Sakura Chopper build Controller help please

[Wads]

Hi,


I built a chopper style bike using a Sakura Shopper bike as a donor & having ridden it with no problems for about 100 miles it has developed a problem.


I’ve had no experience with electric bikes up until now so have limited knowledge & wondered if anyone could help with the following:


Where can I get a replacement controller?

I’m based in Dorset; can anyone recommend someone who could repair it for me?


The problem started initially with the bike going full throttle as soon as the battery power was turned on regardless of throttle position. Suspecting the controller I sent it off for repair only to now find the bike doesn’t run at all.


I’ve checked the throttle & brake switches, which seem fine so I’m still suspecting the controller is still at fault.


To complicate things further I used the lights, indicators & battery display unit from the Sakura & would like any new controller to be able to still run these.


I don’t know the model of the donor Sakura & have attached a picture of it in case anyone can help.


Thanks,


Wads.

 

[Stalkingcat]

Pretty much any generic ebay controller should work but you may need to figure out the hall and phase wire combination if they don't match up automatically.

What voltage is your pack and do you know how many amps you want to run to the motor? This sort of depends upon the battery you are using?

If you don't want to rely on the controller to power your lights, you could use one of these below, directly wired from your pack, to run 12v to your lights via a switch. Presuming your lights are 12v, its hard to know without details?

http://www.ebay.co.uk/itm/251625135869?_trksid=p2055119.m1438.l2649&ssPageName=STRK:MEBIDX:IT

 

[Wads]

Hi,


The battery pack has three 12v lead acid type batteries wired in series giving 36v, I’m not sure of the amps but could take it apart to see if there’s any makings on the batteries.


The motor only has two wires going to it so, although I don’t completely understand hall wires, I think this means its doesn’t have hall sensors so hopefully this will make getting connections right a little easier…it’s getting the right wires connected that worries me with a generic controller.


That’s a great suggestion for the lights, even I could manage to wire it up if I can’t get a controller that does it all. Also means I could run 12v bulbs instead of the elusive 40v bulbs it came with.


Thanks for your help, much appreciated.

 

[pdarnett]

Using one of these would be an inexpensive fix http://www.ebay.co.uk/itm/36V-800W-Speed-Controller-Box-Electric-e-Bikes-Mopeds-Go-Karts-Scooters-Brushed-/171667392495?pt=LH_DefaultDomain_3&hash=item27f82c87ef

 

[D8ve]

Nice looking build the best use of a Sakura I have ever seen.

 

[Stalkingcat]

The motor only has two wires going to it

So yep, its a brushed motor. The controller Pdarnett recommended would be the one.

 

[Stalkingcat]

If sticking with the LA battery and the controller above, then no need to worry about amps.

 

[Wads]

Using one of these would be an inexpensive fix http://www.ebay.co.uk/itm/36V-800W-Speed-Controller-Box-Electric-e-Bikes-Mopeds-Go-Karts-Scooters-Brushed-/171667392495?pt=LH_DefaultDomain_3&hash=item27f82c87ef

Hi Paul,

Thanks for the link, especially as it has some wiring info that I've got half a chance of understanding!

It says 800w but I'm pretty sure my motor is either 200w or 250w does that matter? Also, no mention of amps but I guess I can email them to find out.

As you say great price but do you know if they last ok? That said, I've been trying to get my bike back on the road for a couple of moths now so if I have to swap out the controller every now & again its cheap enough to get mobile again.

Thanks for the advice.

Wads.

 

[Wads]

Nice looking build the best use of a Sakura I have ever seen.

As long as you don't look too closely at the welds ;-)

I got the bike for £35.00 as a non runner from a customer of mine & managed to get it running (Just a very obvious broken wire). Rode it around for a while & thought this is great but looks a bit Granddad'ish so chopped it up & ended up with the chopper.

 

[Wads]

If sticking with the LA battery and the controller above, then no need to worry about amps.

Thanks again for all your help. I think I'll buy one of these controllers plus the unit for running the lights you suggested & get re-wiring.

 

[Alan Quay]

Sounds like a broken throttle. They often go full speed when they fail.

I'm in east Devon. If you want to bring it over, PM me. I have a load of spare parts in my workshop.

 

[Stalkingcat]

Yep maybe do a continuity test on the throttle ground wire or
http://www.ebikes.ca/documents/ThrottleTesting.pdf

If it is the throttle, you may or may not have blown the controller?

IF going for a new controller and haven't got time for troubleshooting, then I'd also stick a new throttle on at the same time as only cheap.

 

[Stalkingcat]

If closer than Mike, I'm in Bournemouth if you're after a new throttle?

 

[Stalkingcat]

It says 800w but I'm pretty sure my motor is either 200w or 250w does that matter?

It wont matter much to the motor, those numbers usually mean, that its most efficient running at 200-250w.
The new controller may however make you go faster than the 15mph legal limit and may get you there faster. Its up to you what you require?

 

[pdarnett]

I'd get a new throttle while you're at it. Same people. http://www.ebay.co.uk/itm/Twist-Grip-Throttle-Electric-Bike-Quad-Bike-T3-/181443282319

 

[Deleted member 4366]

There shouldn't be a need to get a new throttle. If it goes full speed as soon as you connect the battery, the MOSFETs are blown in the controller, which is a common problem.

Be careful when choosing a new controller. Most brushed ones don't have a pedsl assist function. They're throttle only for scooters. You can find them with pedal assist, but you have to hunt for them.

The battery display should be no problem, as it only requires a wire from the battery.

Are the lights 12v or 36v? If 36v, it's no problem.

 

[Stalkingcat]

Or the ground on the throttle isn't connected?

 

[pdarnett]

Sorry didn't mention that, if you want pedal sensors, that controller won't do. If you do want pedal sensing you'd need a controller that would handle brushed motors such as this maybe? https://bmsbattery.com/ebike-kit/692-ku63-65-250w-6mosfets-controllerl-ebike-kit.html

 

[Deleted member 4366]

Sorry didn't mention that, if you want pedal sensors, that controller won't do. If you do want pedal sensing you'd need a controller that would handle brushed motors such as this maybe? https://bmsbattery.com/ebike-kit/692-ku63-65-250w-6mosfets-controllerl-ebike-kit.html

That's for a brushless motor, so no good.

 

[pdarnett]

Sorry I thought" Type 3: Hall sensor and sensorless compatiable, without 3-speed switch, learning itself by a switch. LVC=30/31V(36V) 20/21 V(24V)." meant it'd work without hall sensors. Unless it's just badly worded.