Converter operating-point comparison
Compare hypothetical converter reductions with a fixed chain drive and engine RPM. Change an input to explore the relationship.
Input parameters
Set your values below. The table updates automatically.
Comparison results
Illustrative operating ratios only. These are not specifications or a shift curve for any converter.
| Selected converter ratio | Overall reduction | Theoretical MPH |
|---|---|---|
| 2.70 | 13.50 | 10.31 |
| 2.50 | 12.50 | 11.14 |
| 2.00 | 10.00 | 13.92 |
| 1.50 | 7.50 | 18.56 |
| 1.20 | 6.00 | 23.20 |
| 1.00 | 5.00 | 27.85 |
| 0.90 | 4.50 | 30.94 |
How this table is calculated
overall reduction = chain reduction × selected converter ratioRows use the same assumptions while varying the value in the first column. Input-unit controls change the units used to enter values; column headers always state the output units.
How to read this comparison
Each row is a selected converter ratio multiplied by the fixed chain reduction. Engine RPM and tire diameter remain constant across rows, isolating the geometric effect of converter ratio.
A worked example with the initial inputs
With initial chain reduction 5:1, 3,600 rpm and a 13-inch tire, the selected 2.5:1 converter row gives 12.5:1 overall and about 11.14 MPH. A 1:1 converter row gives 5:1 overall and about 27.85 MPH.
The live table changes when you edit its controls.
Use the interactive calculator to explore more scenarios, units and relevant inputs.
Frequently asked questions
Are the listed ratios a real converter shift curve?
No. They are hypothetical comparison points. Use documented ratios for your equipment; engagement, load, slip and shifting behavior are outside the table.
Why do input controls and column headers show different units?
The unit toggle changes how you enter dimensional inputs. Each output column keeps its stated unit so you can compare values consistently. Read the column header before copying a result.
Understand the method in more detail
How to calculate go-kart gear ratiosDivide the axle sprocket teeth by the engine sprocket teeth. A 60-tooth rear and a 12-tooth front produce a 5:1 reduction: the engine turns five times for one axle revolution.Go-kart gearing: acceleration versus top speedMore reduction increases ideal wheel torque for a given engine torque, while lowering wheel speed at a given engine RPM. Neither relationship alone predicts lap time.Go-kart torque converter ratios explainedA belt converter varies its drive ratio with operating conditions. Use a selected instantaneous reduction in a calculation, then repeat for another point instead of treating it as one permanent ratio.Source and assumptions
Angular speed and tangential speed. Gear reductions follow tooth engagement and conservation of rotation count.
OpenStax — University Physics: rotation with constant angular accelerationRead the calculation methodology for model scope, unit conventions and review status.