Search found 1524 matches

by j bjork
Sep 25 2022 10:55am
Forum: EScooter/EMotorcycle Build Threads
Topic: wr250f conversion
Replies: 117
Views: 7951

Re: wr250f conversion

I dont know what time it is down under now.
But here it is sunday afternoon, and I am patiently waiting for dyno updates :wink:
by j bjork
Sep 24 2022 10:37am
Forum: E-Vehicles General Discussion
Topic: Votol EM-100 & EM-150 controllers
Replies: 2251
Views: 273199

Re: Votol EM-100 & EM-150 controllers

No, it can happen sometimes. I think it was a long time since it happened now. I have been able to log the event, but the controller doesn't show any error. My theory now is that it looses sync, or just cut off for safety when the motor rocks back and forth. Like when the wheel hardly moves and you ...
by j bjork
Sep 23 2022 11:31am
Forum: Battery Technology
Topic: Why the BMS Doesn't Work as You Believe
Replies: 9
Views: 183

Re: Why the BMS Doesn't Work as You Believe

Just stop with this bullshit, someone might think that you know what you are talking about :evil:
by j bjork
Sep 22 2022 11:16am
Forum: EScooter/EMotorcycle Build Threads
Topic: Yamaha YZ250F
Replies: 462
Views: 39447

Re: Yamaha YZ250F

Maybe you can reach 10k rpm with a lot of FW? I think the qs138 on my ktm pulls to at least 8000rpm, and that is around 80v I think. With a lot of FW that is. I will have a talk with the water jet guy, and see if he has some suitable steel. Last time he cut these when I had specified what steel jt u...
by j bjork
Sep 20 2022 10:51am
Forum: EScooter/EMotorcycle Build Threads
Topic: Yamaha YZ250F
Replies: 462
Views: 39447

Re: Yamaha YZ250F

The only reason I changed gearing was to be able to use sprockets available to buy "off the shelf". I dont have any other benefits that I know of yet, so some kind of transmission with gear change dont make much sense to me :wink: If that is what you meant? I suppose it will have higher to...
by j bjork
Sep 20 2022 3:06am
Forum: Battery Technology
Topic: Rectifier Huawei R4850G2 48V 42~58V 3000w
Replies: 210
Views: 65451

Re: Rectifier Huawei R4850G2 48V 42~58V 3000w

I use 2 in series, it has always worked for me.
by j bjork
Sep 19 2022 11:59am
Forum: EScooter/EMotorcycle Build Threads
Topic: Yamaha YZ250F
Replies: 462
Views: 39447

Re: Yamaha YZ250F

It is amazing with such simple stuff that you can just get at a reasonable price. Nothing fancy custom made in the drive line from what it seems :o Back to my bike: I was out riding quite a lot yesterday, on a tricky track with a lot of rocks and roots. But it had some faster parts too. I am surpris...
by j bjork
Sep 17 2022 8:56am
Forum: EScooter/EMotorcycle Build Threads
Topic: Yamaha YZ250F
Replies: 462
Views: 39447

Re: Yamaha YZ250F

If it is the track version of the ND981800 it should be capable of 1350 batteryA. It looks like he is running 2 (12s) battery modules, so that should be 24s. Charged to 4,2v/cell it would be 100,8v. If he is able to pull 1350A, how much would it sag, to 80v? 80x1350=108k I think my tests on cells li...
by j bjork
Sep 16 2022 4:07am
Forum: EScooter/EMotorcycle Build Threads
Topic: Yamaha YZ250F
Replies: 462
Views: 39447

Re: Yamaha YZ250F

Doug, how do you limit the charge then? (I think you were running 24s?) Do you guard it and turn it off when it is done, or let the bms cut if necessary? I dont think I will buy one, but I am curious anyway :wink: I havent really tested the new gearing yet, it will probably be this weekend. Tyson, I...
by j bjork
Sep 15 2022 12:48pm
Forum: EScooter/EMotorcycle Build Threads
Topic: Yamaha YZ250F
Replies: 462
Views: 39447

Re: Yamaha YZ250F

Thank you :) Well, I dont really know what the motor can take. I dont even know how much phase amps I have fed it, if I even have hit full throttle it has only been for a second. You can always try to get dougf to put his bike on the dyno :wink: The higher the voltage the harder to find controllers....
by j bjork
Sep 12 2022 12:04am
Forum: Motor Technology
Topic: Nanjing far driver controllers
Replies: 351
Views: 26954

Re: Nanjing far driver controllers

I just set the charger to around 121v and the bms to start balancing a little early, at 3,9v or something.
There really isnt anything magic to it..
by j bjork
Sep 11 2022 11:10am
Forum: Motor Technology
Topic: Nanjing far driver controllers
Replies: 351
Views: 26954

Re: Nanjing far driver controllers

There is no such thing as a certain cell count IS a certain voltage.
It depends of the state of charge. Yes, 30x4,2=126, but 30x4=120 or 121,5/30=4,05 for example.
by j bjork
Sep 11 2022 9:28am
Forum: EScooter/EMotorcycle Build Threads
Topic: Yamaha YZ250F
Replies: 462
Views: 39447

