Beginner Easy Ebike Kit

[jack]

I want to put together a simple ebike. I'd buy prebuilt, but anything nice seems to be at least $4k, and not as good as a < $2k DIY

I'll use it for fun (small bit of offroading too), for going to the store, and going to friends' places. I've been riding motorcycles for about ten years if that makes a difference.

Stealth and speed are really important to me.

I'm about 165LB (75kg).

I'm in San Luis Obispo, California.

Here's what I'm looking for:
-30mph (40mph would be awesome)
-10 mile range (mostly flat, have a couple of very steep hills that I can just pedal up if it's a problem)
-sine wave controller for quietness
-locking/removable bottle-mount battery (is there some way to secure triangle bags so people can't as easily steal them?)
-ability to go down stairs (3-4) and hop curbs
-This is the bike I'm thinking of converting: http://www.bikesdirect.com/products/gravity/fsx_2.htm (and putting slicks on). Will a battery fit?

There are so many options. Most seem to be around 1k for kit+battery. The leaf motor seems like a good one, but I don't see many build posts about it other than from neptronix and a few in the megathread. I've also looked at the MagicPie 5, bbs02, and some of the cheaper ones like http://www.amazon.com/gp/product/B00Q8JT9H2 (how is this compared to the leaf?)

Here's the totals I've found (w/o bike, but including shipping to the US):
$1,040 MP5 (from lunacycles, 52V/9Ah battery is out of stock)
$1,072 Leaf (sinewave? 48V/11.6Ah)
$700 Amazon/ebay kit (48V/11.6Ah)
$1264 BBS02 (greenbikekit, 48V/11.6Ah)


What should I get, and where should I buy everything from? Have I missed any good choices? Am I missing any parts I'd need?

Cheers!

 

[Relampago]

I ordered the leaf motor but went with luna cycle for the battery. If I were to do it again, I'd go all luna cycle just because of their customer service. That and the built in bluetooth dashboard option. They have great prices and super fast delivery. The leaf motor is nice but I'd hate to have to ship it to china should something go wrong.

 

[dogman dan]

Well first of all, you won't be getting 40 mph from any 48v system I know of. But that's good, because that bike is not made for hard riding at 40 mph, at all.

It could be upgraded with a real rear shock, and new forks, but I have no idea if the frame is stiff enough for a real hard ride. The price range of bike you are looking at is made for two kinds of customers. One is a teen, that will ride it maybe 1000 miles, then dump it when he gets the car. The other is the fat old dude that won't even ride it 100 miles before it starts gathering dust in the garage.

Where you clearly seem to be headed in the end, I cannot stress enough, your first decision should be to get a much higher quality full suspension bike, likely used, since $2000 for a good new one is a lot of $$. What you get is a frame with good stiffness, and one that will not get less stiff as you ride it with the extra weight of the motor and battery aboard. The really cheap bikes soften up, and then start to ride like the frame is rubber. The tubes are cheap and thin.

I'm saying this because I get this feeling that you really do want to go 40 mph, and will want it soon. But if you really will be riding less than 30 mph, then even some very cheap bikes can be all you really need.

 

[wineboyrider]

Neptronix claims to get 40 mph on a 48v leaf motor, but I think it's a 50 amp controller and a fast wind. 8)

 

[Relampago]

Nep's build is what I modeled mine after, minus the limit pushing. I don't intend to go over 30mph, but in Nep's video he hits the 50's albeit for short runs and higher motor heat. His controller was the 12FET4110, but he recommended the 12FET3077 for lower demands. Plus, his motor is the 1500w leaf and he seems confident it can do mid 40's with a better controller like the 18FET4110. I wouldn't want to push a motor to those limits anyway since I'm not interested in hot rodding and finding ways to keep the hub cool to prevent heat damage, perfectly comfortable with the IDEA of speed and maybe not so much the execution of it.

 

[wesnewell]

Please fill in your profile location. Any cheap 48V 1000W DD kit on ebay will hit 30 mph all day long on a 48V battery pack. For 40+ mph you'll need a new controller and a 72V+ battery pack, and then you'll have to limit your time at higher speeds to not burn the motor up. A 48V kit rated for 40 mph will be a faster wind motor like Leafbike sells, but it's only practical for flat terrains like Florida. In hilly areas people have burnt them up fast. A typical ebay 48V 1000W kit like the yescomusa one is ~10Kv wind, meaning 10 rpm's per battery volt unloaded speed.

 

[wineboyrider]

Nep's build is what I modeled mine after, minus the limit pushing. I don't intend to go over 30mph, but in Nep's video he hits the 50's albeit for short runs and higher motor heat. His controller was the 12FET4110, but he recommended the 12FET3077 for lower demands. Plus, his motor is the 1500w leaf and he seems confident it can do mid 40's with a better controller like the 18FET4110. I wouldn't want to push a motor to those limits anyway since I'm not interested in hot rodding and finding ways to keep the hub cool to prevent heat damage, perfectly comfortable with the IDEA of speed and maybe not so much the execution of it.

Sounds to me you have done your homework! Anything over 30 mph is a little bit scary territory on a bicycle frame, but possible and safe if you have your braking situation also worked out.

 

[brumbrum]

40mph + pot hole = picking up teeth with your broken arms.

Have you tried riding an ebike at 30 or 40mph? Over 30 and things begin to blur. 30mph is do-able and reasonable, you will being getting air over small bumps on trails at 30.

Did someone mention fat old dudes? :x

 

[dogman dan]

Not surprised a faster at 48v motor wind exists, but it's not typical.

Best and cheapest approach still remains to build a fairly cheap 30 mph bike first, using a motor such as the yes kits. Nearly any bike can be safe enough at that speed. Then later, a good 72v controller and new batteries can get you into the 40mph club. Presumably by then you have found a great deal on a decent full suspension bike with a nice stiff frame.

At 40 mph, with no suspension or just junk suspension, it can get real interesting just hitting a man hole cover unexpectedly. Suddenly finding yourself with the rear wheel 16" in the air at 40 mph on a bike is really a thrill!