A friends Bike

[mcsg]

Hey! Hoping for some direction please as this bike doesn't go.
I have take on a job for a friend. She has had this bike in storage and I've just charged the battery, charge is at 52V, the gauge says it's at Empty. The key turns on and permits 52 volts to controller. I've checked plugs and wiring and it all looks good and clean. There doesn't seem to be a fuse that I can see. The motor magnets and hall effect switches work so I imagine the motor is fine. The pedal assist plate seems to be missing, although the sensor is still there, the lights all work, brake switches work, the throttle feels fine, it has 3 speeds, I think it has an alarm perhaps. What information is required that would help me work this out. 5 volts at the throttle plug, 5 volts at the pedal assist plug, 5v to the motor wires.

 

[docw009]

If I read it right, you verified that the throttle receives 51.5V on the white wire and switched it to the yellow wire when key switch is on. The green wire shows no voltage from the controller when the the key switch is on.

The throttle should have two electrical components. One is the Hall sensor chip wth three wires" +5V power, ground, and signal. The other is the LED battery gauge with two wires connected to the switched power and ground. These are separate from each other and you should not see any voltage on the throttle wires higher than 5V,

You seem to knpw your circuits. Look at it carefully. Someone probably rewired it wrong.

 

[mcsg]

If I read it right, you verified that the throttle receives 51.5V on the white wire and switched it to the yellow wire when key switch is on. The green wire shows no voltage from the controller when the the key switch is on.

The throttle should have two electrical components. One is the Hall sensor chip wth three wires" +5V power, ground, and signal. The other is the LED battery gauge with two wires connected to the switched power and ground. These are separate from each other and you should not see any voltage on the throttle wires higher than 5V,

You seem to knpw your circuits. Look at it carefully. Someone probably rewired it wrong.

Yes, that's correct.

White has 52v all the time, yellow has 52v when key is switched on(turning on the controller), then, Red has 5v but is not connected in the throttle housing to the hall sensor( as soon as I connect it to the hall sensor the voltage switches to 17v) Green wire has 35v when key is switched on (and nothing when key off), when the red wire is connected properly to the hall sensor the voltage reduces in the green wire to 17v from 35v.

The Yellow wire at the key switch has purple and black wires from the back of the key go to the gauge. In my opinion the gauge is wrong, so that's an issue in itself, it should show higher at least half.

Where is the high 35v at the green wire coming from? Remember red wire is not connected to the hall sensor when green wire has 35v. Has to be something in the throttle touching or melted or something or back feeding through the black wire. (I wonder if the misconnection is reducing the battery voltage showing on the gauge?) It's not coming from the controller and I verified this in my picture when the green wire was removed from the controller plug. What I might do is connect the red wire to the hall sensor, disconnect the green wire from the controller and see what happens then. I'm not trying to prove anything here, just curious. If the green wire is still 17v with both the red and green connected then it's in the throttle housing somewhere that the high voltage is coming from. It's so weird because I can see the green wire connected to the Hall sensor and nothing else, it's isolated by some black heat shrink too and the black wire is also connected but the red is not connected as it must have broken off at some stage before I got the bike.

 

[fechter]

Sounds like possibly the ground isn't connected to the hall sensor. Check the voltage on the ground wire at the sensor. It should be zero.

 

[mcsg]

Sounds like possibly the ground isn't connected to the hall sensor. Check the voltage on the ground wire at the sensor. It should be zero.

You would be correct. I found that the black wire from the controller was not connected to the hall sensor, it was further down in the loom, however there was a black wire connected to the hall sensor but it was coming from the gauge. I didn't bother checking voltage there because it's a earth. So whilst trying to see this, the leg of the mosfet with the black wire attached broke off. So at least I know what was wrong now and I can wire in a new throttle and be done with it.
Thank you everyone that contributed information to help me with this issue, I do appreciate the help given. I have more of an opportunity now of convincing myself that I might just be able to help others with their electric bike problems in the area. I live in a hilly area with lots of electric bikes and the local bike shop won't touch other electric bike brands other than the one brand they sell. So, where do people buy their electric bike parts? Ebay, ALi Express, Temu?? I have only discovered recently that Ali express does have some parts cheaper than ebay so I might look there.

