Cyclamatic controller shunt mod

[aseb]

It's not the motor he's 'tuned'- it's the controller. Even i8f you get a more powerful motor it will be limited by your controller unless you modify/change it.

Where can I buy a motor for £ 100.—
Because I would like to tune this one instead of the original one which still is under warranty.

Cheers

 

[John L]

After I installed the new controller and pedelec sensor from 8Fun on my bike I was disappointed. The old controller and throttle pushed me along at 16/17 mph but the new controller and sensor topped out at 14.5 mph.

As I'm reasonably fit on the bike at this stage, I felt I was getting very little help from the motor and that I was essentially cycling a heavy bike under my own power. It got to the stage that I preferred to commute on my road bike (15 miles each way) - I'm glad to be able to do that but the prospect of cycling through the winter isn't appealing.

So anyway I decided to give the shunt mod a go. After burning the top of my finger I managed to get a lump of solder onto one end of the shunt. I have to admit that I wasn't expecting too much from the mod but after putting the controller back on the bike I went for a spin and I was very pleasantly surprised.

Using the sensor only I can hear and feel the motor still contributing at 16.5/17.5 mph. I'm not entirely sure why but this extra bit of speed makes a big difference to me. My only concern is that I may be drawing too much from the battery. For now its working well. Very simple mod that works

John

 

[NRG]

Yes, a simple but good mod. Only way to check on current draw is to fit a wattsup meter or similar in line with the battery. When I did similar on my first kit the mod gave about 10~20% more current, to be clear this mod increases power directly not speed so I suspect what you are seeing is slightly more power given overcoming drag and wind resistance and so giving a slight increase in speed.

 

[John L]

Yes, a simple but good mod. Only way to check on current draw is to fit a wattsup meter or similar in line with the battery. When I did similar on my first kit the mod gave about 10~20% more current, to be clear this mod increases power directly not speed so I suspect what you are seeing is slightly more power given overcoming drag and wind resistance and so giving a slight increase in speed.

Funny thing is that the throttle isn't that much better - not sure why that would be. There's definitely a bit more grunt when taking off - first and second power settings are now useful.

 

[aseb]

Current draw is higher when starting off (and under load like hill climbing) than when cruising so it is allowing more current then.

 

[NoToneS]

It's a mod I performed on my Cohnis motor controller a few years back however, bypassing the shunt completely as you did is not a good idea as I think you've recognised. A better way is to add a bit more solder to the pads on the cct board building up a small ramp at each end. This way will increase the current in a more controlled manner, I increased the output on mine by 10% just by adding more solder.

just purchased the cyclematic power plus where do i find this circuit? in the battery or under the pedal stem?

 

[Deleted member 4366]

It's inside the controller, which is in the compartment under the battery. To open the controller,undo the screws on the end with wires coming out and the three screws in the side. The guts will then slide out. Don't solder more than 30% of the shunt. Thank Fordulike for this:

http://www.pedelecs.co.uk/forum/technical/9183-cyclamatic-controller-mod-walkthrough-pics.html

 

[NoToneS]

thanks will have a look at walkthrough now