Next step - shunt mod

Really obvious difference when comparing 24v no mod with 36v with 1/2 shunt soldered...

...forgot to mention - there are two wires (yellow and white) which go to the throttle assembly and must be those that drive the LED's. I assume they should be connected across the battery, but am not sure of the polarity. Any advice appreciated...

I can't remember now. It's a while since I played with a Cyclamatic, but I took this photo of mine before I changed controllers. The white wire goes to a red one that comes out of a sleeve with the brake wires. The yellow one goes to another red, but I don't know where it originates, I think straight out of the controller, so my guess is that the Yellow is for the LEDs and the other must be the throttle switch.

http://i451.photobucket.com/albums/qq236/d8veh/Beastamatic/SANY01512.jpg

Thanks Yellow is at (switched) battery +volts and the LED's work happily when connected. Not using the white wire - always found the on/off button a pain on hills, when you accidentally touch it and loose inertia.

 

Opened the controller up - all looks familiar - 1/3 soldered the shunt and works well - useful extra zip. Will take it for a spin up a hill and make sure the 3 phase wires don't overheat...

I have a question. Would it be possible to build a booster pack that plugged directly into the charging port of my 24v Cyclamatic battery? The 3 prong plugs are readily available. Recognizing that it wouldn't be as efficient as directly adding cells internally to the existing battery pack, it would be pretty easy to do. Specifically, I'd like to use my 36V Makita power tool battery, which I have a dedicated charger for, reduce the voltage to 25V or so using a voltage divider circuit or buck regulator, and hook the battery up to the 3 prong plug that fits the current Cyclamatic battery pack. Thanks!

What amperage is your chargeur? That is the number of amps you will get through the charger port, or, you will blow the fuse trying to pump more than it can handle.

You can't connect a battery to the charge port because the negative goes through the charge mosfet, which will only take about 5 amps.

 

One of the pins is the common positive, which is connected tp the cells positive. The middle pin is not connected, so you could use that somehow , depending on what you mean by a booster pack.

What amperage is your chargeur? That is the number of amps you will get through the charger port, or, you will blow the fuse trying to pump more than it can handle.

1.8 amps 29V

You can't connect a battery to the charge port because the negative goes through the charge mosfet, which will only take about 5 amps.

 

One of the pins is the common positive, which is connected tp the cells positive. The middle pin is not connected, so you could use that somehow , depending on what you mean by a booster pack.

Hmm..how would it be different than the voltage/amperage that's being fed from the charger? My thought is to use a connector that's identical to the current charger connector, then positive to positive, negative to negative. But, seems like that would be to easy.....

d8veh's answer is better than mine.

What amperage is your chargeur? That is the number of amps you will get through the charger port, or, you will blow the fuse trying to pump more than it can handle.

The batteries I want to use are 3.7 amps so you are right; could be a fuse blower. I can regulate the voltage down. Need to think about regulating the current down as well?

If you are using a booster battery to achieve extra range out of the bike, then I think you will be disappointed. Every extra electronic device you put in the way of getting juice to the controller will sap power. Buck regulators are good at what they do, but will sap that juice. Possibly even the charging circuit too.

 

I assume you mean the batteries are 3.7Ah? The Cyclamatic at 24 volts is fairly inefficient, just from the virtue of its low voltage. If you want to increase range/performance on these bikes, then a 36 volt power pack is the way to go, but a 3.7Ah won't get you far, so it would have to be a higher capacity pack.

 

A few peeps have done it over the years, including myself, and IMHO is the best way to mod the Cyclamatic.

 

24 volts is just not a good voltage to work with on an electric bike, and to faff about with charger ports, buck regulators and low Ah power tool batteries is madness. 24 volt systems hail back to the days of lead acid batteries, where it was a compromise between power and weight.

 

Sorry to sound negative Steve, but I'm trying to save you huge disappointment

Edited August 23, 20169 yr by Fordulike

You need to understand how a BMS works, or maybe what it is if you don't know, and some of your comments, like " The batteries I want to use are 3.7 amps" are very worrying.

 

As I said, tell us what you want to achieve, and we can tell you how to do it. What do you mean by a booster battery? We normally refer to one as a battery that boosts the voltage, say from 24v to 30v, to get more speed and power.

Hmm..how would it be different than the voltage/amperage that's being fed from the charger? My thought is to use a connector that's identical to the current charger connector, then positive to positive, negative to negative. But, seems like that would be to easy.....

If you are using a booster battery to achieve extra range out of the bike, then I think you will be disappointed. Every extra electronic device you put in the way of getting juice to the controller will sap power. Buck regulators are good at what they do, but will sap that juice. Possibly even the charging circuit too.

 

I assume you mean the batteries are 3.7Ah? The Cyclamatic at 24 volts is fairly inefficient, just from the virtue of its low voltage. If you want to increase range/performance on these bikes, then a 36 volt power pack is the way to go, but a 3.7Ah won't get you far, so it would have to be a higher capacity pack.

 

A few peeps have done it over the years, including myself, and IMHO is the best way to mod the Cyclamatic.

