I'm using Street Twin to work from Gombak ->KLCC-> Bukit Bintang everyday, the bike is not that big but definitely bigger than kapchai or 250cc scooter. cilok is fine but you need to be patient and realise that you are not riding kapchai so you dont go for every gap. If you think the gap is not big enough just wait and let smaller bike passed you, eventually it will open up and you can move. I ride the same route with my Nmax and found the difference in commuting time is probably 1-2 mins max.

i ride my heavy ass bike (a 2005 zx6r) with a surgically repaired hand and a broken shoulder. just need to be mindful when riding. its stable when ure moving but gets a bit sketchy if u move very slowly or when ure in a stop. if i park front first i need to manually push or pull that bike from the parking spot, align it and then get on the bike. oh and make sure u wear something comfortable and easy to move also. a skinny jeans (example) would limited ur moves and can throw ur balance off.