What tranny oil?

[DC10]

I drained my son's Yamaha RT 100 tranny oil and put in some of my KawaChem 10W40, now it is a bit harder to shift and makes a whirring noise when the clutch handle is pulled in. Is this from the fluid? What is the best oil to use in his bike? :|

 

[DC10]

Anyone...Bueller...Bueller...????????????

 

[Rich Rohrich]

Different bikes like different oils. If the bike shifts poorly with this oil, try something else. There is no "Best Oil" .