Reeds

[EagleJason]

What are they? Where are they? How do i know if they need replaced? Do my machines have them? 98 Vmax 500 XT; 01 SX700F

 

[horkn]

They are in between the carburetors and the engine, just past the rubber boot. They are a vital part of the intake. On my 97 600, I had to replace then this year with more than 8000 mile on it, and what 17 years. Mine were chopping and not in good shape and making it run not so well. I might get more power with the new boyesons I put in, but even if it runs better and gets better mpg, it will help.
#2 on this pic
http://www.portyamaha.com/fiche_ima...Yamaha&category=Snowmobiles&dc=31&name=INTAKE

This is my 600, but your will be similar

 

[devinzz1]

There on your machines yes. on the 2 strokes these reeds act as a valve as to let pulses of fuel/air into the crankcase/cylinder and not back out. They are known to chip and crack on higher mileage sleds and the only real way to check them is to take em off. Depending on the mileage id replace them anyways with some carbon reed for peace of mind and a little added performance.