Free Tools
Free Dirt Bike Tools
Three free calculators for the garage, built on owner's manual data and cited on every page.
Premix Ratio Calculator
Work out 2-stroke oil for any amount of fuel in gallons or liters, with OEM ratios for KTM, Husqvarna, GASGAS, Yamaha and Beta.
Dirt Bike Sag Calculator
Turn three measurements into race sag and static sag, compared with the target in your owner's manual.
Dirt Bike Gearing Calculator
Free dirt bike gearing calculator: enter front and rear sprocket teeth to get final drive ratio, percent change and speed per gear from OEM gearbox ratios.
Dirt Bike Jetting Calculator
Free dirt bike jetting calculator: enter elevation, temperature and humidity to get air density, density altitude and whether to jet richer or leaner.
Engine Displacement And Compression Ratio Calculator
Free engine calculator: bore, stroke and cylinders to cc and cubic inches, plus chamber, gasket and deck volumes to compression ratio, with OEM presets.
2-Stroke Port Timing Calculator
Free 2-stroke port timing calculator: turn exhaust and transfer port height into opening angle, duration and blowdown, or degrees back into port height.
Service Due Calculator
Pick your model, enter engine hours, and see which owner's manual service jobs are overdue, due now or coming up.
Why These Tools
Most garage math comes down to three questions: how much oil goes in the fuel, whether the bike sits right for your weight, and what service is due at the current hours. Each tool answers one of them with numbers from owner's manuals, cited on the page, and runs in your browser with nothing to sign up for.
When you want the tracking done for you, MotoMind is our iPhone app for dirt bike maintenance by engine hours and date.
FAQ
Are the MotoMind tools free?
Yes. The premix, sag and service due calculators are free, run in your browser and do not need an account.
Where do the numbers come from?
From manufacturer owner's manuals, which are linked on each tool page. Where a value is our own convenience setting, such as a tolerance, the page says so.
Track Service Automatically
MotoMind tracks every bike by engine hours and date, so you always know what is due next.
