cnebikes kit

[andyshirley]

A couple of months ago I purchased a 36v 500watt kit with lcd display.

I'm new to ebiking and now use my bike to commute 7 miles each way.

I'm happy enough in general with the kit. I peddle almost all the time and on the flat can get about 22mph, maybe a little more, I'm happy with that.

The lcd display sets the motor cut off speed, the max you can set it to is 40kph.

Like most people a little more oomph on the hills would be nice.............. I've been reading about various ways to achieve this............ some of the reading gets a bit too electronic techy for me though.

I can't afford to do much in all honesty, at present............... It would still be nice to know what options I might have though.

Cheapest would be a shunt mod I'm guessing? In the future though would this controller/lcd panel and motor take a higher voltage?

Best regards --- Andy ---

 

[Icewrench]

Before you add more power to that look into a good set of torque arms.

A small bit of solder added to the shunt will give more amps.
Some batteries will wear out sooner when pumping out more amps.

Most controllers can take a 48 volt battery.
When you open the controller to add some solder look at the voltage rating on the caps and the fets.

 

[andyshirley]

Cheers.

Yes I'm aware of the need for torque arms.

I've been watching and examining the mounts regularly. Seem ok for standard power system. The front forks are steel.

Planning on sorting something though, I'm a metal worker so its no problem to custom make something suitable.

 

[Icewrench]

With steel it is easy to make the dropout thicker and make the slot deeper so the axle nuts can have something to hold on to.
Then no torque arms are needed.

 

[andyshirley]

These dropouts are 3mm and have a pressed circular reccess to position the washer. The dropouts had to be filed slightly deeper to centralise the washer.

With regards increasing the battery voltage, I wont be doing it anytime soon, I'm commuting on bike to save money, so it'll be when the 36v battery dies.

Still thinking about the shunt mod though.

regards --- Andy ---

 

[wesnewell]

You can always just add more batteries to what you have now to increase voltage. Most controllers are good to 63V limited by the caps, with 68V or higher fets. With increased voltage you will see an increase in both acceleration and top speed.

 

[dogman dan]

I will bet the controller can take the addition of 12v more easily. But I have no clue if the lcd display can. Chances are it can, but it's a pure guess at this point.

Anybody out there ever overvolted this particular kit?

12v more will give you more speed, and more total watts giving better hills performance. If it ends up ruining the display, we'll help you with getting it to work without the display.

Get at least one torque arm asap. For now, be extra sure you don't have crooked washers or washers that span empty space in the dropout cups.

 

[gwhy!1]

A couple of months ago I purchased a 36v 500watt kit with lcd display.

I'm new to ebiking and now use my bike to commute 7 miles each way.

I'm happy enough in general with the kit. I peddle almost all the time and on the flat can get about 22mph, maybe a little more, I'm happy with that.

The lcd display sets the motor cut off speed, the max you can set it to is 40kph.

Like most people a little more oomph on the hills would be nice.............. I've been reading about various ways to achieve this............ some of the reading gets a bit too electronic techy for me though.

I can't afford to do much in all honesty, at present............... It would still be nice to know what options I might have though.

Cheapest would be a shunt mod I'm guessing? In the future though would this controller/lcd panel and motor take a higher voltage?

The hub you are using looks Identical to the one that I am using on one of my bikes at the mo and it a 500w 36v one :wink: I run it at 40A with out problems on 48v ( but I dont have the lcd display ) so I would say solder the shunt for a cheap and dirty upgrade, But dont put to much solder on the shunt all in one go, do a bit -test/measure do a bit more until you get upto around 40A.

 

[andyshirley]

Thanks for the advices chaps. I'm considering my options now.

I'm glad I looked into the controller bag today, I found the battery to controller wires melted, must of been a bad connection.

I have made a quick fix to keep the bike in use.

While looking at all the wires from the controller, I couldn't help but notice the wires that exit the controller to the motor are quite heavy gauge, but after the connections[wires from the motor] they are considerably thinner.

Here is a shot of the dropouts, I consider them to be ok for now, although I will be sorting some sort of torque arm.......

Also........... I have these batteries off my sons rc helicopter which he doesn't use now, so maybe I could add another 7.4 volts external to the main battery pack, which is all contained in an ali case?????????

 

[andyshirley]

I was wondering if this simple booster battery system seemed feasable to you gurus............ or have I made any schoolboy errors?

Cheers --- Andy ---

 

[999zip999]

I don't like those cheap bullet connectors and if the phase wires have extra length they make heat. So if you cut the wires shorter put some anderson on their. Will the 7.4v pack also have 10ah ?

 

[andyshirley]

Thanks for the reply,

No it wont be 10ah, I just want to use what I already have because money is tight at the moment.

So it would be a combination of the batteries in the above photo......... or maybe just the 2200mah lipo. If it would provide about 3minutes of power for the one hill on my return commute.

If I had or could afford 7.4v 10ah at the moment I would then do away with the switch and run 12series all the time.

I was going to use the switch purely because of the mismatch of ah between the 36v pack[main battery] and the 7.4v booster.

Does that make sense?

 

[John in CR]

Beef up all main power wires, the 2 battery wires, and the 3 phase wires to the motor. I wouldn't be surprised if you're losing 5% of your power just in hot wires with those all too common thin wires, which also greatly increase the chance of failure that can easily blow a controller like you almost saw first hand.

 

[dogman dan]

Those thicker wires on the controller may merely have thicker insulation. I have seen other kits with similar wire to the motor, which is thin but has higher temp insulation than the controller. It helps with cramming it all through that tube in the axle if it's skinny. But when we do upgrades to 40 amps controllers, it's common to shorten that thin wire to just enough to exit the motor axle, and replace the long run of wire with either 12 or 10 guage wire. If you do any serious upgrades in power, such as 40 amps or more than 48v, you should beef up those wires. Thick wire loses less of your power, and even acts as a bit of a heat sink if the last skinny bit is getting hot.

The battery wire likely melted as a result of a bad connection at the plug. RC hobby 4 mm bullets, Anderson 45 amp powerpoles, and several other types from the RC world work best. For sure, those really cheap automotive trailer lights bullets have gotta go. They are not good for 20 amps.

Good luck with your 7.4v boost pack. It should help a bit. If you upgrade to anderson power poles or 4mm RC bullets, you could just plug and unplug, rather than buy an expensive 20 amps DC switch. A weak cheap switch just risks the same problem with a poor contact again.

 

[andyshirley]

Thanks,
I have ordered some xt60 connectors from hobbyking. I wanted to use a switch so that I could engage the 7.4v very quickly, like whilst stopped at traffic lights. This is the switch I was thinking of..........http://www.ebay.co.uk/itm/110967971896?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649


The phase wires from the motor are 1.2mm2............... which are probably ok being in the open air??????????

Thanks again for the excellent advice.......... cheers --- Andy ---

 

[Molle]

I would be really careful with adding more voltage to a CNE-bike kit; considering their all over quality. I have a 48 v 1000 w kit and the dimensions are far to small for the currents.We have had fires and flashes, loosing connectors. When we addressed them on the problems; they just would not answer.

Further, it turns out that they claim to have CE marking on their products. This is not true; they have CE marking for an obsolete product.

Hence, gear up all cables and change the controller to minimize the risk!

 

[andyshirley]

I ended up running 12series. Just under 50v off the charger. I upgraded the wiring from battery to controller. Still running stock 22amps. All has been good for me.