DRW Tools

DRW Tools brings together essential two-stroke engine tuning calculators in a single app, designed for customizers, tuners, and motocross, karting, and minibike enthusiasts.

Six calculators, all offline and without an account, are organized into four sections:

• Timing — Calculate timing (transfer, exhaust, intake) based on bore, stroke, and degrees of opening/closing

• Timing Advance — Convert between degrees of ignition advance and millimeters before top dead center

• Mixture — Quickly calculate oil/fuel ratios for any mixture ratio

• Head — Everything you need to know about the combustion chamber in a single section: Chamber Volume (net volume and compression ratio from dome, squish band, and flat/conical/bowed piston crown), Squish Area (percentage/millimeters of band, bidirectional), and RDC (compression ratio from a measured chamber volume, for example, with a syringe)

All calculations are performed on the device: no data is collected, saved online, or shared with third parties.