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[Richard230]

Now this looks like a useful electric motorcycle. It has enough power and range to be useful, looks nice and doesn't seem to be overburdened by electronic devices. If the price was right and it could be mass produced and distributed to other countries it might have a future in the EV market:
https://electricmotorcycles.news/emgo-technology-is-not-only-a-light-electric-vehicle-developer-and-manufacturer/

[Fran K]

The power in the article and the power in the linked website are close and the battery volts times the peak current load of 200 amps are sort of close as well.  The battery voltage is 88.2 it doesn't specify if that is what makes it to the motor all the time or what.  How does it work anyway I can't tell any power fall off as battery level goes down until late in the cycle.

Not much rear frame to attach stuff.
front rotor seems larger than rear one than usual.
Kind of long swingarm?
Looks like the knees have a nice place to push up against, nice seat but rather thin on padding.
Not a particularly wide ratio transmission.
What is that a clutch lever or rear brake or regen lever?
Must be pretty heavy are not the 17 inch rear tires of that type kind of higher load than the 18 inch ones?
Is that the key right in front of where the right knee would be?  Ouch?
If that is a throtle cable I see it is quite vunerable to brush damage.

[TheRan]

Considering it has a rear foot brake and it looks like there's a clutch linkage on the motor/gearbox assembly I'd say that's a hand clutch lever. A cable throttle is indeed a strange choice, I can't imagine that and a suitable potentiometer works out any cheaper than an electronic throttle. For the gear ratios it would be nice if 1st went up to at least 50km/h for 30mph roads.

[caza]

Gearbox and small motor combo is a strange choice, but I like the looks and it seems like it was built well to its budget. But of course for now it's just a "project" so nothing more than a couple pretty pictures until it has pricing and availability.

[Richard230]

I think the article said that it had a 4-speed gearbox. I wonder where they sourced that transmission? Even my Royal Enfield has a 5-speed tranny.

[caza]

There are a lot of 4-speed transmissions around, ususally from cheap chinese bikes but the most popular example right now is the grom. (Which I think finally moved to 5-speed for 2021)

It seems to be very similar to this electric motor/transmission that denzel sells http://eastgem.net/gearbox-200.html

[Richard230]

There are a lot of 4-speed transmissions around, ususally from cheap chinese bikes but the most popular example right now is the grom. (Which I think finally moved to 5-speed for 2021)

It seems to be very similar to this electric motor/transmission that denzel sells http://eastgem.net/gearbox-200.html

That was news to me. I had no idea that companies were manufacturing dedicated transmissions for electric motorcycles.

[Fran K]

I changed my mind upon re evaluaton of the ratios it should be considered a wide ratio transmission being high is more than 3 times low.

Could 4 kw continious also be 16kw or so peak?

[caza]

Could 4 kw continious also be 16kw or so peak?

Yes that could be the case and often is.

Electric motor ratings are kind of hard to parse sometimes

Here's an example, the QS 138 90H:
https://www.aliexpress.com/item/4001245756151.html

This motor is called a 4KW motor, but it's rated at 72v 89a continuous, or 6.4kw, and its max current is 200a, which would be 14.4kw.

I heard someone say the 4kw in the name of motors has to do with some relation between KW and RPM, though I can't find a source or specifics on that. Maybe someone more knowledgeable can chime in.

That was news to me. I had no idea that companies were manufacturing dedicated transmissions for electric motorcycles.

It seems to me the transmission I linked to uses tooling/parts from an existing gas bike transmission, the molds were just modified to accommodate an electric motor. I don't think they are very popular, but I've seen videos of at least 1 streetbike and 1 dirtbike conversion using this motor/transmission in the states. I imagine you can find cheap Alibaba bikes that use this part or a clone of this, though I don't recommend it!

[TheRan]

I heard someone say the 4kw in the name of motors has to do with some relation between KW and RPM, though I can't find a source or specifics on that. Maybe someone more knowledgeable can chime in.

You're probably thinking of the kV rating for small hobby motors used in things like RC cars and drones, which tells you the motor speed in 1000s RPM per volt fed into the motor (so a 5kV motor fed with 5 volts would spin at 25k RPM for example). At least that's what I've been lead to believe, I don't actually mess around with that sort of thing.

[caza]

Yeah I think you're right it was kv ratings that are related to rpm