Electric Paramotor Maintenance

We don't know yet. Csaba's machine is but a prototype and much will depend on the quality of the first production machine. Don't think in terms of your room fan, though, any more than you would compare paramotor reliability with your lawnmower. These machines are optimized (read that compromised) for weight. 20 hp dc electric motors have been available for years along with the battery power to propel them reliably for hours. And they can be run for days on end, even years. But that setup would weigh well over a hundred pounds. It's the necessity of making everything lightweight that bears most blame for any reliability issues along with the extremely limited market.

The most encouraging news comes from the model airplane crowd from which most efforts have sprung: their reliability is exceptionally high. Keep a motor's windings from burning up and it will run for many hundreds of hours. There is little to lube and nothing but bearings on the motor itself since they use brushless technology. 

It's a given that the batteries will wear out just like they do on cell phones and other rechargeable devices. But if you mind the recharge instructions, you can expect several hundred charge cycles from them. Periodic battery replacement will likely be the biggest cost item but won't be any more than the various maladies the suck green from piston-powered wallets—and it's far more predictable.