 

[gromike]

Easier to build an ebike than to fix one. With all those cheap ebikes flooding the market the business of repairing ebikes will explode. The problem is getting people to pay the mechanic enough to survive.

 

[mcsg]

Easier to build an ebike than to fix one. With all those cheap ebikes flooding the market the business of repairing ebikes will explode. The problem is getting people to pay the mechanic enough to survive.

That is all true. However there is not anyone in my area other than me to fix these bikes, so either the customer pays or the bike stays broken and they buy a new bike which will cost more. Pretty simple. I like it because it means something can 'be' repaired rather than thrown away which is so common in our planned obselecent society.

 

[RunForTheHills]

Some bikes are worth repairing. Probably not that one though. I understood you took on the project for the learning experience.

There are a lot of sources for ebike parts. Amazon, eBay, AlieExpress / Alibaba, and Grin for starters. Those that can order parts in a larger volume deal directly with the manufacturers.

 

[mcsg]

Some bikes are worth repairing. Probably not that one though. I understood you took on the project for the learning experience.

There are a lot of sources for ebike parts. Amazon, eBay, AlieExpress / Alibaba, and Grin for starters. Those that can order parts in a larger volume deal directly with the manufacturers.

I did and I was pretty happy with the result. The customer is buying the throttle for $13. So $13 for a spare ebike is worth it even if it is pretty horrible. She just needs it to ride around town if her other fails.

On another note, I have another bike in the workshop which the display does not turn on. I found no voltage returning to the controller so I fitted a wire to do this at the display plug and the bike works. I now need to find a compatible display. It's a KD58C, this is the number on the back 58c6a16533n0203g. I've read that there are a number of protocols, pins and some displays have to be custom built. Is this going to make it hard to find one. What is the best approach?

 

[RunForTheHills]

I did and I was pretty happy with the result. The customer is buying the throttle for $13. So $13 for a spare ebike is worth it even if it is pretty horrible. She just needs it to ride around town if her other fails.

On another note, I have another bike in the workshop which the display does not turn on. I found no voltage returning to the controller so I fitted a wire to do this at the display plug and the bike works. I now need to find a compatible display. It's a KD58C, this is the number on the back 58c6a16533n0203g. I've read that there are a number of protocols, pins and some displays have to be custom built. Is this going to make it hard to find one. What is the best approach?

That display seems to be available from a lot of sources. But if you can't find a particular display to match your controller, the usual approach is to replace both the display and the controller.

 

[mcsg]

That display seems to be available from a lot of sources. But if you can't find a particular display to match your controller, the usual approach is to replace both the display and the controller.

Yes, it is, however, like I said the protocols might be different etc. I'm not all that sure what I'm talking about here really, because I'm still learning. From what I've read, even if I get the same model, it does not mean the thing will work due to wiring, connectors protocols, controller differences apparently. Should I be looking at the controller model to match the display? Would that be a better approach? The price of these displays go from $20 to $100, what am I buying that the price goes up so much? I'm just trying to make it as cheap as I can for the customer without compromising on quality, due to my lack of knowledge I have no idea on what I'm trying to buy. I mean KD58C doesn't mean a whole lot because you need to use the number on the back to verify the actual requirements, which I don't know. Thank you for your advice on buying both the controller and display as a pair. Is this the norm? I could buy anything then and I wouldn't have to be quite so worried about getting the correct one. As long as voltage and amount of wires matched I'd be ok? Would I need to consider anything else?

 

[RunForTheHills]

Genarally displays have to be matched to the controller, so yes, that is the norm. There are some eco systems like Bosch where the battery and motor all have proprietary communications protocols also.

 

[docw009]

A $10 bike computer gets your customer speed/distance. You get one PAS level with the jumper.

Is it worth a $100 gamble that an arbitrary KD58C will work with your LSW controller? I think it will, if advertised to work with LSW/Lishui, but don't listen to me. I've never seen an LSW .

If you could find a US vendor on amazon selling it, you could return it if it powered up with a comm error, Otherwise, it goes back at your expense with the chinese vendors on amazon or aliexpress, if it even goes back,
.

