some people say they work but I don't know. Some of the engine builders here will tell you they don't really do anything for a single cylinder either but i know the yz80's had them so you would think yamaha would of tested and made sure the boost bottle did something before they put them into production. Boost bottles help to equal the pressure for twin cylinders though and you notice the difference there just not for a single cylinder. Only way to find out what it does is run a dyno but i have never seen dyno charts for boost bottles on a blaster.