Make your bike sound really cool with a balloon rubbing against the spokes and duct taped to the front forks. Inflate the balloon a little more or less to find the perfect sound. Vrrooom! Sounds different than playing cards in the spokes. A good quality helium balloon will last a long time if positioned properly. And you get a mini boost of turbo power when the balloon finally pops. Recorded with an iPhone 4.
![](https://i.ytimg.com/vi/3__r-1JbZ2k/mqdefault.jpg)