chas58 wrote:motomech wrote:

Take the original 328, which we haven't looked at closely. I have counted the gears for an overall ratio of 10.8 to 1 and that ratio corresponds very well with the **Ebike CA sim. which shows a no-load motor speed of 285 rpm @ 36 V**.

I'm confused, maybe you can help me understand. You are stating the simulator shows no-load 285rpm at 36v

The simulator below shows:

- No load speed of 385

- Load speed of 291 (36v17a)

What am I missing?

It's simple really.

I used a 15A controller, which is more representive of what was/is used with the majority on Cute builds.

Remember, a 328 in a big wheel is current limited, not rpm limited.

Note that the red plot (power) extends past the no-load point before it takes a dive.

It is this rather tippy balance @ the no-load point that makes running a small, high-speed, motor in a big wheel attractive(highest top speed for motor size, ability of rider to add significant speed, as little as 100 Watts will take the top speed from 22.5 mph to 25 mph!). But the other edge of the sword is reduced efficiency, controller trying to run max. and greater ease of the motor falling into the dreaded >50% of max rpm on hills).

I'm not that fit rider on a road bike, so my attempt to use mini's with a reduction ratio that gives the highest road speed took a different tack.

Smaller wheels weighted the compromise a bit.

Larger, less prone to get very hot controllers acted as a "stop-gap" fix, not really getting at the root of the problem.

And finally, 2WD, which, once all the details were worked out, worked pretty well. More or less like a 290 rpm BPM on 30 Amps, just not as powerful and more complicated

Still, getting a mini powered(even two of them)Ebike on 12S up to 28 mph was rather intoxicating.

But after a while, the speed thrill wears off and that extra 3 or 4 mph just doesn't seem worth the trouble.

Right now, the 2WD is being converted to 201's to cruise the sandy roads around the beach area I'm at.

But I think my ultimate Q100 powered 2WD is going to be a 260H in frt. and a (yet to be built)260 CST rear.

That is my motivation of looking at the possibilites of Q100 parts interchangeability