Lightning Low Racers

(No longer in production.)

These may be the fastest unfaired bicycles in the world. They are custom-built for road and track racing, as well as bike path sprints. People do ride these on the street as well, but only outside cities on roads with wide shoulders, or with little traffic.

We start with the M-5 lowracer frame and seat built in the Netherlands by Bram Moens, then add many improved features, including:

• Special fork with a 406 front wheel eliminates crankarm/front wheel interference
• Custom modified twist shifters for quicker, faster, and more accurate shifting
• Shimano 105 components with wide gearing range
• Carbon headrest standard
• Shock cushioned seat mounting
• Front derailleur positioned for over the front wheel chain routing

The M-5 has two sets of chain idlers. There is the normal one set which routes the chain under the seat. There is also a set above the front wheel; these route the chain over the front wheel to permit somewhat normal turning (see top picture). If desired, the idlers over the front wheel do not have to be used; in this configuration the chain runs next to the front wheel (see lower picture). This provides better power transmission but more limited steering. Also, the front derailleur does not work as well in this configuration. A monoblade fork built from aero tubing permits the chain to run next to the front wheel without fork interference, and lowers wind resistance.

The U-2 is a special M-5 adaptation that is legal for USCF time trials. This version has a 24-inch rear wheel, and a shorter frame, making the total length of the bike less than 2 meters as required by USCF rules. U-2s won 5 USCF time trials before being banned. Read the full story here.

See the U-2 photo gallery here.