The weight of an Unladen XS

[MISTERPROFESSIONALITY]

746 watts = 1hp. So 8000W is 10.7hp
An electric motor has the advantage of having that hp on tap almost from the start. So yes, they "feel" more powerful.... and as a practical matter, yes you can get away with a lower hp electric motor. But that has limits.... 10.7 hp in place of 40hp is beyond those limits.
Just as a guess... 'cause yes, I'm an amateur at this stuff too.... 20,000W would prolly get you close to the feel of an XS motor.

I actually went into it expecting the electric XS to be much slower than the original, because all i wanted was an "adequate" bop around bike but my Honda CT125 has about 9hp and weighs half what the XS weighs....that would be woefully inadequate. Its definitely something that would be a lot more sutable for the little CT90 chassis

 

[gggGary]

This

um beauty goes about 100 pounds

 

[650Skull]

Have you read these??

https://www.instructables.com/Build-Your-Own-ELECTRIC-MOTORCYCLE/

http://www.evalbum.com/
http://www.evalbum.com/type/MTCY

http://www.evconvert.com/tools/evcalc/

https://ecomodder.com/forum/tool-aero-rolling-resistance.php

 

[funky]

I love electric bikes their great

 

[arcticXS]

Im planning on keeping it as simple as possible with a Hub motor. I found one thats 72v 150a 8000w. Thats why im researching the weight to see if my top speed is servicable with that kinda power.

Dunno about batteries and all that though. That will have to be researched next.

Actually, the weight (mass) does not affect top speed much. It is mostly wind resistance (aerodynamic drag) that matters when it comes to top speed, and just as important, range.
Weight affects accelleration and uphill speed.
For best top speed and range, something like Craig Vetters fuel economy bikes would be the solution. Maybe based on the rolling chassis of a 125 or 250 single. Narrow tires give less rolling resistance and less wind drag.
https://craigvetter.com/pages/470MPG/470MPG Main.html

 

[MISTERPROFESSIONALITY]

Actually, the weight (mass) does not affect top speed much. It is mostly wind resistance (aerodynamic drag) that matters when it comes to top speed, and just as important, range.
Weight affects accelleration and uphill speed.
For best top speed and range, something like Craig Vetters fuel economy bikes would be the solution. Maybe based on the rolling chassis of a 125 or 250 single. Narrow tires give less rolling resistance and less wind drag.
https://craigvetter.com/pages/470MPG/470MPG Main.html

That looks like a really cool project but its well beyond the scope of what im trying to do. I have a xs650 (old and nonfunctioning and beyond my ability to repair) and i was trying to think of something i could do with it rather than discarding it or selling it for parts.