Of course I did this - pas sensor

cocopeanut

1 µW
Joined
Mar 5, 2020
Messages
4
after attempting to fix I have completely destroyed the pedal assistance sensor that determines if I'm pedaling or not. what's left is three wires a blue one the yellow one and a red one. I need a quick temporary fix solution. the magnetic disk has been taken apart and it's no longer with us. Just two three wires that lead to the controller.

to make matters worse this bike has a battery that uses a keyed lock to remove it and underneath that is where the controller is so the controller is not accessible. I bought this bike at Walmart it is one of their standard models for hyper e-ride pedal-assist electric bike. And of course I did not purchase there warranty because that would make sense.
:bigthumb:
Short of going to Walmart clipping off the sensor with a very stealthy knife, is there anything I can do to get it running. I was hoping I could somehow MacGyver 3 wires to have it be constantly on while the bike is running and using one of my disconnected brake handles to cut off the engine when I wanted it to stop accelerating.

Most appreciative...

Oscar
 
Based on what you're describing, it sounds like that bike uses a totally standard cadence sensor made from a hall sensor and a magnet ring.

Easiest solution - just grab a replacement cadence sensor off Amazon/eBay/Aliexpress and wire that in.

Example: https://www.amazon.com/ZOOMPOWER-Assist-Sensor-kt-d12l-Install/dp/B079ZRRHSR

Edit: The controller is looking for pulses from the cadence sensor, not a solid signal. So, no combination of just shorting the wires together will make it go.
 
Thank you so much for your response. Since it requires a purchase of an item I was wondering if I could somehow switch this bike from a cadence sensor to a throttle?
 
To install a throttle, you need that key to remove the battery and get access to the controller, to see if there's an unused connector needing a throttle to be attached.

If you don't see that, then you get someone who understands controllers to see if there are some unused solder pads on the circuit board intended for a throttle. And if that does not pan out, then you replace the controller.

How much did they charge you for the bike?
 
$590

So I bought the sensor wheel that was recommended earlier in the post and its wiring configuration colors are brown black and yellow. However the colors off the bike that I'm going to be attaching it to our yellow red and blue. What is a match?
 
Well, if someone has a wiring diagram for the sensor you bought, and another one for the bike you have, and also confirmation that both are still wired the same way, that should do it.

Just test systematically, there are only a few possible combinations.
 
If you want to live dangerously, just touch the yellow and blue wires together a few quick times and see if the motor turns.
This could fry the controller, though, if red is not the power wire. Verify that with a voltmeter first (that red has the highest voltage to ground).
 
So I took off the sensor and rapidly touched and split apart the the blue and yellow on the controller side and the back wheel began to spin! so now I don't understand what the relationship of that relates to how I should wire this to the sensor?

is it:

from controller to sensor
Blue to black
Red to Brown
Yellow to yellow

thanks!
 
cocopeanut said:
So I took off the sensor and rapidly touched and split apart the the blue and yellow on the controller side and the back wheel began to spin! so now I don't understand what the relationship of that relates to how I should wire this to the sensor?

It shows that red is power. Then blue and yellow are signal and ground, but you still have to know which is which. Now is the time to buy a inexpensive multimeter and learn how to use it. If you had a meter, you would measure the voltage between red-blue and also red-yellow. The pair that gives you the higher value, that pair is power and ground. The lower pair is power-signal. So now you know the colors for power, ground, and signal on the controller side,

In the meantime, you post a question on amazon asking how the sensor wire colors, brown, black, and yellow relate to signals. Absent an answer, if we think that black is ground, then a first guess is black is ground. Connect that to the the wire you measured out to be ground above. Take a guess on the other two, If it doesn't work, flip them,

By the way, the amazon listing says you bought a Pedal Assist Sensor KT-D12L. Per this endless Sphere post, it has to go on the left side of the bike.
https://endless-sphere.com/forums/viewtopic.php?t=91059
 
Hi, not sure if I'm in the appropriate thread for this but my question is has anyone tried adding a throttle to a PAS-only bike, e.g. the Hyper E-Ride from Walmart? I've seen some comments on YT that suggest the controller on this particular bike does not have a throttle wire, but I am assuming someone knowledgeable about controllers might be able to advise on a replacement controller that would allow for adding a throttle without ruining the PAS. I am mechanically but not electrically inclined so am looking for someone who may have already done it or knows how to explain what model controller might work and which wires to connect, etc. Thanks!
 
