Originally Posted by
GrandeGixxer
I was able to accomplish the 8 minute qualifiers with the Keep-Off 21-4. My runs were around 8:00-8:30 plus the half lap to get to the loop to start and I made it back to the pits each time. So I was getting around 9:00 of runtime. The motor ran good, I was able to get a pretty decent tune on it. Made it through the full 30 minute main, pitting every 7:30 and no flameouts.
What is the procedure for checking bearings, and how long do they usually last? This engine now has probably close to 3 gallons through it. I was sorely disappointed in this engine the first couple of gallons and for 6 or so races, but it impressed me yesterday. Maybe I won't make the switch to OS after all.
The Nova bearings are pretty good. They should last a while if you keep the air filters clean and run quality fuel. Once they start feeling gritty when you turn the crank or they develop a lot of play it's probably time to change them. Of course you could always tear the engine apart and inspect them that way too. The only thing that sucks is the Keep Off uses that special offset bearing and Nova is the only company that makes them. The ceramic is $85 and the steel version is still $45.