1 - I have always run 3 bolts in Yamaha and now KA senior, never had an issue related to three bolts. I run 6 bolts with a split ring on the 206 because you have no other choice with a split ring.
2 - The o-ring camp will say there is no difference when running and they last longer. The non-oring camp will say, even some resistance is resistance and the chains cost less. With regular lubrication and cleaning occasionally in an ultrasonic clean my non-oring chains last a season or more.
3 - I think kerbs are only part of the issue. If your track has noticeable drop offs when you drop a wheel or you have a new driver that is likely to go over kerbs or off track on a regular basis I would run something. If your track has mild kerbs and little drop off on the edges you likely donāt need a guard unless you are in the mid 80ās of higher.
I used Top Kart Aluminum Sprocket it was brand new and clutch sprocket was IAME brand new. I also had 3 bolts installed. I didnāt hit any curbs, it was raining so they were slippery.
@calebgilbert do you have any picture of the guard installed?
3 bolts with one piece sprocket is fine, even on X30. Sprocket life? RK chain, I changed every 3 or 4 races. Front sprockets every 6 months Iāve found that the chain oil is the weak link (pun intended). The wrong oil kills the chain. There is a lot of discussion on chain oil, I like Bel Ray.