 

[mcsg]

An update. It seems, on a few of the stores on Ali Express, they will require you to send the code (via msg or email) that is printed on the back of the display and they then will match the purchase item with that code for you. I guess they don't want items being returned because it's a pain and also they want good reviews, so I guess it works both ways. I don't want to be stuck with the wrong item or pay the postage return, AU$85 including shipping for a compatible display and the bike gets another life. For this one I'm passing on the link to the customer to buy, then it's their problem to sort out with the vendor not mine. I am thinking that perhaps $80 for a diagnosis fee plus the mucking around trying to find the correct display is reasonable? I normally charge $60 an hour for non ebike repairs. Is that too cheap? I know there are other shops that I found on the internet in Australia charging $100 just for diagnosis, fitting parts and such is extra for ebikes.

 

[n00b]

All good questions, thank you for replying.
Motor will turn by hand only. no odd noises. No odd feelings when the wheel is turned.
This is a very small bike but I can ride it, no problems or noises, only has one gear with a 3 speed switch, which obviously doesn't do anything at the moment.

Battery has 52.2v, gauge on the display/led illuminates only the 'E' light. A bit strange.

48v battery should be 54-something v fully charged.
Could be a bad cell/ bms.
Or something else entirely different, I'm no expert.
I would disconnect the brake cutoffs, though.
Just for diagnosing. Chances a new controller and throttle might would get it going.
Have you fully charged the battery?
Dang, I'd be happy to work on bikes for a lot cheaper than that.

 

[mcsg]

48v battery should be 54-something v fully charged.
Could be a bad cell/ bms.
Or something else entirely different, I'm no expert.
I would disconnect the brake cutoffs, though.
Just for diagnosing. Chances a new controller and throttle might would get it going.
Have you fully charged the battery?
Dang, I'd be happy to work on bikes for a lot cheaper than that.

A bicycle repair business doesn't cost that much to start.
I started a bike shop in Australia with $5k in 2010, 7 years on I had saved 250k and my hourly rate then was $30. I had 90 bikes on the floor, employed nobody and had so much fun. I paid a month's rent $1K, $1.5k on parts stock and a few new cheap kids bikes, $500 on tools and a cheap stand and put $2k in the bank. Admittedly here was no other bike shop for at least 30min. I closed the shop in early 2018 to move interstate. I'm not too sure if I could do it for $5k again, perhaps 7 or 8. I'm starting a mobile bike repair business now so I don't have to work 5 days a week. Once you have some tools and a some parts and workshop stock, it's pretty easy to get going, look after your customers, develop a relationship with them, be friendly, and they will look nowhere else. You must not use it as your only income initially as it might satisfy both yours and the shop's needs, but it will if you are savvy.
This van is for my local MTB trails once a week and my car setup is pretty simply.

 

[RunForTheHills]

$60/hr seems reasonable, but you know your local market better than we would. $1000/mo wouldn't have rented much of a shop in California, even in 2010. I was paying about a $1/sq ft for an industrial space in SoCal back then.

I think if someone spends $2k+ to buy an ebike, they won't balk at a $300 repair as much as they would for a $500 analog bike.

 

[mcsg]

$60/hr seems reasonable, but you know your local market better than we would. $1000/mo wouldn't have rented much of a shop in California, even in 2010. I was paying about a $1/sq ft for an industrial space in SoCal back then.

I think if someone spends $2k+ to buy an ebike, they won't balk at a $300 repair as much as they would for a $500 analog bike.

It was an old service station(gas station) that was rumored to be pulled down in 2 years and the owner let me have the low rent and I looked after the place until that time. It gave me the exposure I needed to get started. The beauty of the site was that it was at the local rail trail head,(rail to trails, I think you call them in the USA) and many riders passed by so called shop each day. When I moved after 2 years people took a while to find me again.

Well, it's a hard thing to gauge your worth, some may see it(your opinion of your worth) as expensive, others may see it as reasonable and like you say the local market/demographic is the key. I feel ebikes demand an additional different set of skills to a bike mechanic, specialized experience and that experience is 'worth' even more as there are less people available to do this kind of work. So, I think $60 for regular bikes and $80 for ebikes makes sense in my head.

