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I wanted to ask what the gear ratio should be of my electric vehicle to allow it to have the fastest speed possible, while not blowing up my engine.
The vehicle I'm building has a Servovision 10 kW electric motor. I'll be running it at 48 volts. Further details of the motor are at servovision.
Clear from the table is the fact that the engine would deliver 3500 to 4000 RPM.
The diameter of my wheels is 24 cm (it's a kart). The drive shaft is 4 cm in diameter.
Is there any formula to calculate the optimal gear ratio ? And am I missing one or more variables to calculate this ? If so, what ?
Also, does resistance increase if the terrain is sloped (as I assume), and if so, is this calculated in in the formula ?
What I found so far is the following pages:
http://simplemotor.com/calculations/
http://www.bmikarts.com/Gear-Ratio-Speed-Calculator-MPH_ep_84-1.html
http://www.hotrod.com/articles/ctrp-0007-maximum-gear-ratio-equation/
http://www.instructables.com/id/Understanding-Motor-and-Gearbox-Design/
None of these however answers my question, although they do contain formula's. The instructables post also mentions there's something like a "Stall Torque" and a "Stall current", but I doubt any motor manufacturer will provide any such specifics, so I guess I best just calculate it out using other data as the basis.
The vehicle I'm building has a Servovision 10 kW electric motor. I'll be running it at 48 volts. Further details of the motor are at servovision.
Clear from the table is the fact that the engine would deliver 3500 to 4000 RPM.
The diameter of my wheels is 24 cm (it's a kart). The drive shaft is 4 cm in diameter.
Is there any formula to calculate the optimal gear ratio ? And am I missing one or more variables to calculate this ? If so, what ?
Also, does resistance increase if the terrain is sloped (as I assume), and if so, is this calculated in in the formula ?
What I found so far is the following pages:
http://simplemotor.com/calculations/
http://www.bmikarts.com/Gear-Ratio-Speed-Calculator-MPH_ep_84-1.html
http://www.hotrod.com/articles/ctrp-0007-maximum-gear-ratio-equation/
http://www.instructables.com/id/Understanding-Motor-and-Gearbox-Design/
None of these however answers my question, although they do contain formula's. The instructables post also mentions there's something like a "Stall Torque" and a "Stall current", but I doubt any motor manufacturer will provide any such specifics, so I guess I best just calculate it out using other data as the basis.