KU93 Controller- In Control or Not

[Hurricane]

Since building two new bikes for me and the Mrs to use mainly for leisure we are really happy with them but thought we missed the permanent pedelec assist power we had on our previous bikes.

I built them with the KU120 controller and Bafang BPM motor. The pedelec on this controller drops off after 10mph and then all you have is throttle. We rarely go over 15 mph unless its freewheeling down a hill but liked the pedelec assistance for cruising at 14-15mph.

I decided to buy two KU93 controllers from BMS Battery and they arrived yesterday. Great service from them as they arrived 8 days after ordering. Fitted the KU93 controllers and wend out for a test today.

Not impressed. You have no control over the speed. The pedelec just wants to keep giving more and more power until you can't pedal fast enough. You literally have to stop pedalling let the speed slow down then pedal a bit until the cadence is too high and stop pedalling again.

This might be okay for commuting but for leisure use I feel it is too much power and you have no cruising control. we like to do a fair bit of pedalling

Has anyone else found this with the KU93 controller?

 

[Deleted member 4366]

S

Not impressed. You have no control over the speed. The pedelec just wants to keep giving more and more power until you can't pedal fast enough. You literally have to stop pedalling let the speed slow down then pedal a bit until the cadence is too high and stop pedalling again.

This might be okay for commuting but for leisure use I feel it is too much power and you have no cruising control. we like to do a fair bit of pedalling

Has anyone else found this with the KU93 controller?

That's it, and the three-speed switch nor the speed limiter has any effect on it. i don't think that the software guys ever ride the bikes with their programming, otherwise they'd see it straight away.

Eventually I'll finish my interface that will overcome this problem, but for now one solution is to add a cruise control like I made. It works on the throttle so that you can dial i the speed that you want to go at and it's very good when you get used to it. I have them on all my bikes now. It costs about a fiver and you can get all the bits from Maplin and takes about 5 minutes to make and 10 minutes to install. You need brake switches otherwise it'd be potentially unsafe. There's a schematic in the Beastamatic thread.

 

[Hurricane]

That's it, and the three-speed switch nor the speed limiter has any effect on it. i don't think that the software guys ever ride the bikes with their programming, otherwise they'd see it straight away.

Eventually I'll finish my interface that will overcome this problem, but for now one solution is to add a cruise control like I made. It works on the throttle so that you can dial i the speed that you want to go at and it's very good when you get used to it. I have them on all my bikes now. It costs about a fiver and you can get all the bits from Maplin and takes about 5 minutes to make and 10 minutes to install. You need brake switches otherwise it'd be potentially unsafe. There's a schematic in the Beastamatic thread.

With the KU120 controller I used to start off with pedal assist then when I reached about 12-13mph I set the throttle cruise control with a little bit of throttle. This naturally kept a steady speed on the flat and with some pedal help it did not use much battery power so I suppose would have a good range. On a hill it tries to keep that speed so gives more assistance.

Had a look at your schematic and it does look very nice. Must be very similar to using cruise control on the thumb throttle but as you say I would need to have brake switches or it would be unsafe. At the moment I have an on/off kill switch on both bikes at the left grip should any unsuspecting dog/pedestrian appear in my path.

My bike has hydraulic disk brakes and the Mrs has integral gear levers on her brake levers so brake switches is a bit of a problem. The only thing we need to look out for on our local run is low flying pheasants.

Think I will change both bikes back to the 120 set up. At least that is controllable

Thanks again d8veh for you input.

 

[Scottyf]

I found the same. The power was to linear on the pedelec function.
Decided to get rid of it in the end and just use throttle. Found it much safer.

 

[NRG]

Its not just the KU controllers that behave this way, the LDZS ones and all of the xeicheng based controllers seem to work in a similar way.