I remember reading about the amount of oil that the Yamaha 4-strokes would consume on a â€œnormalâ€ basis when the RX-1 first came out. I’m now considering purchasing a 4-stroke, and was wondering if this still applies or if the issue of oil consumption has been addressed (overcome). Thanks, Ralph!
Oil consumption was really much more of an issue on the 2003 RX-1s, but field data has shown it to be far less on the later models. Like with most new products, there are lessons to be learned and the product improves with each successive year of production. Therefore, I don’t consider oil consumption to be a valid objection to the later year Yamaha three or four cylinder models.
What did Yamaha do to overcome the issues of the 2003s?Most of it was accomplished with a revised breather tube that alleviated crankcase pressure so oil wasn’t being forced through the intake and combustion chamber. A slit was added to the crankcase vent tube inside the airbox, so if in case the vent tube became blocked by ice it wouldn’t suck the oil down like the 2003s.
This can be done to 2003s as well by simply adding a 20mm slit along the tube length inside the airbox. Think of it as a â€œrelief valveâ€. A number of sleds that experienced icing of this vent line would exhibit an oil leak from the cylinder head cover gasket. In cold weather, the end of the vent line inside the airbox would become blocked with ice build up. When this happened, the crankcase pressure would rise and cause all sorts of problems, including gasket and seal leaks, along with excessive oil consumption.