I bought this folding bike from a catalogue returns outlet a few months ago, thanks to Guerney pointing it out. I got this one and the Argos £245 one for £200 the pair. This one is 24v and was sold with a known faulty battery.
First I repaired the battery - sort of. It was clear that it had been tested because the faulty cell group was already marked. Rather than put in new cells, I was able to get a replacement from somewhere pretty cheap. At 24V and 13A, it was quite weak, but OK to pop down the shops or town centre.
My plan was always to convert it to 36v, so that's what I've been doing the last few days, which has been an absolute nightmare. The previous system was a King Meter T319 LED display with Santrol 13A controller with sealed connectors. I only wanted to keep the pedal sensor, so I spent ages searching through all my stuff to find the matching connector and make adapters, only to find that the stupid thing wasn't compatible with the controller. I therefore had to remove the BB to replace the sensor, but it was the old type (not cartridge) type done up by a robot to impossible tightness.
The bit I needed to remove was the thing that's flat and like a washer with two flats on it, and it's virtually impossible to remove without some special tool that clamps in place through the BB. After a whole day trying everything I had, I finally got a solution involving two adjustable spanners, a spare pedal arm, a length of 6mm threaded bar plus various nuts and washers, and a long tube to get the necessary leverage. I should've taken a photo because it was quite a creative solution. I replaced the BB with a cartridge type so that nobody will ever have to go through that again.
The rest of it was wiring in the throttle, new PAS and LCD, all of which had the wrong connectors and/or wire lengths. I tried various speed sensors, but I couldn't get the three-wire ones to work, so I left it off, mainly because this thing had already been too much hassle.
Finally all finished, I set P2=0 in the LCD to get the speed from the motor halls for the legal cut-off, and set P4=1 and C4=3 for the legal throttle. I have yet to set the correct value for P1 to get the correct speed display and cut-off, but the display shows cut-off at 15 mph even if the displayed speed is not correct. I suppose I could set it to cut off at and show 15 mph at say 18 mph by choosing the corresponding P1 value. At 24v and 13A, it only does 12 mph, anyway.
Like all these bikes, the gearing is OK for pedalling up to about 12mph, and you can go up to 15mph if you like spinning. The very low gearing compensates a bit for the low power when hill-climbing. The KT control system, as ever, is perfect, apart from the relatively low power and speed of the bike. It's just about worth swapping over to KT, just for that if you're a discerning rider.
Now comes the main purpose of this project. For £89, including delivery, you can get exactly the same battery in 36v 10Ah version from PSWPower, which is what I've ordered. The KT controller should seamlessly adjust itself between 36v and 24v, depending on which battery I insert.
Check out PSWPower for very cheap batteries of all types:
pswpower.com
Total cost so far:
Bike £100
KT controller, LCD4, throttle and PAS around £60
BB £6
24v battery £100
36v battery :£89
Total £354.
Photos of bike. I shifted the battery down and forward a bit on the rack fixings:
First I repaired the battery - sort of. It was clear that it had been tested because the faulty cell group was already marked. Rather than put in new cells, I was able to get a replacement from somewhere pretty cheap. At 24V and 13A, it was quite weak, but OK to pop down the shops or town centre.
My plan was always to convert it to 36v, so that's what I've been doing the last few days, which has been an absolute nightmare. The previous system was a King Meter T319 LED display with Santrol 13A controller with sealed connectors. I only wanted to keep the pedal sensor, so I spent ages searching through all my stuff to find the matching connector and make adapters, only to find that the stupid thing wasn't compatible with the controller. I therefore had to remove the BB to replace the sensor, but it was the old type (not cartridge) type done up by a robot to impossible tightness.
The bit I needed to remove was the thing that's flat and like a washer with two flats on it, and it's virtually impossible to remove without some special tool that clamps in place through the BB. After a whole day trying everything I had, I finally got a solution involving two adjustable spanners, a spare pedal arm, a length of 6mm threaded bar plus various nuts and washers, and a long tube to get the necessary leverage. I should've taken a photo because it was quite a creative solution. I replaced the BB with a cartridge type so that nobody will ever have to go through that again.
The rest of it was wiring in the throttle, new PAS and LCD, all of which had the wrong connectors and/or wire lengths. I tried various speed sensors, but I couldn't get the three-wire ones to work, so I left it off, mainly because this thing had already been too much hassle.
Finally all finished, I set P2=0 in the LCD to get the speed from the motor halls for the legal cut-off, and set P4=1 and C4=3 for the legal throttle. I have yet to set the correct value for P1 to get the correct speed display and cut-off, but the display shows cut-off at 15 mph even if the displayed speed is not correct. I suppose I could set it to cut off at and show 15 mph at say 18 mph by choosing the corresponding P1 value. At 24v and 13A, it only does 12 mph, anyway.
Like all these bikes, the gearing is OK for pedalling up to about 12mph, and you can go up to 15mph if you like spinning. The very low gearing compensates a bit for the low power when hill-climbing. The KT control system, as ever, is perfect, apart from the relatively low power and speed of the bike. It's just about worth swapping over to KT, just for that if you're a discerning rider.
Now comes the main purpose of this project. For £89, including delivery, you can get exactly the same battery in 36v 10Ah version from PSWPower, which is what I've ordered. The KT controller should seamlessly adjust itself between 36v and 24v, depending on which battery I insert.
Check out PSWPower for very cheap batteries of all types:
Electric bicycle ebike Battery 36V 10.4AH Haitian Electric Bike Battery Pack Bicycle Lithium 18A BMS output 350W fits bafang tongsheng TSDZ2
Electric bicycle ebike Battery 36V 10.4AH Haitian Electric Bike Battery Pack Bicycle Lithium 18A BMS output 350W fits bafang tongsheng TSDZ2
pswpower.com
Total cost so far:
Bike £100
KT controller, LCD4, throttle and PAS around £60
BB £6
24v battery £100
36v battery :£89
Total £354.
Photos of bike. I shifted the battery down and forward a bit on the rack fixings:
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