Electric Bikes - Choice of 24V vs. 36V for Front Hub Motor

I'm interested in buying one of these low-cost Chinese import hub motor kits and I have basically narrowed my choice to between a 24 volt 250 watt unit versus a 36 volt 350 watt unit. The 36 volt unit is only 25 dollars more so cost is not the issue - I'm more concerned about speed and range. I don't want it to be too fast when unassisted because I will use it only for recreational biking, but around 10 percent of my route has occasional hills, no more than 15 degrees slope and no more than 1/4 mile length at most. My main objective is ease in pedalling and longer range. I understand the 24 volt actually has a longer range because it has 2 each of the 17 AH batteries, while the 36 volt has 3 each of the 12 AH batteries. But they also say I won't notice the difference because the extra distance is only in the lower ranges - I don't really understand that. And the batteries weigh about the same in total. I myself weigh around 200 lbs. I'm leaning towards the 24 volt because it seems it will carry me further and will not push me to higher speeds than I can handle (I'm 60 years old and no longer a speed demon). I just want to bike in a relaxed, leisurely fashion, smell the roses, and enjoy the scenery, over a 20 mile round trip route each time, and I'll be pedalling most of the way on gently rolling terrain.

Thanks for any suggestions.

Franzen

Some maths:
24V X 17Ah = 408Wh
36V X 12Ah = 432Wh
Theorectically 432Wh should have a slighly long range at the same speed/load condition.
But these two Wh are so close that it is practically unable to notice any difference in range at the same speed/load condition.

350W motor would give a better torque/acceleration and higher top-speed.

However if you drive both 250W motor and 350W motor at their top-speeds, then the 250W unit will have a longer range because the power against speed is not linear.

In electric cars and rrucks higher voltage means lighter wiring. Not much of a concern on bikes. Just a thought.

I've been using a 250watt Chinese hub motor kit on my tricycles for well over a year and I've got nothing but praise for the setup. For a lot of the time I've been using the e.kit I was doing pamphlet deliveries to around 225 households in the rural town where I live and my round took in one of the steeper hills in town. I used the e.hub to provide assistance to my pedalling because pamphlets and flyers weigh heavy (5-8 per household X 225) and even with the extra weight of the two SLA batteries the e.hub made a big difference to the speed and ease with which I could complete my deliveries.
The controller that came with my kit can be set for 200watts as well as 250watts and most of the time I ride using the 200watt setting. I don't have either a speedo or odo on my tricycles so I can't give you any speed or range data, but the simple fact that this e.kit is doing what I want it to do with complete reliability has to be significant. :)

Hi,

I'm no expert, but I did buy a 36v crystalyte 2 weeks ago. Our situations sound very similar. I'm 57 years old and weigh 212 pounds. Like you, I will only use the bike just for pleasure riding.

My top speed is about 15 mph. Nowhere near the 19-20mph that an 150 pound rider might expect (according to the literature on my kit). My weight must make a significant difference. 15 mph is not really very fast. It's barely fast enough for me. I wouldn't want a top speed any slower. It looks like you are planning fairly long rides. As the batterries start to deplete a bit, the top speed of the bike slows down also. That's another consideration.

I haven't ridden a 24 volt, but I think you will be much happier with the 36 volt. Better safe than sorry