Looking At Possibilities - Help Needed

Good prices on that web site. Brands doesn't mean much in this kind of stuff (motor consists of some steel , aluminum , copper wires , bearings, hall sensors and leads - some motors have overheating protection) and they are , mostly , coming from China - cost is the only reason and quality isn't in question; don't mix it with inexpensive stuff from China . Brand might have something to do with customer support , which mostly refers to various components in the kit (controller , throttle and so on...) - other than motor - motors are rarely broken.
Ie. 9 Continent or Golden Motors are brands - but suspiciously similar to Crystalyte (China) - which is cheaper (doesn't include shipping) and very reliable and you can find motor characteristics and geometry on their web site , which isn't the case with "brand" ones. If you like "plug&play" go for a kit (don't have recommendation, the web site you posted seams OK - other members might help with it) and 36 V kit is OK for your requirements (you can over volt it any time). Overvolting often requires dedicated controller (usually the one that comes with kit can't be adjusted to work on higher voltages - but there are exceptions and you can buy controller separately with "stretched" voltage rating - ie 36 V - 72 V , 48 V - 96 V...). More Volts , higher the speed and less strain on battery pack.
Range of 20 miles is easily achievable with SLA pack , but dependable on terrain (hills , flat ground?) and conditions (winds, temperature) and your weight . On flat (maybe few mild hills with pedal assist) , with ~200 lb rider , 36 V 15 - 17 Ah battery pack would do the job (there is a bit of overkill , but better safe than sorry). If 20 miles is a round trip you can go with lighter battery , like 12 AH (if you can recharge on the other end).
500 W motor is under 1 HP - if you calculate it the way ICU's are (0.754 KW=1 HP). But there is a thing (luckily for you , police doesn't do too much math) with efficiency. ICU has around 20% efficiency and hub brushless motor (from your web site) has 80% efficiency. That means that hub motor is ~4 times more powerful than equivalent IC motor - which means 500 W hub motor has about 2.65 HP (other inefficiencies in system are neglected). Really , I've never heard that someone had problems with police on electric bike , even dough I know some people who made (and ride) bikes with more power than average motorcycle (ie Yamaha 250 ccm).
Hope this helps.

I personally don't care for hub motors but that's just me. For a discrete ride, go hub. Go at least 500 watts. That is the minimum I would buy. You can BE dui on a bike, but I'm not sure that not having a license would be enforceable. The federal government sees these low powered e bikes as bicycle not motor vehicles. In general a state can not pass a law that supersedes a federal one.

Nonetheless for your basic issue it's going to be batteries that make it obviously an ebike. Sla of any range are big and heavy. The jury is out on nimh as far as I'm concerned, but I'm still hopeful. For ability to hide them it's litho for sure.

Discreet and no more than 20 mph, a rear mounted 24volt 450 watt hub motor. 2 12volt 12ah sla batteries are easier to cover up than 3 or 4. You can make your own 24volt battery pack using a small packpack from Walmart or get a rear rack bag. I also suggest buying an aftermarket center mount "Y" type kickstand also. With just the weight of 2 batteries up high, it really makes the bike unstable on it's single leg kickstand.

Me, I'm partial to my Curry rigs. Discreet they're not. They stick out from the rear wheel like a sore thumb and give off pretty good whine from the gearing. People WILL turn their heads to see where the noise is coming from. The wife likes the hub. motors cause they're so quiet. But, you know us guys. Certain things are just meant to be noisy. Louder the better, like the sound of a fuel altered switching over to nitro from alcohol during a warmup.

If you're traveling 15-20miles each way every day your batteries are going to be depleted twice a day and will not last for long and can only be recharge a certain amount of times. You will either have to join the battery of the month club or stock up on batterys. I would go with a gas motor kit.

I used to have a 24v electric bike with 2 7ah batterys, I was only able to recharge the batterys 75 times and not the 300 times they stated. I traveled 2.5miles to work and 2.5miles back home.

I just saw this on here,copy and paste the http:// etc. below and see happyjack
#132 permalink
This thread is located at:
The nimh battery build... - Page 14 - Motorized Bicycle Engine Kit Forum

lots of sites of battery imfo today

Cabinfever1977 said:

I used to have a 24v electric bike with 2 7ah batterys, I was only able to recharge the batterys 75 times and not the 300 times they stated. I traveled 2.5miles to work and 2.5miles back home.

Click to expand...

I was just thinking you might have better luck with 10 or even 12ah batteries. 7ah sounds kinda small. I know the Izips and Ezips use 2 12volt 10ah batteries in their battery packs. My commute is just a tad shorter than your's, I don't use my bike everyday, but my used 12ah batteries are going on just about a year, now. They still charge to just over 13.2 volts. The only batteries I've had problems with are the ones that came with electric scooters where the owners didn't maintain the battery charges properly. They simply let them sit for several months before deciding to sell the scooters. These never charged up more than 12.7 volts. Not so good.

My electric bike was a mongoose electric bike from walmart.
I did use it everyday and recharged the batterys everyday.
After 75 recharges the batterys would not charge fully and i could not go more than 1mile. I scrapped the electric bike and bought a gas kit. I still like electric but don't have the money for a good electric kit or bike and not sure if i could afford to replace batterys that often. My gas kit i just put in 45 cents in my tank every few weeks and i have a $3 quart oil bottle that last for months.

I know that this isn't thread for it (I just had the urge to share this) , but you can't go much stealthier than this : Endless-sphere.com • View topic - BELIEVE IT OR NOT...20kW (26hp) in a 5305.. DONE =) (there is a picture at the end of page)

The sla thing I have used two sets of sla and they both still charge to over 13.5. I never ran them to less than 12.5v and I charged them after every ride. More range less weight and I wouldn't even consider another battery chemistry.