Scooter vibration + Belt

[Deejays50]

Hey guys,

I finally decided to figure out why my scooter vibrates like crazy at higher speeds.

My scooter is an 08 Agility 50

I did not modify this scooter myself but it does have an aftermarket CDI, Polini Variator, and a malossi clutch.

The belt is a Kymco Bando belt.

When I had the engine running and gave it some gas I noticed the belt was vibrating up and down like a sine wave and thats when the noise started.

My question is, should I buy the stock Kymco size belt which (from research) is 729 17.7 30 ?

Or should I go with a longer belt?

Anyone have some suggestions?

Thank you much in advance.

[MotoRandy123]

Thats belt slap. Some of the Vespa's have a big pulley in the middle to keep it from happening;


Not sure there's anything else you can do about it. Resonances in the system cause it so any change
could make it better or worst...

[Deejays50]

So a newer tighter belt would not change anything?

[de-dee]

have you measured your belt,. I have three belts and they are a little different size , each one of them,.  one of them is 6 mm. longer then the others,.  but I must say the more miles I put on my scooter,. the smoother it runs ,.   32,000 km. and running

[Deejays50]

have you measured your belt,. I have three belts and they are a little different size , each one of them,.  one of them is 6 mm. longer then the others,.  but I must say the more miles I put on my scooter,. the smoother it runs ,.   32,000 km. and running

Whats the best and proper way to measure it?

[blue]

check and see how the rollers look and see if you have any flat spots. it might be time for a new clutch my 07 agilty got a new clutch after 4 years.

[de-dee]

  check the wifes sewing kit, look for a tailors tape,.  cross check it against a steel tape,   and measure around the outside of the belt  that will be your first #   then measure across the top of the belt thats your second # the last # is angle of belt  usually  30 degrees

[blue]

  check the wifes sewing kit, look for a tailors tape,.  cross check it against a steel tape,   and measure around the outside of the belt  that will be your first #   then measure across the top of the belt thats your second # the last # is angle of belt  usually  30 degrees

X2 the degrees of the belt is what most likely wears out frist on the belts. If so its time for a new belt.