Is it a two wire motor, or a three big wires and five small wires motor? Or something else?

Have you had a look at the controller to see if there are unused plugs? A throttle plug has 3 wires, one of which would have +5V on it when the bike is powered up. Typical is red/black/green, but there are other color codes.

What's the nominal voltage and power of your e-bike shaped object?
 
LV_Rider said:
Hi, not sure if I'm in the appropriate thread for this but my question is has anyone tried adding a throttle to a PAS-only bike, e.g. the Hyper E-Ride from Walmart? I've seen some comments on YT that suggest the controller on this particular bike does not have a throttle wire, but I am assuming someone knowledgeable about controllers might be able to advise on a replacement controller that would allow for adding a throttle without ruining the PAS. I am mechanically but not electrically inclined so am looking for someone who may have already done it or knows how to explain what model controller might work and which wires to connect, etc. Thanks!

Is that not illegal?
Any ole controller would suffice.

I had one of these with KT display and pas, throttle worked real good on it even though it had pas.
https://www.conhismotor.com/
 
LV_Rider said:
Hi, not sure if I'm in the appropriate thread for this but my question is has anyone tried adding a throttle to a PAS-only bike, e.g. the Hyper E-Ride from Walmart? I've seen some comments on YT that suggest the controller on this particular bike does not have a throttle wire, but I am assuming someone knowledgeable about controllers might be able to advise on a replacement controller that would allow for adding a throttle without ruining the PAS. I am mechanically but not electrically inclined so am looking for someone who may have already done it or knows how to explain what model controller might work and which wires to connect, etc. Thanks!

Not a bad looking bike for the price. Unless you already know where it's located, you're going to have to figure out where the controller is hidden. My guess is inside the downtube where you put the key in for the battery. The wiring harness coming from the motor seems to enter the frame around there. Maybe take out the battery and post some pics of what's going on down there. The other possible location is up neat the head tube, where the cable from the display enters the frame.
 
Thanks for the replies, sounds promising so far. I don't have the bike in hand yet but will post pics of the controller (it's at the top of the down tube, inside, above the battery). I guess one way to think of it is ultimately it's just a motor and a battery and the worst case scenario could be to just replace the controller, wiring and led "computer" altogether. If it ends up just being a plug and play throttle or throttle/controller that would be best. We'll see. Stay tuned.
 
I bought a pair of these yesterday and am also going to add a throttle. I'm waiting for them to arrive so I can see what connector the system uses. Then Ill get a programmable controller (that will allow me to build a stronger battery) with a decent display. Any suggestions as to which controller and display?
 
Ok, got the bike and **spoiler alert** no throttle needed. This thing is perfect the way it is. Even at lowest pedal assist, the 250w motor provides a surprisingly strong surge of power which can be effortlessly maintained by just barely rotating the pedals. I'd even say pedaling is both easier and more "natural" feeling on a bike like this than holding your legs still, and has the added benefit of helping to maintaining balance. At assist levels 2 and 3 it's almost too fast for casual bike pathing especially when others are present, but I'm sure I'm going to enjoy the full 20 mph when appropriate. I have lots of motorcycle and minibike experience and I'll admit I prefer the lower power end of the power and speed spectrum, but I am truly surprised how fast 20 mph feels on a powered bike, especially after thinking long and hard about getting the Lectric XP for it's 28 MPH (with pedaling) top speed and throttle. So far, I'm glad I didn't spend the extra money and I got a nominal (but not ineffective) front suspension as a bonus (as if spending $500 less wasn't already a bonus!).

FYI, I found the controller where it was supposed to be but now they have it behind a plastic plate that I'm sure comes out but did not loosen easily after taking out the screws so even thought I'd like to know the specs I decided to not pursue it since this appears to be the way they solved the common loose controller rattling issue reported by other reviewers so I don't see any benefit to pursuing it further. Hope this helps anyone with similar questions.
 
