I'm new here, and I'm trying to decide on my first bike.

Joined
Feb 15, 2017
Messages
26
Location
Hood River, OR
Hey everyone,
My name is Logan and I'm a homeschooled 15 year old. I work part-time at a market and constantly am trying new things. I love things with wheels and motors (motorcycles, go karts, and so forth) and it's my time to move to electric.

It's time for me to build my first ebike. The more power the better, but I probably don't want to put over 1K in a first build.
I've been wanting to go with a 9C 48v 1000w motor but I know I'll get tired of it. This bike will be for practical trips (getting to work, 12mile roundabout) and also for fun.
I make about $200 a week. I'm considering selling my project dirt bike, but I should really work on it more first to get the best price. That would get me about 1K.

I've been researching batteries and hub motors for a long time. I only want to go with a hub motor, and I'm leaning towards 72v (I'm quite aware of the dangers of high voltages)
I recently ordered 8 of these packs:http://www.ebay.com/itm/NEW-SAMSUNG...d=100167&rk=1&rkt=15&mehot=pp&sd=172630688902
as I found them to be a great deal. I think even with multiple bmss I can link them together to form a 72v ~20ah pack. If not, I'll just link them into 36v 10ah packs and resell them.

So, any suggestions? I could buy a kit meant for 3-5kw at 72v, but that's most of my budget. I also thought of just overvolting (using a new controller) the 9c motor to 72v and running it at 20-40a. I have a kona dawg deluxe full-suspension downhill mountain bike with 200mm disc rotors, that I can use.

Any info, links, experiences, etc will be appreciated. You'll be seeing a lot of me here.
 
See need advice in sig
 
Does your $1k budget include the price of the donor bike? There's a bike being sold by a very reputable member of our site for $800 that has everything you need but the battery (and you seem to have most of it sorted there). It's a perfect match for your budget and it's also located in the PNW.

It has a motor rated at 1000W, but you can easily put 3kW or more with some mods (since you stated you will be around and likely grow tired of something too tame). It's very similar to a 9C, but much newer design including thin laminations for efficiency (less eddy [iron] losses)

Here's a link to it:

https://www.facebook.com/groups/Endless.Sphere.Sales/permalink/1114820575289577/?sale_post_id=1114820575289577

It's a closed group, but just request the add and I will approve it ASAP.
 
At what age can you get a street legal motorcycle in your state? Or does that even matter?

It was 16 in my state, but back then I did not hesitate to ride a motorcycle to work at 14. I had to get to work somehow, and it was 20 miles away. Maybe that can't fly for you. I took a mostly dirt route, so much of it was legal.

My best advice, which I certainly would not take at 15, is go with a modest but still very fun ride. A 9 c type motor with 48v 22 amps can still be very fun!. It will hit near 30 mph, which is about the max its really safe to ride streets anyway, on bike frames, tires, brakes, etc. (Dirt is another story)

DONT sell off your dirt bike unless you get a great price for it. You will want it later I'm sure.

The faster 72v battery and bigger motor will just cost you too much right now. Go with a nice cheap 9c type motor, and modest controller at first. As you can afford it, get a stronger battery, and go to 48v 40 amps, with a bigger controller.

Start with the appetizer, and as your budget allows, dig into the main course meal of a 40 mph e bike. BEAR THIS IN MIND. There is no legal difference between you riding a motorcycle on the street before you have a licence for it, and riding a homemade motorcycle with pedals on it.

But you can pedal like a clown when you see a cop, and maybe, just maybe pass a cop without a bust, on a 40 mph e bike. This won't work though if you are actually doing 40. He aint going to buy it you pedal 40 mph.
 
I overvolted a 9c to 60 volts and 55 amps it was crazy.. Go with 48-52 volts and keep the amps to 30 and a 9c type motor should live forever. Just don't lug it up big hills.
 
Thanks guys
That experi-MENTAL DD hub bike is interesting. I may contact him.
I do have a bike though, a kona, already.

Did anyone have any thoughts on those battery packs? Mine arrive today. I'll post some pictures and findings.

Yeah, it's 16 to ride a motorcycle and $350 for the endorsement in oregon. I sometimes do illegal activity (go karts and dirt bikes on the road) but riding a motorcycle to work is probably a bad idea. An ebike, even high powered, is acceptable here.
 
ultralight001 said:
Did anyone have any thoughts on those battery packs? Mine arrive today. I'll post some pictures and findings.


We get what we pay for, and $35 shipped for 10S-2P says it's probably trouble. These are probably surplus hover board packs, scrapped for some reason?

OK, I did buy one . Shipped safely in a sturdy box with correct/legal labels. Contrary to the ebay ad, the battery was shrink wrapped which was OK by me, because I would have wanted to do that anyway. I'll peek under the wrap to see what labels are on the cells.

