calab wrote: ↑
Feb 13 2022 12:57pm
Wouldnt that throttle be a problem without it being a Leaf 1500w?
Yes, but magnified by the motor. It was uncontrollable with the old motor too, but not at the higher speeds. Basically this is an issue from going high in voltage, since the throttle represents a broader voltage range, so twice as much as running 36V for instance. With my 1000W motor, it would wheelie uncontrollably from the dead start or maybe up to 10 mph, but no wheelies above that otherwise. It would wheelie at higher speeds if I flipped the 3 position switch to high, while on the throttle, but not just by twisting the throttle.
On another note, I finally got around to fine tuning my WGain and AGain settings and now the motor is performing silky smooth throughout the range. I was getting some pulsing that would get pretty intense at higher speeds while accelerating. I don't know why I didn't fix it earlier, but probably not a priority given that I don't ride that fast most of the time.
EDIT 1 02-16-22 I broke my cheapo gopro clone during my last offroad ride. The trail was too rough and the internal lens components seemed to fall apart, and you could see in recorded video, parts moving around the lens and blocking the frame.
I ended up getting a real gopro, a used Hero 7. I can't believe how the stabilization works on the camera. Really impressive. I've only taken a couple of test videos, but the image is super stable, even over big bumps. I tried to capture the midrange acceleration I'm getting with the Leaf motor, but it's hard to show without some reference points. Here, I'm going under an overpass, entering at around 13 mph or so, and roll on the throttle after the first no parking sign, accelerate up to 30 mph, then shut it down about 20 ft before coming out from the underpass. Anyway, I'm going to be playing with this new toy for a while. I only played with the other one a couple of times, but with the stabilization, I can actually shoot some decent videos with this one.
EDIT 2 02-16-22 Did another temperature test this evening. I rode over to a short paved path, with starting elevation of 141 ft, motor was at around 38C. The path usually doesn't have many people on it at that time, so I could get up to my 20-23 mph testing speed. I start out at around a 7% grade and steepens near the top to just short of 18%. I had to slow down and act like I was pedaling in the middle for a while due to a dog walker.
I rode slowly up and past the park at the top acting like I was pedaling. Temp was around 68C. Next section of roadway is mixed 10% to 17% grades. I kept it right around 22 mph. I pulled over at the top of that section with the motor right around 90C. I let it drop to about 78C before continuing on.
The last leg starts out level, goes to 10%, then 15% at the end; elevation 676 ft.; or 535 ft gain. You can get a good idea of how the tires sound, since the bike is otherwise silent. Not too annoying, but not silent. It was interesting that the motor got back up to 90C pretty fast climbing at 10%, but only hit 98C at the top. You can hear the hum of the motor regening going back down. It's putting out 488W-600W when the bike has some speed, but only 250W-350W as it slows.
I may alter this route to cut out the short flat section (I made a right to let the motor rest instead of going straight at the intersection). That will shorten the distance, and I wouldn't have to make that left by the curve where I almost got creamed by that pickup truck. It would pretty much eliminate any flat sections that would allow time for the motor to rest/cool. I may be able to make it the whole way without stopping, but keep the motor under 100C.
EDIT 02-17-22 I tried another route today, basically with the same start and end points, but street only, which made it easier to maintain speed. I also didn't try to maintain a single speed, but just rode normally, but with a minimum speed of 20 MPH. The route has several turns, but only two intersections to deal with, and there aren't a lot of cars.
550 FT elevation gain; 1.1 miles; mixed grades between 7% and 20%; beginning temp: 31C ; ending temp: 89C
Average Grade: 9.5%
Started out at 31C. I'm usually pedaling so it felt weird riding throttle only, but fun at the same time. I fake pedaled a couple of times around people. The steepest parts of this section are about 15%.
This section is the same as the other route, but instead of going right at the second stop sign, I continue straight up the hill. This section is a gradually increasing grade, just over 20% for a short part at the top. The motor temp looked OK, so I sped up to about 30 MPH when the coast was clear. Motor hit 89C, so 58C rise over the starting point temp.
3-position switch set to low, so limited to around 4.3k
Short climb; 23.9C starting temp, 53.7C ending temp; 0.21 mile @ 30MPH, 14%
I've been too lazy to pedal lately, so playing around riding throttle only. Yesterday out by the bay:
The bike is still pretty silent, but you can hear that faint buzz of the tires.
The bike path was clear, so I tested what speed I could get to before the next intersection; one medium block.
0 to 42 to 0, battery half charged (~76V):
I ended up RMA-ing 3 of the 4 new lipos I bought since they weren't staying balanced. So I'm not using the piggy back packs in parallel with my 52V battery for now. Running lipos in series requires all the cells to be matched, just like when building a battery pack, and I noticed that they go out of balance during bulk charging if they aren't. Hopefully the new lipos are better then the first set. I got used to not having voltage sag, and it shows up under hard acceleration, adding 3/4 second to my 0-30mph time without them.
I did another one block speed run, and this time without the piggy back packs, I was able to eek out 44mph (technically 43.9mph) in about the same distance (I shut it down early since there was a bicycle going the other direction near the end). The difference between the two runs is the first was with the batteries at 76V, but with very little sag, and charged to 81V, but with a decent amount of sag from the dead stop.
The replacement lipos arrive a week ago and I've charged them a few times and they are staying balanced, which is great and a lot less hassle.
I just realized that I'm coming up on 4000 miles on the original set of brake pads that came with my Avid BB7 brakes. Looking at the pads, it looks like there's still a bit to go. I'll probably switch to hydraulic before they wear out. I basically barely ever use my brakes, even riding on all the hills around my house. Using throttle only, with slide regen, I just put the throttle at the speed I want to go, whether faster or slower, and at most intersectionns or slow sections, slowing down to the 6 mph the regen goes down to is all that's needed. I only touch the brake lever if I want to come to dead stop.
I took this video after climbing up my typical route, 600 ft, then down. I'm already most of the way down here, but you can see I'm keeping the bike at around 20mph, when coasting it would be going over 30mph, just by feathering the throttle, I slow down 2 or 3 times to 6mph, before taking off again. I only tap the brake lever at the very end.