Ah, I was right. It happened on my front cylinder too, and made a hell of a racket. At least it is the front - you don't need to drop the engine. It's not too difficult a job to strip down the head, but you might need a new cam shaft, depending on how chewed up the end is. If your luck's in it'll be just a new woodruff key. But you'll deffo have to replace the pulley nut - they're single use only, and need a special tool to loosen and torque up. I got a bloke to make one for me. Or you could just take the head to your dealer and ask the mechanic to loosen/tighten them for the price of a pint. The valve gear's probably ok.

You live, I learn. Good luck getting it sorted. I still maintain that they sound like a bag of spanners, even when they're running well! :lol:

bugger.

Well that will be the camshaft shagged then wont it?



This bill is going to be expensive. joy.

Cy

found this -- this morning!!!!!!!



looks like we similar problem Cy:puzzled:

Must be catching huh?
That sucks Dave.
Hopefully yours is just the key that is smeared and no more. How's the keyway?

Im worried mine may be more than even the camshaft as i can turn it a little less than 1/4 of a turn, so maybe the valve stems may be bent too. yikes.
Then, hopefully the piston isnt damaged......

I have this gut feeling that when the guy fitted the restrictor kit he may have dropped something into the cylinder by accident and never said.

Now if only my cylinder head would come off so i can check....lots of stuck bolts and no blow torch.

The irony is that i bought this bike to be a reliable daily rider... i spose i should laugh.

Snap!



hehe.

Also....

and...



Luckily its not bent.

unfortunately, it will be bent, not a lot maybe, but it will start to wear the guides giving you higher oil consumption.
It also wont be seating perfectly, so you'll get blowby under power, and lean-mixture banging and spluttering if you shut the throttle at higher revs.
Check the seating by making sure the valve is shut and pouring a little petrol in the head - you dont want any leaks into the inlet tract at all.
It looks like the pulley allowed the cam to move rather a lot.

Just checked it and it seals pretty good. no leaks
I see what you mean tho. It has been spluttering pretty badly and popping on decelleration..
Also the plug read as mega lean

Is it worth spending the £40 on a new valve or should i look for a used one?

What could cause all of this to happen? just wear and tear?