Advice on buying ebike kit

[Roca]

Hello everyone!

I would like your advice on purchasing a ebike kit. I am 5' 9", 160lbs with a budget of 1k. I am looking to go at least 40mph, my travel is only 3.5 miles from home to work. I would like to convert either a fat tire bike (Mongoose Dolomite, which is on sale right now for under $200 shipped) or a stretched cruiser bike (craigslist or Micargi mustang GT). I have been looking at kits on eBay and it seems like the most ideal kit is the 1000w rear 48v but I don't think that could go up to 40mph. I also understand that in order to do the fat tire conversion that I would have to get my wheels re-laced or purchase a fat tire motor kit. I am also looking into an in-frame battery and controller set up. Thanks so much in advance! All suggestions are greatly appreciated!

 

[dogman dan]

Fat bikes are not for 40 mph. For starters, put a rear motor on a dolomite, and NO BRAKES! Nor will you have an easy time modifying a cheaper kit motor to 40 mph, on a budget that small.

A beach cruiser can be used, but bear in mind, a bad manhole cover on a no suspension bike at 40 mph can be quite an experience. Ever had a bike on just the front wheel at 40 mph? When I have done it, I was real glad I was wearing a lot of motorcycle armor.

Here's my advice, get a nice strong steel frame beach cruiser with 7 rear gears, and v brakes on both wheels. This will not cost a lot, and leave you $800 or so for a 48v 1000w kit. With a good strong lithium battery, these 1000w kits on ebay can do 30 mph. Believe me, 30 mph on a no suspension bike is plenty. You won't mind it that much that you don't have 40 mph.

Then, later on if you wish, you can modify the kit to run 72v, and reach 40 mph. But on a bike with good full suspension, that is capable of handling a bump in the road at 40 mph.

30 mph today, on your budget. Later on after trying 30 mph, you can decide if spending $500-1000 on a badass bike for 40 mph is worth it.

 

[mlt34]

I totally agree with dogman. 40 mph isn't for beginners. Hell, it isn't even for most people, as few on this forum have actually made it into the 40 mph club.

You can build a nice ebike for $600-800. The ebay 48V 100W kits are a good way to go for your first motor/controller and all the accessories. For a battery, you'll want lithium and I recommend a battery from BMSbattery.com or from sun-thing28 on ebay. 48V10AH should be plenty for you with a short commute like that, but if you want to spend just a little bit more, a 48V15AH battery will mean charging less and better battery health, not to mention longer fun rides when you aren't using it for commuting.

I have this battery on my daily driver, which has been going strong for two years now and still at about 90% capacity: https://bmsbattery.com/ebike-battery/166-48v10ah-li-ion-shrink-tube-ebike-battery-pack-ecitypower-battery.html

You can keep it in an ibera triangle bag, which will be a little bit of a tight fit: http://www.amazon.com/Ibera-Bicycle-Triangle-Frame-Bag/dp/B00H1KUCQY
(get the large size)

or there is the em3ev bag which you have to wait for china shipping: http://em3ev.com/store/index.php?route=product/product&product_id=125

or the new electric rider triangle bag which I just got one of and really like: http://www.electricrider.com/triangle-battery-bag-for-ebikes-p/bag-triangle.htm
it isn't much more expensive, especially after shipping from china on the other option.

Lots of good, inexpensive options out there.

 

[NeilP]

I'd have to disagree about 40mph not being for beginners ...that is if you have any form of mechanical ability.
As a total newbie I built mine up to plus 40..in fact it was accelerating at 55 mph. 100volt on a Xlyte 5304

so turned it down to 84 volt, 20 series.

Something like a Phoenix kit

http://www.electricrider.com/Phoenix-Electric-Bike-Conversion-Kit-p/x2-km.htm
http://www.electric-bikes.com/betterbikes/crystalyte.html

http://www.crystalyte.us/

http://endless-sphere.com/forums/viewtopic.php?f=3&t=66459


for your range, 10-12 Ah will be enough at 20 series, I have a 20 series 20 Amp pack and it can do 16-18 miles..though not at a constant 40.

If you don't have many hills, the then Cruiser kit is faster, for the same voltage compared to the Brute kit, so you could save money by going for the Cruiser motor and a lower voltage pack

 

[mlt34]

The phoenix kits are great. One of my first ebikes was an only Phoenix I kit. Amazing parts and great support from them.