I cycled it three times on my ebikes, and got 144 watt-hours each time. I think they're good for around 2-3A peak per cell. Maybe more. One will run my low power ebike though. Realizing its lack of history, I would not endorse it to anyone else.

I store and charge mine in a steel ammo can, and will be putting a temperature switch in my battery bag. I should have one there anyway.
 
At your age? Try a really good bike, with pedals. A light, efficient bike. For the next ten years, you'll never have a better motor for your bicycle than the one you were equipped with, and the more you use it now, the better it will work when you're older.

Also, for the next decade you're probably going to crash more than you will in the rest of your life combined. Better if you're not motorized for that.

If you want to fool around with motorcycles, wait until your thirties, when your craving for thrills is diminished and your need for stimulating diversion is increased. Motor vehicles are fundamentally unwholesome, and now is the time for you to set the tone for your whole life. Use your body while it's healthy and resilient. Learn about maximizing efficiency (a smart man's game) instead of using more power to compensate for shortcomings (a stupid man's game).
 
Chalo said:
At your age? Try a really good bike, with pedals. A light, efficient bike. For the next ten years, you'll never have a better motor for your bicycle than the one you were equipped with, and the more you use it now, the better it will work when you're older.

Also, for the next decade you're probably going to crash more than you will in the rest of your life combined. Better if you're not motorized for that.

If you want to fool around with motorcycles, wait until your thirties, when your craving for thrills is diminished and your need for stimulating diversion is increased. Motor vehicles are fundamentally unwholesome, and now is the time for you to set the tone for your whole life. Use your body while it's healthy and resilient. Learn about maximizing efficiency (a smart man's game) instead of using more power to compensate for shortcomings (a stupid man's game).

I agree with this mentality except for two things. Keeping my appearance good is one thing, it's not nice to come into work sweaty. I live in a very hilly area.
I'll probably play with motorcycles till I get married in my twenties and won't have time. I do love cycling, I've ridden some great street bikes 20+ miles on flat roads and felt great. But with ebikes, you can use it like a motorcycle, or use pedal assist and get exercise while covering a lot more distance.
 
Okay. Right now I'm thinking, go with a 9C motor kit, and buy a 48v battery. Or, I can use four of the packs I bought (36v 5ah) in series and parallel, and make a 72v 10ah pack (total battery
cost $130). Then buy a 72v 1000-1500w generic controller off ebay ($40) and somehow wire it to the kit components. That would be less than the cost of a chinese 48v pack, with samsung cells, and more power.
 
Sounds like a decent plan, You can still build your body up pedaling it hard as you like, or riding it in dirt hard, which is a work out even without pedaling it.

You don't need more than 2000w or so, which the 500w dd motors can do all day. go for 48v-52v, and 40 amps controller. Or less controller for now, if you get the cheaper kit for a starter setup. You will find 1000w is still pretty fun.

Bear in mind,, more controller, will either cost you a ton for a suitable battery, ( like 30 ah) or it will quickly sink your battery investment when it kills your battery. What you have now will be a pretty hard run just for a 20 amps controller.

Battery is what is going to eat you alive with e bikes, which is why I was suggesting a nice cheap 250 motorcycle next year. Getting that will be hard, if you use up 3 batteries this year. ( a thou or more).

Just don't get a suicidecycle at first, a crotch rocket that goes 100 mph. A 125 even, is a good starter bike. After you learn to lay that one down safely, move up, not before.
 
I don't want you guys reading about this happening to me and those ebay overboard batteries.

https://www.thesun.co.uk/news/3777723/cyclist-runs-for-his-life-after-electric-bike-explodes-in-a-fireball-under-his-bum/
 
Just another reason I will never use 18650, or any canned batteries.
 
Check Craigslist. Sometimes you can get a great deal on a used ebike that needs a little work. I scored a used A2B metro for $200 that was still working fine.
 
That is an incredibly low price. when I was looking at them used a couple of years ago, even when looking at Craigslist a few months ago to see what was being sold as far as e-bikes was concerned , I saw $ 900-$ 1500 asking prices for the A2B Metro.

About once every few months some great deal for the buyer does come up on bikes on Cl. I have noticed.

Ultralight 001, If / When you find a used e-bike, let us know here on E.S. what it is and its condition ... Before , you buy. There are many of the Old designs that are not even worth the time / effort / money , spent to fix up.



fechter said:
Check Craigslist. Sometimes you can get a great deal on a used ebike that needs a little work. I scored a used A2B metro for $200 that was still working fine.
 
Best thing you can do is read the ebike videos and photos section to read about other people's builds. It's a good way to learn what people have done, what problems they had, what things cost, etc.

