OPT, You mentioned they rarely fail... I got the bypass out of a tad of paranoia after reading a few posts in general on the net... The idea of it failing ain't pretty and likely not cheap. But I also have typically believed in the old "If it ain't broke, don't fix it". Now that I own a kit with block-off plate and a dummy pump shaft to go in, along with a new throttle cable, it sounds like I also need to plug of the oil return tube inlet to the motor if I understand correctly. Just a standard pipe-thread plug?

And 40:1 is OK? Not sure if I am looking for trouble or not if I try the by-pass...?? What are the pros & cons of it? Is it easy enough to install if you take the airbox out of the way? I was also told the pump should come out, but may not and it wouldn't be the end of the world... now wondering about the whole thing. Just cringe over the idea of it failing all of a sudden. Thanks, - Doug

 

You don't have to remove the oil pump if you premix,BUT if you have a block off plate you can.It just pulls out along with the oil pump bushing and gear and shims(make sure you get the small washer at the pump end) The small elbow fitting on the cylinder is pressed in, some guys have just capped off the end and epoxied,others have heated and pulled the elbow out and tapped out for a sealing bolt. 40:1 ratio is plenty enough for this low compression engine!We went to 32:1 ONLY on the KTM high compression 2-strokes!! The variable oil pump overall is probably leaner than 40:1,more like 50:1 ratio! But I always just checked that the pump worked first and told customers they could always use a little oil in the tank if they were worried! But a lot of people don't realize that TOO much oil is almost as bad as NOT enough! Just fouls out plugs and lowers the ability of the gas to detonate properly. OPT