New owner question: Vibration 20 to 40 mph

[RamyT]

Hi All. I’m a new 2024 C400GT owner and need your expertise. The scooter runs very smooth over 50 mpg but not in the 20 to 40 mph range. It vibrates and it feels like the pistons inside the engine anre unbalanced. Right now it has 200 miles. When I inquired, the dealer said it’s normal during the break-in and it’s because it has a small powerful engine. I have doubts. Any thoughts?

 

[jokerface]

Hi.
I've also had a slight shaking of the engine between 40-50mph since it was new, but it's not terrible. Remember, this is a single-cylinder engine with quite a lot of power. As the dealer said, there is a good chance that it will improve for you. You should try another piece to see how you feel the vibration there, but I'd be surprised if it's better than yours.

 

[RamyT]

Hi.
I've also had a slight shaking of the engine between 40-50mph since it was new, but it's not terrible. Remember, this is a single-cylinder engine with quite a lot of power. As the dealer said, there is a good chance that it will improve for you. You should try another piece to see how you feel the vibration there, but I'd be surprised if it's better than yours.

Thank you for your insights Jokerface. New York traffic and speed limits are 30 mph, and I find the shaking/vibration at this speed annoying. Otherwise, I'm very happy when I take the scooter up to 60-70 mph, very smooth.

 

[jokerface]

Thank you for your insights Jokerface. New York traffic and speed limits are 30 mph, and I find the shaking/vibration at this speed annoying. Otherwise, I'm very happy when I take the scooter up to 60-70 mph, very smooth.

There is a good chance that the engine will stall after running in. I have yet to meet an engine that did not vibrate a little in a certain range. I hope everything will be fine.

 

[jr400gt]

It certainly could smooth out as the engine breaks in, but also they call single cylinder engines "thumpers" for a reason.