Excellent. My pair arrive today. Racks arrived this morning. So after installing those while the bikes charge, looking forward to a nice cold omaha ride.
 
Yeah, I'm planning on going out later today near sunset to avoid the sun here in LV but also so I can try out my backlit computer and lights! I normally don't link to products but these items are so nice and so perfect for this bike that I thought I'd make an exception since there are a lot of items out there and most people I don't think have the patience to read through all the reviews, etc. so here they are:

https://www.amazon.com/gp/product/B089ZPHST9/ref=ppx_yo_dt_b_asin_title_o02_s01?ie=UTF8&psc=1

TL;DR: 500 lumens so works as a true headlight and not just a safety light plus tail light. Both have several useful lighting modes and are USB chargeable and come with cables.

https://www.amazon.com/gp/product/B07SCQZ9WS/ref=ppx_yo_dt_b_asin_title_o02_s00?ie=UTF8&psc=1

TL;DR: NIce green backlit display and compact size with easy to read display plus it has TEMPERATURE! Haven't seen that on any other low-priced bike computers and will come in handy here in LV! Easy to install and works great!

Both items are very surprisingly high quality in feel and construction, very impressed.
 
Excellent links. Thanks. Also everyone lets not forget to add a rear safety light. The racks i ordered have great mounting points for rear lights btw. I dont BELIEVE these bikes come with more than reflectors back there. Still waiting for fedx so i cant say for certain.
 
by LV_Rider » Oct 28 2020 12:20pm

Ok, got the bike and **spoiler alert** no throttle needed. This thing is perfect the way it is. Even at lowest pedal assist, the 250w motor provides a surprisingly strong surge of power which can be effortlessly maintained by just barely rotating the pedals. I'd even say pedaling is both easier and more "natural" feeling on a bike like this than holding your legs still, and has the added benefit of helping to maintaining balance. At assist levels 2 and 3 it's almost too fast for casual bike pathing especially when others are present, but I'm sure I'm going to enjoy the full 20 mph when appropriate. I have lots of motorcycle and minibike experience and I'll admit I prefer the lower power end of the power and speed spectrum, but I am truly surprised how fast 20 mph feels on a powered bike, especially after thinking long and hard about getting the Lectric XP for it's 28 MPH (with pedaling) top speed and throttle. So far, I'm glad I didn't spend the extra money and I got a nominal (but not ineffective) front suspension as a bonus (as if spending $500 less wasn't already a bonus!).

That's the E-bike grin, glad to see another enjoying E-bikes and the thrill of fast low speed. 8)
 
Ok, I'm back. So I accessed the controller and found it is not one that comes up in any online search. In case it helps it is manufactured by a Chinese company called "Nanjing Keqiac Electric Co." And the model number begins with "KCF06". I can see it has the expected power connections, a number of smaller two-wire connectors, and exactly ONE 3-wire black connector, which based on my experience so far COULD be for a throttle but it is in use and this bike does not have a throttle. I was of course hoping for the easiest possible outcome which would be an unused and obvious throttle connector, but I am now thinking about trying disconnecting it from wherever it goes now and connecting it to a typical 3-wire Chinese thumb throttle which I am very familiar from another ebike build. Before I do (and because I don't already have a spare throttle to try otherwise I would have already tried it) does anyone else have any thoughts? Seems like at best a 50/50 proposition at this point, so before I go any further I thought I'd ask here and see if there are any other ideas.
 
Are the three wire colors in the black connector RED BLK WHT? And, did you trace where the wires go? Also, in two e-bikes that I know, the controller is secured to the frame either at the bottom end of the down tube (below the battery), or behind a panel with recessed screws. The controllers all come out, you just have to remove a few things.
 
No, they are RED, YELLOW, BLUE. So not the expected colors for a throttle. I first had the same thought but then considered the possibility that they might have just used non-typical colors, but the evidence seems to be mounting that there is probably no external throttle connector on this controller. Now, I guess the next avenue could be opening it up (I've already got it out of it's location in the top tube behind a plastic plate and visible) and seeing if the board has unused throttle terminals. Any further advice or other ideas?
 
RED, YEL, BLU... Brakes?
 

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