thermal71

So I'm pretty new to all this electric bike stuff but find it really interesting, and I'm sure I'll be building for a long time to come. I know only the slightest bit of information and probably couldn't define exactly what a mosfet does if my life depended on it. I know electrical systems on these bicycles have to be balanced and can be very finicky and it's easy to fry stuff. I am curious as to what would happen with this particular system if I added a little punch to this bike with another 12v, 12ah battery which would take it from 24 to 36v. It seems like they either don't use controllers on this type bike because of the type motor, or it's on here somewhere, maybe integrated into the motor itself. Any thoughts as to what would happen if I tried it? Thanks in advance! Thermal71

knurly

That is mad-scientist kind of talk. Take your flashlight and add another battery to it, see what happens to something less expensive. It'll probably give you a brighter light for awhile until it gets hot and then you're in the dark again. If you don't know much about electricity, keep this in mind-

CigTech

you are better off adding the battery to get more range. If you want a 36v system then by a 36v system. That bike has a 24v controler that you will fry at 36v.

crackerdog

Have you tried plugging a 120 volt toaster into your 220volt dryer socket yet?

dumbass 

LOL, ebike motors are over volted all the time. Of course you have to use common sence when riding too. I have 2 EZips and one of them had twin motors sharing a 48v 50a controller. That controller is now running on a Wallie World bike that I mounted a spare EZip motor on. So yes I am running a 24v EZip motor with 48v pack and 50a controller. The trick is to use the extra power as needed and not overheat the motor. I have a temp. sensor connected to the top of the motor that give me a read out on my handlebar. I ride the heck out of it but keep the temp below the 150 degree range. There are a lot of people doing the same thing.

Will overvolting the motor cause damage? Lets say the motor is not likely to last as long as it would with the stock 24v setup. But these motors can be had new for around $65. Wow.....lets not worry about it.

The conversion of the Ezip to any level of overvoltage will require a new controller (about $35 to $45). You may want to add a new throttle as well. This is not a must have because most all throttles and controllers are +5v for the actual throttling. So the only reason you would want to replace the throttle is for the battery indicator lights. The old throttle is for 24v only. It is much easier to up the voltage to 48v and just don't go crazy because you can easily slip in a second pack. Of course the packs are lead and low in capasity.

Remember, if you increase the voltage for more speed you will consume more power per mile ridden. My last bike consumed .33AHs per mile with a top speed of about 16mph and averaging maybe 10mph. After conversion it consumes .54AHs per miles but that's at 26mph and averaging 17mph. Note: the top speed (26mph) is not actually the top speed. Just the top speed I have ridden it at because I only ride on forest preserve trails. And I'm not interested in speed there. I am guess a true top speed would be 30+. Also because I have blown knees and already have my surgery scheduled I do not peddle assist at all. So all #s are with motor power only.

Bob

crackerdog

Yes, people overvolt motors all the time but they have an idea of what is going on. I believe the OP is so new to this that he would have a disaster on his hands. And NO, you can't JUST up the voltage without changing the controller. OP, do some more study on the basics (youtube should have some basics) and give it a try- that's how we all learn.

dumbass 

I totally agree with you. Newbies should get their feet wet first before pushing the envelope on any system (even an EZip setup). Hence the reason reason I gave detailed information on the problem (like over heating). And explaining that I use a temp probe to monitor that heat. What kills the motor is mainly the heat. So control it and you limit your risk of failure.

Bob

CigTech

the problem is not over driving the motor, it's frying the 24v controller.

dumbass 

Actually you will never fry a Currie 24v controller by overvolting it because after '08 they made them so you can not exceed 29v. If you do they will not opperate. That's why I indicated you have to replace the controller for any amount of overvolting.

Bob

chi6er

My original ebike was a 24v 250 watt, I added another 12v and it ran faster, currently it run at 43v(four 4s Lifepo4) nominal. You need to open the controller and see what your capacitors are rated. My 24v contoller have 50v capacitor, so its good up to 50v or less.

dumbass 

Very glad to head your great success with overvolting. However, on all EZip bikes built from '09 most of the controllers was filled with a hot melt glue or epoxy. This makes it very difficult to check anything inside them. And as I explained earlier in this thread EZip installed a voltage limiter. Again this limiter is incased in epoxy. The easiest thing to do is buy a cheap new cntroller in the voltage you want t orun the motor at.......problem solved.

Bob