karlInSanDiego said:
Hi Kim, what did you decide on? My full suspension BBS02 750W ebike with 46T stock and 11T in the rear was great for commuting and my standard pedaling mildly hard speed was 30mph. I did burn a couple of controllers when I went too high with Amp settings, but the problem isn't having too high of gearing, but as you pointed out, starting out in middle gears to help allow legs/motor to get going without lugging motor. Just like a car/motorcycle, you must force yourself to downshift (but before stopping). I would have used 52T if it'd fit my bike. Then I would have been able to use my whole rear cog. I almost never use my lowest gears (24T & 28T). Now I'm going to try the BBS-02 750W with 52T on a Greenspeed GLR trike.
I ended up returning the lekkie bling ring 42t (+$100) and the lekkie buzz bars (+$100)
and bought the 44t, 48t, 52t chainrings from bafangusadirect.com (-$73 shipped for all 3)
and bought the 114mm and 140mm cranks from unicycle.com (-$48.40 shipped for both pairs)
After doing a quick test of the 44t, 46t, 48t, 52t stock bafang chainrings, I've settled on the 44t chainring for now.
May go back up to the 46t in the future because I did notice a dip in top speed, but I did also notice the corresponding increase in torque which is why I settled for now on the 44t.
average extended cruising speeds while jamming throttle and medium pedaling in 11t gear on:
44t ~30mph
46t ~35mph
48t/52t ~37mph
average burst top speeds while jamming throttle and hard pedaling in 11t gear on:
44t ~ 35mph
46t ~ 40mph
48t/52t ~ 42mph
I would definitely rule out the 52t on my bike setup. Did not notice any benefit over the 48t. Only thing it seemed to do was increase power draw, lower torque, motor ran much hotter, with no increase in speed over the 48t. The only reason I can think of to ever try out the 52t again would be if I switched the bbs02 over to a much lighter and nimble road bike.
I do not regret purchasing all 3 extra chainrings, thought it was a steal at $73 just for the fun I had experimenting.
Even the 52t I can imagine using in the future with a lighter bike so no regrets even with that one.
Also shipping for bafangusadirect is a flat $25 no matter if you buy 1 chainring or 3. the chainrings themselves are just $16 each.
The 114mm cranks were a joke lol. Completely unusable on my bike. But I love the 140mm cranks, felt very weird for the first 10 minutes, but I adjusted very quickly and noticed many benefits over the stock 170mm cranks. The main benefit I noticed was a smoother pedaling experience with less variance in the side to side rocking motion of my hips. Especially when pedaling hard out of the saddle. Also I liked the additional ground clearance and the fact that I could raise my seatpost a bit higher. I'm pretty sure these benefits I noticed disappear for anyone much taller than I am (5' 5" with shoes). I wish I had purchased 140mm and 150mm instead of the useless 114mm cranks lol.