I've been playing around with an app call GPS Race Timer on and off. There's a section of road at the bottom of the hill with no traffic, at least for a few hundred feet for testing. I usually do a couple of runs when my battery is charged up, then go for a longer ride afterwards.
Besides weight, I'm starting to conclude that traction/tires is a significant limiting factor for acceleration for an ebike when using bicycle tires, even if the bike has power to accelerate quicker. After the tires hook up, power becomes the bigger factor, and where in the curve that power is located.
I'm using this thread to log results of doing small tweaks to see how they affect 0-30MPH times. I'd be interested in how other ebikes perform as well.
I setup the app initially testing 0-20MPH times. The data was fairly consistent, but I felt 0-30MPH would better represent the range I normally ride in. 0-20MPH times were around 2-2.2 seconds, heavily dependent on the launch. 0-30MPH times hover more around 4 seconds, and 200 feet, in my initial tests. I launch the bike the same way I would with a motorcycle, body weight forward, flat in almost a prone position. My head is over the front wheel. My best times happened when I can keep the rear wheel from losing traction, and the front tire is about 6" off the ground for the first 30 feet or so. I think if I could get my weight more forward without losing traction, then more of the power will be used to accelerate the bike forward, but that may be the limitation of bicycle tires. The weight savings would also be a factor.
Here's one of my runs from initial testing:
Bike weight: 82lb
Total weight: 261lb
Motor: Leaf 5T
Controller: 70A, 200A phase
Battery:
20S: 52V28Ah 14S8P 40A/60A peak + 6S lipos
Total voltage under test conditions: 82V
Tires: 24x2.8 @35psi
I plan on trying a couple of things next. The first will be to lower the tire pressure and more weight forward, which should help with traction. The second will be to remove my 52V pack and use all lipos. That may help with voltage sag that I might benefit from in the 20-30MPH range. I'll probably try a couple of 0-20MPH runs under these conditions to see where the benefit shows up most. If others want to participate, posting the summary data of the bike would be helpful.
Besides weight, I'm starting to conclude that traction/tires is a significant limiting factor for acceleration for an ebike when using bicycle tires, even if the bike has power to accelerate quicker. After the tires hook up, power becomes the bigger factor, and where in the curve that power is located.
I'm using this thread to log results of doing small tweaks to see how they affect 0-30MPH times. I'd be interested in how other ebikes perform as well.
I setup the app initially testing 0-20MPH times. The data was fairly consistent, but I felt 0-30MPH would better represent the range I normally ride in. 0-20MPH times were around 2-2.2 seconds, heavily dependent on the launch. 0-30MPH times hover more around 4 seconds, and 200 feet, in my initial tests. I launch the bike the same way I would with a motorcycle, body weight forward, flat in almost a prone position. My head is over the front wheel. My best times happened when I can keep the rear wheel from losing traction, and the front tire is about 6" off the ground for the first 30 feet or so. I think if I could get my weight more forward without losing traction, then more of the power will be used to accelerate the bike forward, but that may be the limitation of bicycle tires. The weight savings would also be a factor.
Here's one of my runs from initial testing:
Bike weight: 82lb
Total weight: 261lb
Motor: Leaf 5T
Controller: 70A, 200A phase
Battery:
20S: 52V28Ah 14S8P 40A/60A peak + 6S lipos
Total voltage under test conditions: 82V
Tires: 24x2.8 @35psi
I plan on trying a couple of things next. The first will be to lower the tire pressure and more weight forward, which should help with traction. The second will be to remove my 52V pack and use all lipos. That may help with voltage sag that I might benefit from in the 20-30MPH range. I'll probably try a couple of 0-20MPH runs under these conditions to see where the benefit shows up most. If others want to participate, posting the summary data of the bike would be helpful.