Battery Vehicle Society

Since the "to clutch or not" thread ended up as a highly technical debate between a couple of experts, I thought I'd restate my question here. For those who've not followed the "clutch or not" thread, my query was: what level of motor output/ vehicle all up weight ratio is needed...

Stimulating idea, Jeremy and to my mind just what BVS should be doing. Logic says to me that lots of motor ends instead of just 2 has to be heavier, but I'll take your word for it on the efficiency side. I like the idea of making the sandwich plates form a plenum for cooling air, as well as an indep...

Jeremy, getting back to the question of clutch or not: this million or so vehicles with no clutch or gearbox; what would be a typical motor kw output to vehicle all up weight, to permit one-speed transmission ? All along in my study of requirements for a sensible EV I keep running up against this qu...

Like you Richard I'd like to know what people who've retained the clutch do here. The absence of a response is interesting..... Extra mass of any sort is the enemy of the EV builder and I agree, you don't want the old flywheel in there. By the time it's adapted to the motor, machined down to a minim...

Have you looked at wheel alignment, Chris ? On my Fiat the book says up to 4mm toe-out at the front. Better handling for fwd, maybe, but not good for drag. Experiment towards zero. Don't forget the rear too. Old car = possible abuses. Otherwise congratulations for just getting on and building the th...

On the website you posted I see the motor is rated 24-72V, but you're using 96V. Is there any kind of rule of thumb for upping voltage like this on these industrial motors ?

Thanks,

Hi Malcolm, Going back to your response to my offering: not only does torque fall off to nothing at the no-load speed, horsepower does too, being a product of torque and revs. Since at top speed you need a lot of power, the gearing, or electricity utilisation at this point will need to be rather dif...

Bobc, Speaking of fuddled maths: 6 cubed is 6x6x6 when I went to school; this makes 216kw by your reasoning - clearly not correct. The source I quoted for the formula I mentioned also listed a number of real cars for which these sums had shown agreement. I am no mathematician and simply use stuff wh...

Malcolm, A couple of points about vehicle design: 1. weight has a direct affect on acceleration, but only minor on top speed; 2. top speed is the product of horsepower or kw versus frontal area and form drag - which means mostly aerodynamic resistance. Aerodynamic drag increases as the square of the...

Hi Dave, The serial no. is FM860615. It's 405mm long including fan (body 230mm) and 190mm diameter. Other data on the plate is as follows: S2 15 MIN; S3 20%; Mat. 03-00/51; IN 230; IS H IC _; IP 20 I've not included the stuff I recognise like rpm, kw and voltage and Ecc SER. IS H I figure is class H...