ZZR 250 pinging?

Hi, Just wondering whether anyone has ever had trouble with a ZZR 250 pining on decelleration through 7000-8000 rpm?
My bike started rattling slightly after I had given up on premium unleaded after reading mixed reviews, I was origianally unaware that it was pinging, I just thought of it as a valve clearance issue which turned out to be wrong when I checked the valves and they were fine. Next I replaced the timing chain, rode it again and the noise was still there , Now after 2 tanks of premium going through it the noise, now diagnosed as pinging is gone , So for anyone who does not beleive in premium this has been the proof I need and I will never use standard unleaded again.

I ran my GPX250R (same engine) from new on normal unleaded and never had an issue for the 11,000km I had it. Would have expecting pinging to appear under load too, not under deceleration .

Ran my ZZR600 on both normal and premium and even the dreaded Shell premium stuff (which I can't remember the name of as we don't have a Shell up here any more, Optimax?). Slight performance benefit from the premium, not really enough to warrant the extra dollars. Funny enough the Optimax did better in the bike in really cold weather, which was odd, but it was good as having the carbs freeze was a pain in the arse.

Mick

Thanks Mick,
I agree that pinging would occur under load aswell which is why I went to the touble of changing the timing chain at 14,000km first because pinging never even entered my mind, but it was only fixed after getting premium fuel through the system, so I cant have any other explanation for it than it was pinging, perhaps the engine has a load on it from the engine braking? Either way it's fixed now so I am happy.

Now that I think about it there was the slightest variation in engine noise under light throttle going up hill but nowhere near as bad as on decel