Never heard of that and I have no idea. Unless there's a carburetion problem making it fire every-other time. I've heard of a gas motor dieseling, but not a 2-stroke 4-stroking.
When a 2 stroke is running too rich it will fire only on alternate cycles. This is called "4 cycling" or "4 stroking". It makes a burbling sound and drops power to around half of normal.<br /><br />The fix is to get the mixture lean enough for normal operation. <br /><br />The cause might be adustments of the carbs, but more commonly it is caused by incorrect float settings or failures in the float operation in the carb(s).<br /><br />Good luck.
