ktm 520 shitting wanking twat

[MaybeGuy]

so i was pottering along last night and lost power. The engine clattered a little, and then cut out, from about 40mph to 0

I turned it over on the starter a couple of times, then it seemed to jam up. (luckily my battery is pretty fucked and wont have done it too hard)

it also jammed up on the kickstard.

I could rock the engine backwards in gear roughly half a revolution of the engine (so basically TDC is what's jamming).

i get home, and this afternoon i take out the engine and whip off the rocker cover (which the rockers are mounted in...)

with that off, it all looks normal. No valve springs loose indicating a dropped valve, yet the engine will still not turn over even though the cams arent operating the valves anymore. that rules out slipped timing.

now this would lead me to think that maybe a valve has cracked in half with part still attached, therefore stopping the valve stem being pulled through?
how likely is this? (all valve springs are the same height on the head)

any other possibilities?

i would post a few photos, but there's nothing that looks out of the norm.

i get the feeling once i take the head off i'm going to see some expensive damage

clutch and gearbox still working perfick
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Blue_SV650S wrote: it was a sh1te wheelie, but it proves that he can get it up in 3rd and can do angles. In summery, mattsprattuk is a gobby little sh1tebag, dopehead tw4t, but sadly for all of us, he probably isn't THAT full of sh1te!!
Kickstart wrote: Hi I tend to agree with Matt. All the best Keith

[Gazdaman]

Anyone need any KTM spares?

Stop wasting time and get the head off. Otherwise there'll be a million guesses, all of which will be a stab in the dark, whereas pulling the head off will give you an answer.

Gaz

[MaybeGuy]

thats the plan.
im taking the engine to a friends house so i can use his garage rather than take off the top end on a sandy/dusty/muddy driveway.
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Blue_SV650S wrote: it was a sh1te wheelie, but it proves that he can get it up in 3rd and can do angles. In summery, mattsprattuk is a gobby little sh1tebag, dopehead tw4t, but sadly for all of us, he probably isn't THAT full of sh1te!!
Kickstart wrote: Hi I tend to agree with Matt. All the best Keith

[Ed Case]

Sounds 'kin pricey, hope it ain't, best of luck.

[MaybeGuy]

got it apart after getting the cam chain split (why the fuck do you need to do this to take the top end off. seriously, its a ballache).

just a random piece of metal. not snapped off the piston, or the head. cant see where the fuck it came from. too big to fit through the inlet valves.

ill post pics later, but any ideas?

no damage to piston, bore or head other than a few impacts that removed the coke from it.
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Blue_SV650S wrote: it was a sh1te wheelie, but it proves that he can get it up in 3rd and can do angles. In summery, mattsprattuk is a gobby little sh1tebag, dopehead tw4t, but sadly for all of us, he probably isn't THAT full of sh1te!!
Kickstart wrote: Hi I tend to agree with Matt. All the best Keith

[serlant]

Only other place I can see it coming from is the spark plug? pics lol

[MaybeGuy]

problem found now. it was a thin bit of carb slide that snapped off and worked its way into the cylinder and got pounded.

https://img192.imageshack.us/img192/5962/10062010216.jpg

luckily its made of very soft aluminium, and the head and piston all seem pretty much OK

https://img153.imageshack.us/img153/9523/10062010215.jpg

https://img412.imageshack.us/img412/1492/10062010214.jpg

if you look at the pictures, all the metal did as it was pounded was to remove the layer of coke from the head and piston (which would have also dampened the impact, and given me a slight decoking).

https://img193.imageshack.us/img193/6476/10062010213.jpg

https://img441.imageshack.us/img441/324/10062010212.jpg

also found out my ring gaps are slightly out, so a new set of rings and a carb slide and its going back together.

to be honest, i couldnt have asked for it to be much better considering what happened.
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Blue_SV650S wrote: it was a sh1te wheelie, but it proves that he can get it up in 3rd and can do angles. In summery, mattsprattuk is a gobby little sh1tebag, dopehead tw4t, but sadly for all of us, he probably isn't THAT full of sh1te!!
Kickstart wrote: Hi I tend to agree with Matt. All the best Keith

[Ed Case]

Considering what's happened lucky isn't the word for it, great news.