Herramientas prácticas para trabajos de precisión
Convertidor de Velocidad a RPM
Convierta la velocidad en carretera a RPM del motor o del eje de transmisión, o RPM a velocidad, a partir del diámetro del neumático y una relación de marcha.
Selected gear x final drive, or driveshaft ratio for a 1:1 direct check
RPM = speed (mph) x gear ratio x 336.14 / tire diameter (in). The "336.14" constant is the exact form of the commonly-rounded 336.
Cómo funciona
What this converts: enter a tire diameter and an overall gear ratio (the selected gear's ratio multiplied by the final-drive ratio, or 1 for a direct driveshaft-to-wheel check), then either a road speed to find the resulting RPM, or an RPM to find the resulting road speed.
Formula. RPM = MPH × gear ratio × (336.14) ÷ tire diameter (inches). The constant comes from converting miles-per-hour into inches travelled per minute (63,360 ÷ 60) and dividing by π to turn that into wheel revolutions - it's the precise version of the 336 constant used in most driveline reference charts.
Example. A 26-inch tire with a 3.55 overall ratio at 60 mph turns about 2754 RPM.
Ejemplo con los datos actuales
El resultado anterior utiliza exactamente estos valores. Esta captura se incluye al imprimir para cotejar la salida con las medidas originales.
- Solve for
- RPM from speed
- Tire diameter
- 26 in
- Overall gear ratio
- 3.55
- Road speed
- 60 mph
- Engine/driveshaft RPM
- 2500 rpm
Resultado principal: RPM: 2754 rpm.
Antes de usar el resultado
- Measure from the datum or reference edge described by this tool, and do not mix inside, outside and centerline dimensions.
- Keep inputs in the displayed units and preserve more precision than the final cutting or purchasing tolerance requires.
- When the result is close to a limit, verify it with a test piece, field measurement, manufacturer drawing or qualified project professional.
Limitaciones
This is drivetrain gearing math only, not a tire-fitment check. It assumes no wheelspin, converter or clutch slip, and that the tire diameter entered is the actual rolling diameter rather than the nominal sidewall figure. For a full multi-gear plan across an entire transmission, use the Gear Ratio, Road Speed & RPM Planner instead.
Preguntas frecuentes
What gear ratio should I enter for a driveshaft RPM check?
Enter 1. That treats the ratio input as a pass-through, so the result is wheel/driveshaft RPM directly rather than engine RPM through a transmission gear.
Why does a bigger tire lower RPM at the same speed?
A larger tire covers more ground per revolution, so it needs fewer revolutions - and therefore lower RPM through a fixed gear ratio - to cover the same distance in the same time.
Should I use nominal or measured tire diameter?
Measured (loaded/rolling) diameter gives a more accurate result. Nominal sidewall diameter is close but real tires rarely match it exactly.
Herramientas relacionadas
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Compare dos tamaños de neumático lado a lado: diámetro, flanco, circunferencia y efecto en el velocímetro.
Calculadora de Offset
Compare una configuración actual y propuesta de rueda/neumático y vea exactamente cómo cambia la geometría.
Neumáticos Alternativos
Encuentre tamaños de neumático estándar, incluidos distintos diámetros de rueda, que mantengan el diámetro total dentro de una tolerancia elegida respecto al tamaño original.