 

24 volts is just not a good voltage to work with on an electric bike, and to faff about with charger ports, buck regulators and low Ah power tool batteries is madness. 24 volt systems hail back to the days of lead acid batteries, where it was a compromise between power and weight.

 

Sorry to sound negative Steve, but I'm trying to save you huge disappointment

Thanks! Really appreciate the detailed answer. For me it was more of a question of could it be done vs. should it be done! As is often the case, "could" sounds like it doesn't make sense! You know, it's interesting. I picked up the Cyclamatic, used, for around $300 US. Almost brand new according to the owner; 20 miles only in use. Who knows. But, the bike looks like new and does what I was looking for ( flattening hills) with a couple of exceptions. It stinks at flattening big hills and, until I added a suspension seat post, was a real kidney buster on bumps. I personally like the pedal assist mode (less derisive comments from my wife). I think my real need is getting more torque vs. more speed. To that end, would you recommend the shunt mod? I know I can buy a 36V 10ah battery that will plug and play for around $200 US. But I'm worried that the current gearing won't support the higher speeds that result. Not from a damage standpoint but, rather, just in being able to keep up with the pedals.

Thanks! Really appreciate the detailed answer. For me it was more of a question of could it be done vs. should it be done! As is often the case, "could" sounds like it doesn't make sense! You know, it's interesting. I picked up the Cyclamatic, used, for around $300 US. Almost brand new according to the owner; 20 miles only in use. Who knows. But, the bike looks like new and does what I was looking for ( flattening hills) with a couple of exceptions. It stinks at flattening big hills and, until I added a suspension seat post, was a real kidney buster on bumps. I personally like the pedal assist mode (less derisive comments from my wife). I think my real need is getting more torque vs. more speed. To that end, would you recommend the shunt mod? I know I can buy a 36V 10ah battery that will plug and play for around $200 US. But I'm worried that the current gearing won't support the higher speeds that result. Not from a damage standpoint but, rather, just in being able to keep up with the pedals.

The shunt mod, using the existing 24v battery, will shorten the battery's life considerably. It's very difficult to mod the shunt accurately. Too much solder and bang goes the controller. You could end up potentially drawing 2C from a battery that not only contains cheap generic cells, but was never designed for the increase in load.

 

IIRC, my original controller was rated at a nominal 7 amps. Once I carried out the shunt mod, who knows what amperage it was drawing, but I did end up constantly melting the power/key switch wiring.

 

I eventually blew the controller and switched to an external 36v controller and 36v battery. The performance increase was like night and day.

 

I do believe that some owners on this forum have used a 36v battery with the existing controller, but don't quote me lol.

Edited August 23, 20169 yr by Fordulike

The shunt mod, using the existing 24v battery, will shorten the battery's life considerably. It's very difficult to mod the shunt accurately. Too much solder and bang goes the controller. You could end up potentially drawing 2C from a battery that not only contains cheap generic cells, but was never designed for the increase in load.

 

IIRC, my original controller was rated at a nominal 7 amps. Once I carried out the shunt mod, who knows what amperage it was drawing, but I did end up constantly melting the power/key switch wiring.

 

I eventually blew the controller and switched to an external 36v controller and 36v battery. The performance increase was like night and day.

 

I do believe that some owners on this forum have used a 36v battery with the existing controller, but don't quote me lol.

Got it. Thanks. Sounds like the best action will be to buy a new 36V battery and controller and give it a try.

IIRC, Fordulike soldered all of his shunt (naughty, naughty), which is a bit extreme. You will be OK if you solder 25% of it's length. The highest you should go is 33%. I think I went to 50% on mine, which I wouldn't normally do, but it was originally only set to 12 amps, so 50% would have increased it to about 18 - 20 amps.

Completely solder the shunt... me... ok, so I went a bit overboard lol. You'll know when you go over the top, coz the motor stutters and makes weird noises.

 

Even when shunt modded correctly, it doesn't make it go any quicker, which is what's to be expected. It does however hold it's top speed better for the perception of being faster. I think mine topped out at 17mph on 24 volts.

Got it!

I do believe that some owners on this forum have used a 36v battery with the existing controller, but don't quote me lol.

I use a 36v battery with the stock 24v controller & no problems after a good few hundred miles. I should think it would handle being soldered 25% ok, I hope so coz no doubt I'll give it a try at some point .

Regards Mark

PS Top speed is approx 24mph, solely for off road use of course....

Mark

Me too. It's gnawing at me...more performance just a bit of solder away...

I use a 36v battery with the stock 24v controller & no problems after a good few hundred miles. I should think it would handle being soldered 25% ok, I hope so coz no doubt I'll give it a try at some point .

Regards Mark

Even if you did burn out the controller, you can get a 36v replacement one for about £20, or you can spend £60 and get a nice sinewave one with LCD that will give you 5 levels of assist, which is much better, plus it would smooth out and quieten your motor.

Thanks for the reply D8veh.Yeah I know I can get another controller for not much money, it's just that I'd like to keep the original & in it's original position if poss( just coz I'm like that, lol ) & I think I might struggle to find one small enough. As you know, the stock controller is tiny.

Regards, Mark

PS, May post to ask advice re repairing a controller for an Izip CB26 in the near future, lol.