TopCat wrote:I think you missed a bit in your reading of my post Amberwolf?
No, I got the part about it now smoking and heating up even on the "bench", but unless I totally misunderstood, you'd said that the problem started while riding on the bike--so I suspect it's now damaged from overheating (shorted windings, possibly, from insulation burned away while smoking during operation on the bike).
I don't know for certain what's wrong now or what caused the failure--it's just speculation based on my own often-failed experiments.
It is possible the gearing is all correct but that somethign is causing friction or dragging on the wheel or motor shaft or chain or something, but typically you'll feel that when just rolling the bike or doing off-ground tests spinning the setup by hand without batteries attached.
It is also possible (but unlikely) that it has "advanced timing" on the brushes, meaning the holder has been rotated to help improve operation at speed in one direction. This can cause high currents when operating in the other direction.
Typically when I got hot motors, I was pulling too much power from them, usually because my gearing was wrong, because I did not understand anything about motors really when I started my quest to motorize my bikes. It is why I wanted (and eventually got) a wattmeter, so I could monitor realtime power usage off the battery, as well as peak power and whatnot. It helps a lot when troubleshooting problems. Having a speedometer and odometer also helps, since I coudl then translate that into Wh/mile to figure out relative efficiency of setups.
Anyway, even just a voltmeter and ammeter kept attached to teh bike where you can see them when you ride will help; I did that, first, before the wattmeter, but I melted at least one ammeter because the current draw was higher than rated for and the shunt came unsoldered.
I've found in some experiments with gearing various motors that I would have been putting tens or even hundreds of times the power thru the motor than it was rated to take. Momentarily, that isnt' always an issue. But sustained, like when cruising, a motor is probably not going to be able to handle that kind of over-powering without some pretty radical cooling setup.
That's why it's really nice to have a wattmeter and keep track of power usages for various setups at various speeds and bike weight loads and terrain, because once you know a few of them, you can extrapolate what it will take for others.
I tested the Controller with my meter. I removed the motor connections and put the meter pins into the connections, I then turned the throttle and got a reading of 39.odd volts. I then reconnected the motor leads and turned the throttle, the motor span up for about 20 seconds then stopped?
If the controller was able to vary the voltage output and/or the speed of the motor then the controller was working and doing it's job. I'm pretty sure the problem is that your motor is being forced to do too much work at too slow a speed for it, so the current thru it is too high and it overheats.
Before you decide on a new motor, I think you're going to want to figure out the gearing of the bike vs the speed the motor is designed for. Meaning:
--determine what speed your wheel is going to turn at at the speed you want to cruise at.
--use that to determine what speed the sprocket on the wheel then spins at.
--use that and the ratio between that sprocket and the one you want on the motor to determine what speed the motor sprocket spins at.
--use that to determine what speed the motor will have to spin at to make that all happen.
Then pick a motor that has a rated loaded speed not very far above that, at most, at the voltage you want to run your system at. That motor will also have to be capable of continously running at the power level (watts) your setup takes to travel at your cruising speed. If you haven't measured that, you'll have to calculate it, which can involve some guesswork.
You can also just pick a motor that handles the power you need, at the voltage your system runs at, and then recalculate your gearing to match that motor's rated loaded speed at that voltage, so you end up with the right cruising speed.