Motor recommendations for build

[mikhogl]

Hello,

What is a good motor for a bigger motorbike conversion, like a tenere 700 or ktm 790. I have started to look at axial flux 96v motors. Do you have any recommendations?
Light and small is nice, also would be nice if it could run 130km/h without any other gearing then the sprocket on the outgoing motor axel and the sprocket on the back wheel. Guess I need 25-40 kW peak and 5-15kW continuous (wild guess). Is there a axial flux 96v proven an suited for this or are there better options?

best regards

 

[bananu7]

If you can get your hands on a Yasa or similar axial flux motor, they're pretty nuts. They command much higher voltages, probably north of 300V, but on a big bike getting a controller for it it's less of a problem. The bigger problem is cost; right now there's one person selling controller + motor combos here on ES for north of $10k.

Most of us doing conversions opt for Chinese motors because of the price. Here you'd be looking at the beefiest specimen from QS, either 138-90H, 165-60H or even 180-90H. For an adventure bike, instead of looking at peak rating it would prolly make sense to aim for something watercooled so that it can operate during longer stretches. Those motors will generally happily run at 96V with no issues. That will give you the lowest cost and the most bang for your buck. Getting the power figures you're citing should be possible with either one of those 3, actually.

As far as no extra sprockets requirement, the smaller motors (138 and 165) come with internal 1:2.35 reduction drives on straight sprockets. From my experience, they work really well and allow for use of regular final drive components. If you look at specs, you can totally ignore the rated power values. 138-70H is rated at 3kW, but in my bike it has zero problems with 20kW spikes and barely gets warm; people have ran excess of 30kW through them with no issues. That being said, I'd probably look at the watercooled 90H for the reasons mentioned above. The biggest 180 one technically has enough torque to not require a jackshaft and reduction, but I'd still add one if only to move the driven sprocket closer to swingarm pivot/OEM location.

 

[Mugenski]

I found the qs180 to fit really well in a DR650. It should pull 130km/h without heat issues.

 

[dominik h]

There exists also the Sia200-50 with 1:2 reduction gear. 12kw continous and 26kW peak. If these values are like other QS values then 30kw and more can be reached.

 

[hillslayer@]

If I need that kind of power I will just skip the build part and just buy a $5000 75 mph emoto.

 

[mikhogl]

ok, nice.
Are the QS/Sia motors CE-marked? (European union) anyone that has experience of making a conversion like this legal on the streets?

 

[bananu7]

Pretty sure they're not, but at least here it's really not that big of an issue to get a conversion registered.

Might have issues with insurance later, though.

 

[dominik h]

For road legal you need much more then a CE mark on the motor.
The easiest way is to use a complete system from an already registered bike, including motor, controller, BMS, Battery and main wiring harness.

Just got a an aproval for a Zündapp Bella, from 195X, there you defenitly not need an EMC certificate.
If you have a donor bike after 1998 you probably need an EMC certificate from your bike running.
Depending on what they want exactly want to have, this can be from 500 to 10000Euro.