I didn't mean that 40 mph is above the skill level of a beginner. Rather that it isn't advisable (in my opinion) for most beginners to start with that much power. Most ebike riders weren't motorcycle riders previously, and going those speeds on a bicycle which wasn't meant to go that fast can often lead to disaster. Starting with 30 mph is plenty fast and it gives new ebikers time to learn about their ebike, how the components handle different conditions and power levels, and how to ride at those speeds on a very specific type of two wheeled vehicle. There's always time to upgrade and go faster.

 

[wesnewell]

http://endless-sphere.com/forums/viewtopic.php?f=3&t=66302
if you're only going 3.5 miles, you can get a 1000W motor to 40 mph without burning it up, but not on 48V unless you get a high kv motor and it will have very little torque. If you can get by with 30 mph, it's a lot easier on 48V. And for only a 3.5 mile trip, there won't be much time difference at 30 vs. 40 mph.

 

[NeilP]

The phoenix kits are great. One of my first ebikes was an only Phoenix I kit. Amazing parts and great support from them..

I agree 100%, my mate bought one , abused the hell out if it, even to the point of settign fire to a LiFePO4 headway pack and destroying two controllers and chargers. including riding his 240lbs around with one, then two then three spokes brokes...and on mnay occassions too. he never learned, i eventually got th emotor fro free. My new GT LTS build. I got to knwo the blokes at electric rider (via e-mail ) veryu well while he had the phoenix Brute kit.

I'd go with a differetn controller though and jsut buy the motor from them. that way you are not saddled with the usleess ( in my opinion) Crystalyte APM, and its non programable controller. Get another cotnrolller..A lyen or E-crazy man, or one of the many newer nmore expensive ones if you have the mone, (adapto/ sevecon/kelly)

I didn't mean that 40 mph is above the skill level of a beginner. Rather that it isn't advisable (in my opinion) for most beginners to start with that much power.

possible, but i did with no issues, and so have many others. I was a motorcycle rider previously , and still am, harley Davidson now, but many iothers since I was 8 years old.

There's always time to upgrade and go faster.

but if you are on a budget, that often means disposign of the batteries you bought for the low voltage build and byuying a complete new set. as it is never a great idea jsut to add new packs in series to a block of old packs. So it does mena buyign two sets of batteries. As the battery pack is probably ...hell I don't know..60-70% if nto more of the cost...i'd go with the pack you need to start with. even if you then limit the speed artificailly in the controoller . Software like XPD can do that.

It all depends on the buidlers ability.

I was advised against big speed and power when I started, and I ignored that advice...I am very gald I did, otherwise I'd have been dissapointed with the final build and then woudl have had to spend more updgrading it afterwards.

 

[The fingers]

You can keep it in an ibera triangle bag, which will be a little bit of a tight fit: http://www.amazon.com/Ibera-Bicycle-Triangle-Frame-Bag/dp/B00H1KUCQY
(get the large size)

Thanks for the links mlt34. I am tempted to try this one upside down on my step through Fiore(flower) frame, which has the bottle mount between the curved frame rails for some stupid reason making it completely useless for battery mounting. :x

 

[Roca]

Thank you guys so much for the information! It is still a very hard decision for me because I can only do this once and not looking to spend more on future upgrades or what not. I'm looking for the best bang for my buck and I figured that 1k should suffice for the speed and distance I'm looking to get ($200 on bike + $200 on 1kw 48v kit + $600 on battery).

I appreciate the concerns for safety but I have been riding a lot of things with wheels since I was a kid from bmx, dirtbikes, skateboards, rollerblades, scooters, you name it! so I have a pretty good understanding of speed, control and balance.

I also currently am a rider and sold my toys recently which I have converted from basic cruisers to bobbers so I have a little electrical and mechanical experience. Here is a few pics:

Honda Rebel 450



Honda Rebel 250



Back to the topic, I considered modding a fat bike because of it's all terrain tires which would be nice to go offroad or on a trail sometimes and I would have the best of both worlds (commuter + offroad). With a nice springer seat and reduced psi, I think that the fat bike should have decent suspension (?). I also considered the stretch cruiser because of it's styling and lines, old school, and plenty of room for placing the components within the frame.

