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Chain and Sprocket Calculator

Gearing Calculator - RPM to km/h - mph with Auto Shift Tracer   Enter Gear and Diff Ratios and drag RPM Slider

RPM gauge diagram Speedometer gauge diagram


Top Gear

Tire Diameter

Diff Ratio

Shift →
Slow Fast

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Gear ratio graph diagram
Shift →
Gear ratio RPM shift point graph diagram

Max RPM RPM Increments


See also: Printable Full Scale Degree Wheels Dial in your cam - and Printable Timing - Degree Tape

Enter Diff + Gear Ratios and Tire Diameter, then drag RPM slider to calculate speed from RPM.
Drag Max RPM slider to adjust the range of the RPM and km/h Gauges.

Enter Shift at RPM, select gear to shift to and hit Shift and Trace to run up through the gears recording shift point RPM and km/h.
Compare tires Check Compare and enter alternate Tire Diameter or Diff Ratio to compare. The speedometer will display a second needle for the comparison.

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DON'T BREATH THE DUST If you're cutting blocks, concrete, stone or ANYTHING and there's DUST - DON'T TAKE THE RISK
Don't cut it, or cut it wet so there's NO DUST - Silicosis Sucks
And if you're cutting wet, wear a mask - theres dust in the spray too!

How should we spell it?


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