Hi Erik
I have no idea sadly.
Weight is the result of convenience. Here are three bikes that start off somewhat similar but their weight goes up with convenience;
1. 2019 Honda CRF250L
144kg kerb weight, 6sp, 7.9l fuel, 18.2kw, 875mm seat height, single cylinder.
Conveniences: zero
Off road: Awesome
On road: No wind protection, minimal range, bag on the seat for luggage, single cylinder vibes.
2. 2019 Honda CRF250 Rally
157kg, 6sp, 10.1l fuel, 18.2kw, 895mm seat height, single cylinder.
Conveniences: Medium sized Fairing and screen
Off road: Awesome - just 13kg heavier than the L
On road: Some wind protection, bit better range, bag on the seat for luggage, single cylinder vibes.
3. 2019 Suzuki DL250 / Vstrom250
178kg kerb weight, 6sp, 15l fuel, 18.5kw, 790mm seat height, twin cylinder.
Conveniences: Large Fairing and Windscreen. Low seat height. Rear luggage rack. Frame and mounts for side luggage. 12v socket. ABS.
Off road: Okay.
On road: Good wind protection, luggage ready, 480km touring fuel range, smooth twin cylinder, ABS for safety.
The choice is up to you, but To quote Ace Rothstein
"All right, I'm gonna give you a choice. You can either have the money and the hammer or you can walk out of here. You can't have both."
https://getyarn.io/yarn-clip/94fdded...d-215f9c89f96e
If you are going enduro riding close to home the CRF250L is the obvious choice.
If you are going exploring further from home and will be riding on formed roads to get there the CRF250 Rally makes good sense.
If you are going adventure riding long distances, need luggage, using formed roads in various degrees of disrepair then the Vstrom makes sense.
None of these bikes are designed 'wrong'. The weight is the direct result of convenience. Pick your level of convenience, pick your bike. The money and the hammer.