My ebike - quick walkaround

I just uploaded a couple of videos of my ebike on Youtube (mainly to just answer questions about what it looks like etc).

Specs:
20-24s (I change it all the time!) lipo, 10ah
1000w motor from ebay
74v 45a controller from zenid
Decathalon rockrider 5.3
Home made pouches

Soon will have my own custom Bluetooth micro controller circuitry, similar to Cycle Analyst but much better and cheaper.
Probably pulls 3-4KW at the moment, cant be sure until I get my ammeter wired in.
Feel free to ask any questions you may have. Sorry about shoddy camera work and rushed video

[youtube]nUIxmlxcRFM[/youtube]
[youtube]CdtbKX63BU8[/youtube]

I have a few major nit pics. I understand, it's always a work in progress. But correct these things pretty soon .

The controller in the box.

It might work now, it's winter, and you don't live in a flaming desert. But it will wear out sooner if it runs hotter. My suggestion is to remount the controller to the outsde of the box. I like the front, so when riding in the rain, my ass creates a dry spot for the controller. You can seal up the controller, and the backside of the plugs with special caulk made for rain gutters. Don't use hot glue or regular silicone. You can make a box around the controller to keep it dryer, but with vents to let it cool good.

Naked lico packs.

Yes they are in a box or bag. But they rattle around in there, and chafe holes in the packs. Then maybe, they shoot fire. You need to put something durable around them. I like the coroplast sign material, but other things also work great. Plastic storage box material, stiff Masonite, etc. Turn them into hard shell packs. It may be convenient to protect 4-6 packs per container. The key thing is make the boxes super tight, so no movement inside the box is possible. Then all the chafing happens to just the coroplast or Masonite. Packs that show silver cells on the underside may need tape there before you box them. In particular, those cells in the bags are really vulnerable. Even though I know better, I put some new packs in a handlebar bag for just one day of riding. Then, I got to replace the pack that bumped on the head tube the whole ride. The bumping cut some cells open.

I don't see a torque arm on the motor.

One day, it will loosen the nut and ruin the wiring at least. Cut wires often blow the controller. Maybe I just couldn't see what you have.

Pretty sweet looking setup you've got there, can't wait till I have a similar one :O

Yeah, they sure are fun. It's the basic setup to get into the 40 mph club on the cheap. You don't have to ride that fast all the time.

One last thing, looks like you might have more than 10 ah of battery on there. It's enough to melt a motor if you don't back off some on the rides.

So add a motor thermometer, so you know when you are getting above 250F inside there. Riding hard, 8-10 miles will be edging towards the smoke coming out.

Ventilate that hub cover too.

dogman said:

Yeah, they sure are fun. It's the basic setup to get into the 40 mph club on the cheap. You don't have to ride that fast all the time.

One last thing, looks like you might have more than 10 ah of battery on there. It's enough to melt a motor if you don't back off some on the rides.

So add a motor thermometer, so you know when you are getting above 250F inside there. Riding hard, 8-10 miles will be edging towards the smoke coming out.

Ventilate that hub cover too.

Click to expand...

Controller has high quality IRFB4110 mosfets. I was pretty suprised when I opened it up, I was expecting some nasty cheap chineese designed ones. Runs very cool in all weather, I dont use full throttle that often though, just for short runs to get me out of harms way. I always apply the throttle very gradually, usually helping the motor by pedalling.
Plus thrashing it everywhere would be very inefficiant, batterys would go from full to empty in like 10 miles. Someone doing a project like this needs some good old common sense.

Same with motor, I have checked temps several times while riding and the only time I managed to warm it up was when I was abusing it by pulling some kids round a field in my cargo trailer. It has fairly skinny phase wires, so I think the phase wires would melt before the motor does.

And us Brit's dont get much hot weather, we get about 2 weeks of hot sun per year.

I have some foam padding in that box that you probably cant see, and they are housed in a custom made battery bag, the bag is ziptied to the box. They are a pretty tight fit in there and I have ridden down a bumpy canal tow path without any damage to the lipos.

No torque arm, but it has some locking nuts that are meant to stop it from rotating, my dropouts are pretty tough on my bike and I use a massive heavy automotive grade wrench to tighten it up. I have to do it real tight anyway as I have a trailer hitch sandwiched in there and it can loosen the bolts if the nut is not done up tight enough. I might put torque arms on in future anyway, I agree its better to be safe than sorry. Budget is being streched rather thin at the moment.

My brake cables seem to be doing a alright job of stopping my handlebar bag from bashing on the stem, works for me anyway, only got a little 5ah 4s in there for my lights and phone charger. I have a decent set of front forks that absorbs some shock too.

Although I really like your suggestions and I am always trying to improve my creation, its a slow and gradual process. So "works for me" but maybe not for someone else.

As you point out, much depends on how you ride it. I will melt that type of motor every time if I wot the motor at 40 mph for more than 10 miles. If you aren't trying to cruise faster than 35 mph, you will be fine on motor heat. I've melted down motors in cold weather, so weather alone doesn't make you safe.

Same with the controller, if you don't use it, it won't get hot. It will blow next summer if you ride hard.

Damage to the lipo packs is the same thing. Fine now, but when you crash, you better have your phone handy. WE DEMAND TO SEE THE VIDEO OF YOUR BIKE ON FIRE.

But you wont get far enough for that to happen with no torque arm, if you use your throttle. Sure, those nuts held today, but tomorrow they won't.

See you later, on the how do I fix my wires thread. :lol: