Question 350W vs 750W Motors — What Am I Missing?

Hey everyone,
I’m in the middle of planning a new motion build and I’m genuinely trying to reconcile something I keep running into.

Almost every build I see here (and on XSimulator in general) seems to be running much smaller DC motors in the 250–400W range. Some even less. Very few people seem to go beyond 400W.


However, when I dig into torque calculations, lever arm length, dynamic load under acceleration, and safety headroom, the math seems to suggest much higher power — sometimes closer to 600–750W per motor for a 2DOF seat mover.


So I’m trying to understand:

• How are people getting away with 350W motors?
• Are most builds relying on gearing advantage rather than raw power?
• Are people just running closer to stall torque than they realize?
• Is real-world motion load lower than theoretical load?
• Or is the 750W recommendation simply overkill?

I’m not trying to argue one side — I genuinely want to understand the engineering reality versus the common build practice.

If you’re running 350–400W motors:

• What motor model?
• What lever arm length?
• What driver?
• What PSU?
• Rider weight?
• Any overheating or long-term reliability issues?

If you’re running 600W+:

• Did you notice a major difference?
• Was it worth it?

I’d love to have an open discussion about what the actual best 24V DC motor setup is right now for a typical 2DOF seat mover — balancing torque, responsiveness, cost, and reliability.

Right now, 750W seems like overkill based on what I see people actually using — but maybe I’m missing something.

Would really appreciate the community’s real-world input.

You can run less power motors if you have a large reduction ratio

However, the speed of the sim will also be reduced

Aim for 800w or more if you are building a 6dof

Bigger motors, drivers and power supplies all cost more

Thanks for the info. Still kinda new to understanding all of this. I’m building a 3DOF f1 sim and want to have Heave as my 3rd DOF. chat GPT tells me I need minimum 750w 24v 90nm torque for each motor.. So now they have to be specially ordered from China and will take almost 2 months to get here.. and cost much more.. I guess maybe I’m just in sticker shock when it comes to building these things but everywhere I look people are using little wheelchair motors for like 100 bucks. Are those simulators just slower and less punchy??

Some of them do not do heave so less power is needed

A 2dof will require less power

You can fit heave assist with springs or gas strutts

But at the end of the day you can't beat having enough power

With 2D most of the weight is balanced on the Ujoint.

The OpenSFX system recommends 750w AC servos. The thing is the calculation for that configuration says it’s way overkill for the weight of a typical rig. It’s more about impulse torque requirements that are brief and can be huge. So it will work at 400w but may be sluggish for edge cases.

Are you planning on AC servos or DC servos? They are significantly different.