Also, if batteries are too cheap to be true, they probably are. Plenty of scams out there.. best to stick with a reputable vendor.

Welcome to the forum, by the way.
 
Thanks for all of the helpful advice everyone, My dad lets me ride dirt bikes but as long as I live with my parents a motorcycle probably wont be allowed for "safety concerns." I'll build a bike, and then I'll post what I end up doing.
 
Stick to the topic, not the people.
 
Okay, I got my 8 packs today. 4 lg and four samsung, 5ah 36v each. Total spent, $260.

I've examined all of these packs and they are very well made with true quality cells. These are genuine samsung and LG cells and all of the packs are at about 39.1-41.0 volts. I'm charging one pack now.

At this point, I want to link them all in parallel and make a monster 40ah 36v pack (which would still be pretty small in size). The 36v "500w" kits on ebay have 25A controllers. So they're actually 900 watts. I'm estimating, at 30 watt hours per mile, I would get 48 miles from this pack.

Should I just build a 36v 900w 40ah bike?
I'm serious, these packs are quite well made. I just need to know if I can link BMS packs like this as long as I take them apart every now and then and charge them individually. That would be eight packs linked in parallel for extra range.
I've been charging one pack for about 20min as of writing. It has not warmed up at all. My "36v" charger puts out 45v according to my multimeter, I hope this isn't too much.

I may also just go with a 36v 20ah. 40ah is a little overkill for commuting and some fun, but if I wanted to go explore some mountain bike trails... dang it would be nice to have that range.
 

Attachments

  • File_001.jpg
    File_001.jpg
    216.5 KB · Views: 2,667
  • File_000.jpg
    File_000.jpg
    270.9 KB · Views: 2,667
Have a look at the cells themselves and post up what they say on them. Really they should be tested to show they actually have the capacity they are claiming to have.

Cheap 18650s (if they are not fake cells) are typically low discharge and low capacity. Both point to having a larger pack as it spreads the discharge over a greater number of cells and allows for capacity loss over time (this is reduced by spreading the discharge as it stresses the cells less). Really they should also be matched to ensure they are of the same capacity and chemistry too as the pack will perform to the weakest cell and its more likely a weak cell will be identified early on (and scrapped to avoid a fireball).

Its not uncommon for 'cheap' stuff, done properly, to end up more time expensive than just forking out for decent cells constructed in a safe, robust, reliable pack. But I guess you learn more this way and the 'cheap' stuff is always an attractive lure.

Another idea would be to have two packs with a switch between them. Nice thing about this is the two packs do not have to be at the same voltage to be plugged into each other.. also can charge them independently, halving your charge time without needing higher current (more expensive) chargers. Lower the amount of energy available if one pack has an issue. Food for thought anyway. 8)
 
Hi guy, welcome!
It has not warmed up at all. My "36v" charger puts out 45v according to my multimeter, I hope this isn't too much.
I'd be watching them at the cellular level. See how everything is working with bms. Anyway,
I'm doubtful you should charge to 45v :!: Looks like they might be 10s, so 42v max.

If the 36v motor spins fast enough for ya I say give it a go. 20ah should be happy with the 25-30a draws and you can always bring the other half for longer rides. Saving money and weight as well I imagine.
 
nutspecial said:
Hi guy, welcome!
It has not warmed up at all. My "36v" charger puts out 45v according to my multimeter, I hope this isn't too much.
I'd be watching them at the cellular level. See how everything is working with bms. Anyway,
I'm doubtful you should charge to 45v :!: Looks like they might be 10s, so 42v max.

If the 36v motor spins fast enough for ya I say give it a go. 20ah should be happy with the 25-30a draws and you can always bring the other half for longer rides. Saving money and weight as well I imagine.

Thank you nutsspecial!

The LG packs have the following codes:
LGEAMF 11865
0195G141AF

I only cut the shrink wrap off one samsung pack, and the codes are well hidden. But I do see the word SAMSUNG as well as 5FY1.

I'm going to wire some of these up now.
Thank you for telling me that they should be 42v. I'll have to watch that. They are 10S 2P.

I may sell off four of these and just keep two 36v 10ah packs for my own use.
 
If you just charged a 10s pack to 45v, you just ruined it, and it will burn your house down.

Not a joke bro. Seriously.
 
If the BMS did its job, it will shut off at 42 volts. Circuit designers should assume the battery charger might be a little high, but still, it's not good. A lot of hover board batteries caught fire when charging, which suggests their BMS circuits were crap.

I bought a 48V battery a while ago and the vendor packed it with a 52V charger. Didn't find out til over a year later. Today that battery has half its original rated capacity. Could have been the charger. Could be too much sitting around at full charge too.
 
Back
Top