I've had 2 cam chain tensioner springs let go on me, and when you take the bastard thing off and wind it out to its full extent, you can push the piston back in quite easily.
Believe me, when it goes, it goes. BOOOMMMMMMMMMMMMMM!
I am getting seriously irked with this whole thing now, so I am going to say my final word on it, and never speak of it again, Ever.
The Gen 1 Yamaha Fazer 1000 has a shitty little spring in the cam chain tensioner which, if it snaps, and this is a rare condition which might or might not happen to you, can fuck your engines top end in no time flat. Period. No warning rattles, no ratchets to hold all hell unleashed back, just gone.
Pop.
Take it apart and you can quite easily push the tensioner piston back in, I know this, I have done this. Your cam chain will do this in the blink of an eye, and laugh while it bends the shit out of your inlet valves
9 of them the first time
I will now be relying on a manual cam chain tensioner, and a sharp ear for rattles from that area of the engine.
And no stupid thinner-than-cheese-wire spring will hold my fate in its scrawny little coils again, the bast.
I'm off now, take it easy folks, and pray you're not as unlucky as me