Hi all, 2013 BWs owner here from Ho Chi Minh City, Vietnam. I recently bought my BWs/Zuma, and would love to make sure the bike is running properly before using it as a daily rider.

The bike is a 2013 carbureted BWs/Zuma with 6k miles on it. Im pretty sure everything is completely stock after cracking open the crankcase up for the first time today.

The bike originally had a lot of vibration at the front end. I can feel the vibration with both feet and arm when I put the bike under slight load. If I open up the throttle a little more, the vibration decrease. There is like a sweet spot for vibration when I first crack the throttle, usually under 1/3 of full open throttle. The vibration is reduced a bit, and the engine ran a bit smoother after engine oil change (10w-30) and final trans oil change (80w-90). Is it normal? I've ridden a lot of Yamaha scooters and this one seems to vibrate the most. It almost feel unnatural as my instrument cluster shake violently every time I ride off from a stop.

Please help!

your belt is probably fighting to hold on the variator. start thinking about springs, roller weights, belt ride on the cvt.