I've done research with the motors, batteries and all other accesories. Heard some good stories and some horror stories.

I do have a Magna Excitor with 26" wheels which I could use if I have to cut a part of my wants in order to obtain 40mph with decent mileage... I could just swap out the kit later on when I have enough for the look that I want.

So, for 1k, what is the best bang for my buck?

 

[dogman dan]

All I really meant about 40 mph, was on a really tight budget, it can get scary to go that fast on a bike with no suspension at all. At 40 mph, you can end up with either wheel way off the ground from a bump you never saw coming.

If he'd started out, "I have a reasonably good full suspension bike, and want to go 40 mph on a budget of $1500, not including the bike" Then my response would have been, "check out the muxus 3000w" yadda yadda.

Guy wants to go 40 mph, on a cheap ass fat tire bike with no brakes at all, well, hope he grew up on motorcycles. If he did, put a muxus on that fat bike, and regen brakes. He knows how to crash well. And how to handle a wheelie or stoppie.

When you tell a guy "go for it, 40 mph" it's good if you know he has riding skills or not. Well now I know! 8)


Average guy hops on the cheap bike he's planned, will be sitting on his ass as the bike flies away from him. He'll be going, "where did my other shoe go?"

I'm not telling Roca "don't do it". Just telling him his budget can easily handle 30 mph. 40 mph, he needs a bit more budget for the bike, IMO, like good shocks. And as always, the battery for 40 mph costs more than 30 mph.

No reason he can't build a 40 mph bike, but actually ride it 30 mph on any street he's not real familiar with. So a manhole cover doesn't thrill him more than planned. But again, I just don't see him doing it nice on only $1000 including the bike.

I'd say look into a more powerful motor kit, like the muxus 3000w motor and a 72v battery. I just rode some very nice bikes with that motor, using only 48v. No 40 mph, but a very fast off the line, very fun ride. On 72v, your bike will rock with that motor. A solid beach cruiser with v brakes can do it, but get steel frame so you can weld on some disc mounts later. You'll want them.

For your distance, 72v of RC hobby batteries will be plenty, even to make that run at 40 mph.

$1500 is a plausible budget, but truth be told, most of us end up more like $2000 or more.

 

[arkmundi]

So, for 1k, what is the best bang for my buck?

The simple question. Check out my Top 10 eBike Conversion Kits & Where to Buy thread for an answer to that. Nothing beats doing your own research & price/performance comparison, with a few pointers here on the forum. Look at the affordability options, including the Leaf DD and YescomUSA options, both of which will get you in the $200 range for the kit. You're right in wanting to spend most of your budget on battery. The way to do that is make it yourself from the cells.

 

[Roca]

Thank you so much for the information!

I decided to buy a used kit to "get my feet wet". 1000w with 48v batt. Everything looked fine until I noticed this on the wheel. Can someone please tell me what happened here and if it's still safe to proceed and install the kit?

 

[wesnewell]

If the axle spun out, it may have twisted wires inside and shorted them out, but it's hard to tell from a photo.

 

[Roca]

I hope this angle helps. I believe this is the reason why one would need a torque arm?





I noticed scratches on the thumb throttle as if the previous owner crashed or something....

 

[Roca]

Just hooked up battery to controller. Plugged thumb throttle to controller and battery gauge lit up. I really hope that the motor still works when I install it tomorrow morning...

 

[arkmundi]

Torque arm is a good idea. Wires can be replaced, all the way to motor attachment points, if need be. If your motor/controller/controls don't work, its a methodical process of test & elimination, but hang in there - the problem can usually be found and fixed. I like the idea of reuse & repair when possible. Best of luck.

 

[Drunkskunk]

The reason 40mph isn't recommended has nothing to do with your riding skill. It has everything to do with the average bike simply not being built to strong enough. There is a reason even mopeds designed to go 30mph use much heavier parts than bicycles. Every time you increase the speed by double, you increase the forces by 4 times. A cruiser bike from walmart is designed for around 15mph. at 30mph, it's taking every bump in the road 4 times harder. it's frame and wheels are getting the beating of their life. For many bikes, they are still in the range of probably surviving for a while, but not if abused. At 40mph, it gets even worse, and with it's leading edge walmart quality, you can use your imagination as to what will happen.

