O.S. Engine OS-1A100 - Speed R2102 Compact 1/8 On-Road Race Engine  [OS-1A100]

Track Focused Power from O.S. Engine OS-1A100

For racers who value precision on asphalt, the O.S. Engine OS-1A100 - Speed R2102 delivers a well balanced package for 1/8 on-road competition. Its engineering emphasises consistent power delivery and reliable operation lap after lap.

Engine Internals and Performance Notes

The OS-1A100 carries a 3.49cc displacement with a 16.08mm bore and a 17.2mm stroke, giving it the physical characteristics suited to serious race builds. Its practical RPM window runs from 4,000 to 45,000 RPM, and measured output is 2.8ps at 33,000 RPM for strong top end and usable midrange.

Upgrades That Improve Durability

This version replaces the previous steel rear bearing with a ceramic rear ball bearing to lower friction and extend service life. The cooling head is set 3mm lower to reduce the centre of gravity, helping stability through fast corners.

Tuning Options for Different Tracks

To help match engine response to varying circuits, an extra inner head is supplied as standard so you can bias torque in the low to mid-range. That flexibility is useful when dialing in clutch and gearing for specific surfaces.

The O.S. Engine OS-1A100 is built for experienced 1/8 on-road drivers who need a durable, tunable engine that performs consistently across race weekends.