RG150 Racer piston relacement - how often?

[Jase W]

Its been a few meets since I rebuilt the engine in the RG, so i've started thinking about doing a piston replacement. I'm just after a general rule of thumb as to how often I should be replacing the piston (number of race meets is probably the best gauge). It's done 9 meets so for (3 of which were trackdays where I had much more time on the track).

I'm thinking its probably due now? I prefer to stay on the safe side as it was rebuilt last time due to the piston letting go heh

[avgas]

Piston every 30,000, rings every 20,000, bearings every 40,000, oil-pump (unless you run premix) every 25,000

that would be the max i would do. I lost my whole motor in 24,000

[Jase W]

I am aware of how many K's to replace, but I am racing so I need to do everything sooner. I also do not have a functioning speedo so no way to record K's.

Number of race meets is the best gauge for me.

[Str8 Jacket]

That's a bloody good question!! And although I agree with Avgas to a degree it can happen alot sooner with a race bike.... Last year I did the whole Vic club winter series with no engine rebuilds and even forgot to change a spark plug. I went out this weekend with a brand new piston that had been properly worn in for just over 200k's and managed to seize it. Granted, the most likely cause is the fuel starvation to the engine but I guess what I am trying to say is that you can never be too certain with 2 smokers and I would always tend to waaay more conservative and replace piston & rings after a year/series....

[quallman1234]

Tthe best person to answer your question would be pete jones, im sure he'll be around soon.

My oppion, would be, a pistion every 1.5 - 2 Seasons, depending on how much racing is being done. Run good quality 2 stroke oil.
A crank every 2 seasons, and if you have time a pull down once and a while (Only takes a couple of nights), and check the tolerances.
If these were done, and you use quality parts i'm sure you wouldn't have too many problems.