A legal Bafang BBS01B mid-motor rated by the manufacturer as 250W - it's permanently etched on the motor by Bafang. It's legal, it'd be legal even if he increased the controller's limit to it's maximum of 20A using the programming cable and software.
So a fully charged 36V battery is 42V and you have stated 20A controller (continuous?) that is 840W peak current. 3.5x the so called legal wattage. To produce 80Nm that is probably at 20A similar to the Tongsheng.
Again this is just calling 15.5mph a 250W motor its is utterly meaningless and would never stand up in court. It's no different to the dieselgate situation where people assumed their cars were legal until they weren't and they were producing far more emissions than they claimed. How is anyone going to claim in court it is a 250W motor when tested to over 800W continuous operation?
I was a compliance officer dealing with European certification and much of it made no sense and many things were overlooked. I'd be lying if I said I wasn't surprised when many of the Chinese products we imported got through certification. People seem to assume certification means everything is checked, it isn't only a subset of checks are made to that standard. Just because Bafang certified its motor under the legislation doesn't mean it can happily use 800W legally.
So basically you believe a 800W motor is actually a 250W motor because they have put a rating label on it that says 250W? However you believe a 400W motor is less legal because someone hasn't put a 250W rating sticker on it? So someone riding a 400W ebike should have their ebike stopped and confiscated because of incompetent and corrupt legislation that makes zero sense.
I couldn't stand up in court and pretend that Bafang motor is 250W especially if they showed me it drawing 800W of power. Why is my Tongsheng less legal despite pretty much having identical power characteristics (if limited to 15.5mph) especially if I stuck a 250W sticker on it?
Whatever the legal interpretation of that motor the one thing it certainly isn't is a 250W motor. Surely no one is going to argue that a sticker over-rides the real evidence of what that motor draws in power. If someone says a 1500cc engine is legally a 500cc engine then so be it but it's still very much a 1500cc engine in the real world away from the fantasy legal world.
I would still say that motor is illegal just overlooked legally like many other ebikes. I guess you would have to send data showing it consuming possibly over 800W of power to the correct authorities and request it's legal status for use on UK roads. I'm not convinced the result would come back saying it would be legal to do so.
Also I now remember the BBS01B because its the model used for those widely distributed stickers for motors. Aliexpress etc. It's like because Bafang managed to slip through the certification it's what they are all re-labelling their 500-1000W mid-drive motors as. So its like every mid-drive motor out there be it Tonsheng, Bafang or whatever is a Bafang BBS01B just to get the 250W rating. Many of which will actually be less powerful than the BBS01B such is the farcical nature of the certification.
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