cam chain rattle?

the weather finally broke and I had the time for a 2 hr ride today.
while at relatively high speed ( about 80mph) i gave the throttle a twist to do a quick pass and I heard what sounded like a cam chain rattle coming from the right cylinder only. it went away as soon as I started to close the throttle.
this happened once before under the same conditions. it only seems to happen at high speed, under load in 6th gear.
I am not sure how to diagnose this as the rate of speed when this happens requires full attention to the not crashing part, so I can't 100% say it is coming from the cylinder head.

it's a 2016 SE with 21k miles on it with a recent full service which included the required valve adjustments
last time it did this was before the recent service, so i don't think its the lifters.

ghetto search pulled up earlier models with a gasket issue, but i don't think this applies to my year, or does it?

any ideas how to diagnose this?

No, the gasket issue was with the earlier 'Deep Sump' engines.

Sounds like detonation to me. What RPM are you doing when you whack the throttle open? What happens if you go down a gear or two?

What octane fuel are you using ?

I'm using US premium fuel - can't recall if it's 91 or 93 octane.
I've been hesitant to recreate the issue in case it was the cam chain not wanting to screw anything up.
usually at slower speeds I down shift when accelerating. in this situation I am in the 80-90mph range in 6th with rpm's somewhere in the 5k range when i goose it.

next time out, I'll confirm the octane and try to recreate it

thanks!

I had a loose header clamp when i bought the bike which used to sound like detonation under heavy load Solved by a new gasket and pulling the header back straight & even

I'm relieved to hear no concerns about an engine issue!
It's possible that I put in some 91 octane instead of 93 when I filled up, as I stopped at a gas station I normally don't go to.
went out today with no issues after filling up with  new gas
I'll double check the exhaust system and carry on as usual

thanks!

Chris,
I use non ethanol 89 all the time. No rattle. I’m sure that’s not your problem. Has to be something else like Jon says.