neptronix wrote:GOT GOOD NEWS...
Battery: 20S/5AH charged to 81v.
Hill: 0.32 mile, 8.6% grade average, ~12% peak grade.
Conditions: 37 deg F. & no wind
Speed at the start of the hill ( ~3% grade ): 28mph.
Lowest speed at 12%: 25mph
Cruising speed: 30mph, at 120%, 33mph.
So yeah, i dropped an entire 3mph at the worst part of the hill. The motor was cold to the touch even after ripping around the street a few times in utter childlike glee at the 120% setting.
This motor is the real deal, boys.... I may actually have to dial down the amps because it has this nasty habit of wanting to throw you off. I doubt it is using the max 56 amps at all as the 5AH of year old turnigy 20C would have gotten hot at anything over ~33A for very long.
I do not have a cycle analyst to measure the amps/watts/etc just yet. I have one currently en-route from methods.
More later, including video once it stops snowing.
Brilliant, See I told you the Pie was a monster hill eater didn't I ?
So going from 26" to 20" really makes a major difference to the load on the motor, that's really cool!
It would be interesting to see how hot it would be on a longer climb, so it did 25 on 12% so it should do 20 on the 16% I went up, but the main thing is it shouldn't get too hot!
33 mph is not too shabby, but on 80 volts it's a lot of battery to carry around, but that was just with 5ah right? I was getting 33-35 mph max on 60 volts in a 26" wheel with 120% setting.
You would need about 100 volts to get to about 40 mph, but shit that would be scary with so much torque, on the + side though you could reduce the current even further if you wanted. 100 volts 10ah would be 1000 w/hrs for about 15 ish miles at 35-40 mph, not bad at about 55 ish whr/mi. That's the same wh/mi as a 50 volt 20ah pack for the same range, or more considering you would be going slower! I think you are into electric shock territory there ? maybe nothing serious just a little bite ?
It would have been better if GM had to make a faster wind for the smaller diameter wheels, I think the pie is too slow a wind, it has so much torque to start with it didn't need such a slow wind, but since they designed it to work with smaller batteries they wanted to maximise the amount of torque for the batteries and controllers they sell. They are not interested in making fast bicycle motors!
I would like to see how the HS3540 performs in a 20" wheel at the same 80 volts. According to the ebikes.ca simulator the HS3540 will go up a 12% grade at 24.9 mph, 50 amp controller, overheat after 5.8 mins. 115 lbs of torque. Strangely enough in a 16" wheel it says it will go up at 26 mph with 140 lbs of torque. That would nearly pull the bike apart!!!
So why does it say it will go up slightly faster in a 16", is it because of the extra torque ?
The new Volkswagen Golf 1.2tsi turbo petrol manual 122hp has 144 lb/ft and the HS3540 has 140 lbs in a 16" wheel, holy shit that would out accelerate it something crazy, to about 20 mph lol still, that's some power!
Dave I say to hell and go 100 volts, if you can afford to spend more on a new controller that is, I don't think the 4110's would take that?
2 x 20" wheels and you will be a lot lower, less wind resistance and it would be a lot steadier. Now if you only had a full suspension bike!
Back to pedal only power.