Here you can see where the rocker snapped (top left)

Here you can see how loose the belt is. Is it normal?

Here you can see the damage to the head cover! Powerful stuff...

Here is the "bad guy"...

Here is another view where you can see better where the rocker broke and the damage on the head as well (bottom right)...

Enough, 'cause it is too painful to watch...

So, it's a closer that snapped. Hmmm...do the timing marks on the pulleys still align?

Great question, but do not have the answer...

If they do not, does it mean that a tooth slipped?

The guys who replaced my belt shims will check the bike, but what are the questions I should ask to make sure I understand this was (or was not) caused by a poor belt tension job?

Does the belt tension seem ok in my pics?

I'm probably totally wrong since no one else seems to have suggested it, but wouldn't the belt slacken with a broken rocker anyway?
I mean, if you don't have the valves, rockers etc in contact with each other properly (which you don't, since it's broken) then the cams will move round a tad, thus loosening the belt.
The way to tell is if the timing marks still line up or not when you turn everything into alignment.
I would have thought this was a symptom rather than a cause, because if the belt was fitted wrong, or too loose from fitment I would have thought it would have gone sooner.
Like I said though, I might be barking up entirely the wrong tree!

[Edited on 23-6-2005 by desmojen]

I dont think the belt would slacken becasue of the broken rocker, there are seven others in there to keep everything nice and tight. Plus the belt is tensioned by a pully arangement so unless that had moved there is no way the belt can come loose becasue of things going on inside the head. I've never done a four valve belt change but that amount of slack you have does look excessive.

Like others have said, if the engine will turn over the next thing you need to do is check that the timing marks line up then its head off time i think.

Oh, i just remembered, i have heard of a couple of cases of the main crankshaft belt pully shearing off. Not sure which bikes this happened on though.

My sympathy
Thats going to cost a few bob to put right.

Regards