cutouts. I doubt it matters since that region of airflowis nightmarish to start with, I list this part as simply novelty and the result of idle hands :)
Written by Scott Godfrey, introduction courtesy of Lotus Esprit World. Scott is a CAT 2 Track Racer, and one of the fastest CAT 3 Time Trialists in Southern California. Photos by Damon Rinard and Scott Godfrey.
http://www.lotusespritworld.co.uk/.../LotusSportBike.html
