Valve guides PJ, also wrong on all other accounts.
OK, be a bit more specific
You mean you can heat up only the part of the head holding the guides, plus not get any vibration onto the seats?
Guides are driven in from the spring side, than means the seats face down.
Aluminium expands about 6 times further than 'steel'
Heard of gravity?
Too hot, not good.
Some motors are worse than others
Suzuki valve seats WILL fall out around 450f when you re-fit guides, it's why Suzuki tells you to press them in, plus, they don't supply 'standard' OD guides (you ream head 0.5mm)
Honda guides with wire circlip, drive them too deep and the circlip cracks them very neatly (sometimes from the factory, even in last few years)
Honda guide with flange, drive too deep and flange bottoms out, then, the oil seal groove shatters.
I've repaired hundreds (if not thousands ) of different cylinder head when people did it them selves because it's so 'easy'
Just about anyone can 'do' a cast iron car head, air cooled bikes are completely different
![Roll Eyes ::)](http://forums.sohc4.net/Smileys/default/rolleyes.gif)
Maybe you just get lucky, maybe GOD is on your side, maybe your just FOS?
Instead of telling how great you are, how about some real information?