As for the Dolomite, it's a fatbike. Fatbike tires don't stand up to speeds above 30mph very well. I've got a lot of experience with this. at 35mph, I've had tires blister after just 2 miles. They aren't DOT approved, thick walled, puncture resistant motorcycle tires. they're balloons with tread. I've had to move up to some expensive tires and even then, I've run through them in 300 miles or so, at a cost of around 300 a set. Yes, that's a dollar per mile in just tire cost. I keep my speed down now, most of the time.

That motor does look like it's been spun. That might be a problem, but it might be fine. In most cases, it can be repaired if it did spin and twist out the wires. the only real concern I'd have is if the controller was damaged from the hall sensors being shorted with the main power.

 

[wesnewell]

My experiences are quite different. I'm 270lbs and and have had one of my bikes to over 60mph without a problem other than flying through the air a short distance when hitting a bump at that speed. That bike had CST Cyclops tires on it well over a year and 5000+ miles on them. The stock tires on the Dolomite are really big and heavy duty and really heavy for bike tires at about 5 lbs each. Mine look new after about 100 miles on them with speeds to close to 40 mph. A tire under inflated will heat up many times faster than one with the proper pressure in it because it will be so much more flexible. Keep the tires inflated to the proper pressure and you won't have a problem with them. For higher speeds, I wouldn't go below 25psi on the rear and 20psi on the front where the load is less. I agree that a motorcycle tire and rim would be stronger though.

 

[Roca]

Good evening all,

I just wanted to give an update on my project. I found out that the whole kit is still functional but the battery proved to be a lil bit too heavy for the bike that it toppled over when I rested the bike on its kickstand. Here is a video before the incident.




Shortly after that, I invested on a new 1000w homcom rear hub which is similar to the kit I was tinkering with. I also bought a v power 48v 20ah lifepo4 this time around which actually might be overkill for the 7mile daily work commute. I haven't decided on a bike to install the kit into but I'm thinking of selling the kit with battery to upgrade to a fat tire kit and smaller battery... or even a bafang bbs02...

 

[rider95]

Fat bikes are for slow speed and mostly off road I wonder if you have any Ideal what 40mph on a bike feels like ??

 

[dnmun]

without full suspension.

 

[The fingers]

Good evening all,
I just wanted to give an update on my project. I found out that the whole kit is still functional but the battery proved to be a lil bit too heavy for the bike that it toppled over when I rested the bike on its kickstand....

Even with a double leg vertical axis centerstand I have to be careful, especially to keep idots away from the bike while charging at work. One person decided to move it while plugged in and ripped the cord out of the wall receptacle. Good thing I checked it on my break to resume charging or it would have been a tough pedal of pain and an ordeal to make it home. :x

 

[999zip999]

Let us know how the v power battery works. I have heard mixed results.

 

[Roca]

Fat bikes are for slow speed and mostly off road I wonder if you have any Ideal what 40mph on a bike feels like ??

without full suspension.

I figured I would get more tire to ground coverage with the fat tire giving me better traction and control is why I would consider it. I have not experienced 40mph on a bike and if you noticed at the beginning of my thread, that is actually what I'm trying to accomplish. I can't pedal that fast and I have bombed downhills before but I'm sure it's not the same feeling. I did go 80mph+ on a hardtail motorcycle and I would consider that "without full suspension".

Listen guys, I am not a speed junkie and not looking to build an ebike for the thrill of the speed. I would just like to have the option to go fast in case that I need to get out of a scenario or emergency purposes. Of course I would go full throttle on a flat, empty road that I am familiar with but I do not intend to hop on the bike expecting to go 40mph the whole way.

 

[Roca]

Good evening all,
I just wanted to give an update on my project. I found out that the whole kit is still functional but the battery proved to be a lil bit too heavy for the bike that it toppled over when I rested the bike on its kickstand....

Even with a double leg vertical axis centerstand I have to be careful, especially to keep idots away from the bike while charging at work. One person decided to move it while plugged in and ripped the cord out of the wall receptacle. Good thing I checked it on my break to resume charging or it would have been a tough pedal of pain and an ordeal to make it home. :x

yikes! i'm glad nothing got damaged...