Sur-Ron - New Mid drive Bike

[fechter]

My Bms is what went bad,it won’t charge or run the motor but on the battery rails I get 57v and 38 percent on the battery gauge.Luna wants me to send it to them for repair,but I live on a island in Hawaii so it’s more complicated to ship surface.About 1000 miles of narly off-road over 9 months.

It might be possible to replace the BMS with something generic. Not easy but not too bad if you get the right one. The bike doesn't need the signals from the BMS to run (still works with the multi-pin connector unplugged). It just wont trigger EP mode when it gets too low.

You could also get lucky and find something on the existing BMS that's fixable, like a loose connection.

 

[Kauaiguy]

I’ve had it open as Luna wanted me to do the Bms mod to check if that was the cause (B16) but no difference,also with the small plug unplugged nothing works or with it plugged in.

 

[fechter]

The next step would be to completely disconnect the BMS and reconnect it to see if it will reset. But it might just be dead. If you were brave, you could just bypass it and run without a BMS (I wouldn't recommend this). Seems like you should be able to get a replacement BMS. I know they scrapped a bunch of defective packs but the BMSs should have been good.

 

[Paulflieg]

For me, the BMS is over too! Got a 100A BMS, taken from ebay. Charging, already works. Test drive is still pending. The multi-pin connector has only 2 wires. Red and black....? Couldn't measure anything against it, is not needed. :wink:

 

[Kauaiguy]

Got a link for the Bms,as I need one too.

 

[Paulflieg]

https://www.ebay.de/itm/312645674312

Test drive .... Everything OK, works well

 

[fechter]

The multi pin connector is not needed but will drop the controller into EP mode when the battery gets low. I think the battery fuel gauge comes from the BMS so you might lose that feature. You can use a simple voltmeter to get an idea of state of charge.

 

[Kauaiguy]

That suggested Bms looks like one of the few that will fit under the cover,thanks for the link.

 

[Paulflieg]

-ja es passt gut unter die Abdeckung!

-die originale Batterie Anzeige fällt weg. Es gibt sehr kleine Volt-displays... Ausreichend!

Der "automatische EP Mode" ist ohnehin fast gefährlich. Kein Nachteil

Es sind offenbar 3 Temp Sensoren, im Akku verbaut. Je 10kOhm! Hier ist eine einfache Arduino oder esp286 Lösung nicht schwierig..

 

[Kauaiguy]

Wish I could read that post?

 

[dirkdiggler]

ja es passt gut unter die Abdeckung!

-die originale Batterie Anzeige fällt weg. Es gibt sehr kleine Volt-displays... Ausreichend!

Der "automatische EP Mode" ist ohnehin fast gefährlich. Kein Nachteil

Es sind offenbar 3 Temp Sensoren, im Akku verbaut. Je 10kOhm! Hier ist eine einfache Arduino oder esp286 Lösung nicht schwierig..

It fits well under the lid.
The original battery display doesn't work. There are small voltage displays that work well enough.
The automatic ep mode is kind of dangerous. No advantage.
There are 3 temp sensors in the battery. 10k ohm. You could use a simple arduino or esp286 solution, not too hard...

 

[Kauaiguy]

Thanks guys for the info.What is the esp286?

 

[Paulflieg]

A WLAN capable microcontroller, like Arduino. Easy to program. Can be used for many different things. Just google it and you can see it

 

[Kauaiguy]

Does anyone know what the third wire does or reads on the charger,I know there’s + - but what triggers it
Steve

 

[elik1111]

I am considering buying a built 60V 60 ah battery. Is it going to work with the stock X controller?

 

[Paulflieg]

Does anyone know what the third wire does or reads on the charger,I know there’s + - but what triggers it
Steve

On the battery side, nothing is connected.

 

[Kauaiguy]

Thanks,that’s what I was hoping.

 

[thoroughbred]

I am considering buying a built 60V 60 ah battery. Is it going to work with the stock X controller?

If you unplug your small connector on your stock battery, however your bike behaves in that condition should be the way it behaves with the new pack. What battery are you looking at?

 

[crazy_dave]

Hey all,I bought a used Sun-Ron with 25mi on the clock.
It would (cutout) randomly (now every ride) and after some research I thought it was the safety switches. I have removed the side stand, both hand brakes, and the tip over switch. I have also installed an X-controller; my motor is compatible with the X but it continued to randomly cutout and leave me pushing it home. Sometimes I could turn the key off then back on and It would be good to go until it cutout again. Other times I would turn the key off, flick the airswitch (breaker) off then back on and it would work. All else failed I would just let it sit until it decided to work again. Sometimes a few mins, other times it would be days before I got back to it.
Last week I switched the X back to the stock controller to see what would happen, It’s still cutting out. I cannot find a common theme as to WHY. Hard hits, fast/ slow, cold/ hot weather, does not matter. When its done it just stops. Everything on the displays are working with no error codes. It just won’t move. One thing I did notice (while pushing the bike home) was that the MPH would read 0 while pushing if it was NOT going to work. As soon as it would read MPH while pushing, it was ready to go.
I’ve been ride/ wrenching on IC dirt bikes since I was 5. However, I’m very new to eclectics and I’m outa my element. Could some kind soul please help me try to troubleshoot this issue? I love the bike but I need to be able to have faith that it’s not going to leave me stranded.
Many thanks in advance and please feel free to email me freeride772001@yahoo.com

 

[Paulflieg]

I suspect the BMS !? -> Measure voltage at battery connection! Once when it works and again when it doesn't! It should never be less than 50V! If it doesn't run, open the battery and connect B- and P- (B- is battery -) (P- is - pole on the battery connector) then give very very little gas! (Jack up the bike) this way you know whether the BMS is defective. CAUTION-DO NOT MAKE MISTAKES !! If you have no experience with Elektric, do nothing ......

 

[JuiceMeUp]

Faulty motor hall sensors - they are a spare part. Easy enough to change out
Mine had similar symptoms.

 

[crazy_dave]

Hey, TY guys for the fast replies!

I looked at the battery BMS hack and it looked straightforward. That is something that I would feel comfortable doing. Unfortunately, the symptoms do not seem right. Everything works except the forward motion lol, and no flashing or codes on the display.
O.K, Ive seen the hall sensor for sale on Luna and figured it was a wear item but had no idea what the hell it was or how to test/ replace it. There is not much info on the description. Could you please give me a dumbed down explanation of what it is and how to replace it?
I was leaning towards that sensor or the box that controls the throttle. IDK if it was my imagination or not but……. I thought that the throttle felt (jerky/ twitchy) sometimes just before it would die.
This is my problem. I can strip down and restore motorcycles/ dirt bikes with ease. It took me a long time and a lot of screw-ups to get to where I am today with IC bikes. But now its a piece of cake.
I do not know and understand all the components of electrics and how they interact with each other. I’m sure there will be a price to pay for this knowledge. But in my experience, not knowing costs a lot more.

 

[Animalector]

dodgy throttle? or perhaps broken throttle wires? it could be something simply like that.
Andy

 

[crazy_dave]

Just saw this on Luna, they are sold out of Hall sensor but are know offering electric throttle replacements that plug into the X-controller. Apparently, this is what the extra port is for. At least that's the way it looks.

Could this help me in anyway?

 

[crazy_dave]

dodgy throttle? or perhaps broken throttle wires? it could be something simply like that.
Andy

Sorry, I don't think I understand. The throttle cable itself is fine without any frying. Are there wires further down the line that I should be looking at?
TY!