 

[RunForTheHills]

Even in California not many shops will work on an ebike unless it is a brand that they sell. The ones that do are few and far between. Ebikes have the same drive trains and brakes as regular bikes in addition to the motor, controller, display, and battery. The maintenance is pretty much the same. A mid-drive will wear out the chain, cluster, and chainring much quicker though. Building wheels with a hub motor has some special considerations, but there is plenty of documentation online. Check out Grin's website, ebikes.ca.

I was in a different business, but it was a service business. In the beginning you take all the business you can find. Then as your reputation and customer base grows, you raise your rate until you feel you are being compensated correctly for your time.

 

[mcsg]

Even in California not many shops will work on an ebike unless it is a brand that they sell. The ones that do are few and far between. Ebikes have the same drive trains and brakes as regular bikes in addition to the motor, controller, display, and battery. The maintenance is pretty much the same. A mid-drive will wear out the chain, cluster, and chainring much quicker though. Building wheels with a hub motor has some special considerations, but there is plenty of documentation online. Check out Grin's website, ebikes.ca.

I was in a different business, but it was a service business. In the beginning you take all the business you can find. Then as your reputation and customer base grows, you raise your rate until you feel you are being compensated correctly for your time.

Some of that would be due to parts availability, training and possibly having to pay a mechanic to source parts online and I guess so many different setups. Can get expensive and then expect the customer to foot the bill. Who needs that?

Having been in the motor industry for many years as a motor mechanic, bikes are very simple and stress free for me, once I have had a few experiences I can gauge if I'm gonna like it. In the past I've found also the brakes wear out quickly, wheel bearings on cheap bikes wear out, much faster than non ebikes in my experience.

I think the way forward for maintenance is either become mobile and do repairs for others, rather than the shops or do training for people to learn how to repair and or maintain the bike themselves. I ran training courses in schools in past for about outdoor power equipment, chainsaws, lawn mowers etc for teens looking to get into the industry. Most people are non hands on thinkers these days, also, not very creative it seems and I think computers and technology has not helped with this. So for me, this is another easy 'in' for me. I think with AI in the future the 'hands on' people will for a while at least find the respect they deserve.

I agree with your last sentence for sure.

 

[RunForTheHills]

AI can't turn a wrench. For now.

 

[mcsg]

AI can't turn a wrench. For now.

Correct, but it will happen no doubt. But it will be one of the last industries to die because, being mobile, robots can't drive and fix stuff..........yet.

 

[RunForTheHills]

Correct, but it will happen no doubt. But it will be one of the last industries to die because, being mobile, robots can't drive and fix stuff..........yet.

Lol! Bad news on that front, AI can drive. Waymo is an example. I do like the mobile mechanic model though. I had an office for years and it always felt like a money sink. Although the van has expenses too. In the early years of the network consulting business companies like Novell and Microsoft wouldn't authorize you as a reseller unless you had a brick and mortar office.

 

[mcsg]

Lol! Bad news on that front, AI can drive. Waymo is an example. I do like the mobile mechanic model though. I had an office for years and it always felt like a money sink. Although the van has expenses too. In the early years of the network consulting business companies like Novell and Microsoft wouldn't authorize you as a reseller unless you had a brick and mortar office.

Haha! Yeah I know and trucks too over there. I feel a bit sorry for the flatbed truckers. But, both fix/repair and drive is what I meant. In the UK mobile mechanics for cars, trucks and bikes is very popular. In Oz it's kinda up and coming for bikes but there are heaps of mobile car guys. I couldn't think of anything worse, working on stands, lying on the ground is the pits.

Shimano Australia and other stoic wholesalers in Oz don't like it. If you don't have a bricks and mortar store front, display window, sell 3 bike brands, showroom and years of experience, then see ya!! I have a friend that has allowed me his user and password to purchase shimano wholesale and I have 5 other wholesalers that liked my van idea and were willing to see how it went, I only do COD so they get paid per order, with one wholesaler they give me 3% off due to payment! It's not much but who cares. I will eventually get a van, but I'm not too sure yet, most of customers so far come to me at home because I put a call out fee of $35 on each visit, not free as a lot of guys say they do. Stuff that, driving all over the country side for $0. Ali express is a huge advantage too for parts.