XR400 Top end metalic tapping only when engine is hot?

[SillyMe]

Hi!
I have new oil change 10/40 semi, set the valve clearances and can hear them ticking nicely when the engine is cool and hot, the problem is that when the engine gets hot and the oil runs thin I hear another metallic tapping from the top end of the engine.
I noticed when I set the valve clearances that the front right exhaust rocker moves very slightly from right to left just as much as it moves up and down by 1/10th of a milli. I doubt if it's this though.
Any ideas?
Thanks!

https://img836.imageshack.us/img836/1206/dsc00012q.jpg
____________________
Once made equal to man, woman becomes his superior.
The man who says "I may be wrong, but -" does not believe there can be any such possibility
Owned and rode: Honda 100H, Honda MBX 125, Kawasaki AR 125, Suzuki RG 125 Pepsi, Honda NSR125 RK, Honda NRS 125 race bike, Suzuki GSXR 400 Bandit, Aprilia RS 125 O2, Honda CG125, Kawasaki KMX 125, Aprilia RS 125 O6, Suzuki XT225 and now Honda XR 400. ( A few scooters and other dead beats in between)

[SillyMe]

Thanks for reply.
Yeah I know it's not the valve clearances, I have set exhaust to 1/10th milli and inlet to 8/100th's nice and tight. Kicks first time and sounds great when cool.
When it get hot I get a metallic tapping from the top end.
I was wondering if it had something to do with the decompression system.

It's not too serious I hope just anying.
____________________
Once made equal to man, woman becomes his superior.
The man who says "I may be wrong, but -" does not believe there can be any such possibility
Owned and rode: Honda 100H, Honda MBX 125, Kawasaki AR 125, Suzuki RG 125 Pepsi, Honda NSR125 RK, Honda NRS 125 race bike, Suzuki GSXR 400 Bandit, Aprilia RS 125 O2, Honda CG125, Kawasaki KMX 125, Aprilia RS 125 O6, Suzuki XT225 and now Honda XR 400. ( A few scooters and other dead beats in between)

[SillyMe]

Just checked the valve clearances again and the problem persists, so i guess I could have a worn cam or rocker because when I set the valve clearances the loose point of the clearances are off set.
____________________
Once made equal to man, woman becomes his superior.
The man who says "I may be wrong, but -" does not believe there can be any such possibility
Owned and rode: Honda 100H, Honda MBX 125, Kawasaki AR 125, Suzuki RG 125 Pepsi, Honda NSR125 RK, Honda NRS 125 race bike, Suzuki GSXR 400 Bandit, Aprilia RS 125 O2, Honda CG125, Kawasaki KMX 125, Aprilia RS 125 O6, Suzuki XT225 and now Honda XR 400. ( A few scooters and other dead beats in between)

[Frost]

What oil have you put in?
Just in case you didn't know, a leaking exhaust header sounds just the same as a tappy valve. Happy tappets tap a bit, totally silent ones are something to be wary of. If the tapping gets louder when warm i would suspect too thin and too little oil when warm.