Re: Yamaha YZ250F

Today is sprocket day :lol: https://i.imgur.com/wipQCHy.jpg Jt sprocket only have these kind in 14-17 tooth. Dougf told me about MXT sprockets, that has a 13 tooth. Those seems to only be available in Australia and New Zealand. Then I found these, from "France equipment" (not French equipm...
by j bjork
Sep 11 2022 8:53am
Forum: Motor Technology
Topic: Nanjing far driver controllers
Replies: 351
Views: 26954

Re: Nanjing far driver controllers

On page 25 in the manual they claim 28s "ternary lithium battery" (before that is lead acid, after comes Lithium iron phosphate battery) From what I heard 121,5v is where it trips for overvoltage, I sure hope that is correct as I plan to use one on 30s when I couldent get a 1081800 Hi the...
by j bjork
Sep 09 2022 11:59am
Forum: EScooters/EMotorcycles
Topic: Ev west battery Vespa build question
Replies: 19
Views: 469

Re: Ev west battery Vespa build question

It sounds strange if the batteries would be 1C discharge, that would mean 37A discharge if it is 37Ah capacity. I dont see much use in a car for batteries like that, more like storage (powerwall) You should have batteries that can handle 10C discharge if they are 37Ah. If these are for the drive mot...
by j bjork
Sep 09 2022 11:53am
Forum: EScooters/EMotorcycles
Topic: Best controller for QS138 V3 70
Replies: 17
Views: 2169

Re: Best controller for QS138 V3 70

Ahum, I know I have seen at least 370A drawn from the battery on my 138 70h/ em150sp combo. That is at high rpm with a lot of FW though, but at lower rpm I had at least 300bA. I don't understand how you can draw so much current. Wouldn't the BMS restrict it? And the em-150 has a max of 200a. Is thi...
by j bjork
Sep 09 2022 12:12am
Forum: EScooters/EMotorcycles
Topic: Ev west battery Vespa build question
Replies: 19
Views: 469

Re: Ev west battery Vespa build question

When I contacted batteryhookup for further info regarding max discharge ability or a manufacture's data sheet their reply was I should join their facebook group where some other random person might be able to answer the question. :confused: Ya ... I'm weird but ... No thanks. Thing is with those ev...
by j bjork
Sep 08 2022 10:40am
Forum: Motor Technology
Topic: Nanjing far driver controllers
Replies: 351
Views: 26954

Re: Nanjing far driver controllers

I think there is some info about temp in the manual, and you can probably see the max temp in the program.
Anyway, it is not something you should have to worry about when it comes to not braking the controller. It should automatically limit phase amps when it gets too hot.
by j bjork
Sep 08 2022 12:20am
Forum: EScooter/EMotorcycle Build Threads
Topic: Yamaha YZ250F
Replies: 462
Views: 39447

Re: Yamaha YZ250F

Thanks guys :)

That charger looks like a real find, there is a 4,5kw version too.
And cheap, a lot cheaper than my solution..

Can you adjust the output V and A?
by j bjork
Sep 05 2022 1:06pm
Forum: EScooter/EMotorcycle Build Threads
Topic: Yamaha YZ250F
Replies: 462
Views: 39447

Re: Yamaha YZ250F

Thanks :)
The crash on the mountain (27min in) looks nasty, hope he is ok :o
by j bjork
Sep 04 2022 9:24am
Forum: EScooter/EMotorcycle Build Threads
Topic: Yamaha YZ250F
Replies: 462
Views: 39447

Re: Yamaha YZ250F

A little race rapport from yesterdays ränneslätt. I had a cold that had been lurking in the background, but it broke out on Friday :? So that sure took me down, and I didnt sleep much the night before. When I got to the pit they had arranged a corner for me (according to the rules it should be a 100...
by j bjork
Sep 02 2022 2:18pm
Forum: EScooter/EMotorcycle Build Threads
Topic: Yamaha YZ250F
Replies: 462
Views: 39447

Re: Yamaha YZ250F

You could go for a setup with two huawei 48V in series with a 24V huawei. Only problem is that you always have to power on the PSUs before you plug in the batterie, as the PSUs could be damaged through unequal charging of the output caps. Megmeet has also a rectifier with 72V 3kW but they have not ...
by j bjork
Sep 01 2022 7:41am
Forum: EScooters/EMotorcycles
Topic: My new electric motorcycle
Replies: 110
Views: 5733

Re: My new electric motorcycle

Usually when talking motor spec it is about continuous power. So if you have a 2,5kW continuous motor, you could easily get 10kW peak power. If you do, you could call it a 10kW bike and not really be wrong.. That is probably what is happening, you have a controller suitable for a 2,5kW continuous mo...
by j bjork
Aug 30 2022 12:37am
Forum: Motor Technology
Topic: Nanjing far driver controllers
Replies: 351
Views: 26954

Re: Nanjing far driver controllers

You can always measure to confirm the fault code in the meantime. I suppose it means you have a short between the positive input and one of the outputs, so I would measure resistance between + and U, V, W. (I would measure - to U, V, W too) If you have a short there you can confirm that the problem ...
by j bjork
Aug 30 2022 12:21am
Forum: EScooter/EMotorcycle Build Threads
Topic: Ninja 250 "Clone" Made in China
Replies: 156
Views: 33924

Re: Ninja 250 "Clone" Made in China

What size is the motor, is it 205 50h? I think it looks bigger in the picture, maybe more like 273 40h. How much ferrofluid did you put in there? I think 10ml is recommended for a 205 50h. Amazing that it looks so fresh :) Have you seen what phase amps the app shows that the fardriver puts out? If i...