Blue Smoke

Hi
i've had my Berg fe501e 2002 for 6 months maintained it regular, oil changes after each thrash ,valve's checked ,its always sounded noisy but has had stacks of power for supermoto,and gave the KtM boys a good run for there money,and the plastic rockets a good kicking on the B roads until today,well its finally died the beast is breathing blue smoke and sounds like somethings trying to escape out of the engine with a hammer.
After putting it the van to get home(normal thrash it home ) i've pulled the top end off to find everything as it should be ,inlet and outlet rockers all in one peace,spark plug in good condition cam looks fine cam chains ok,took clutch casing off nothing looks out of place ,sump plug has no metal stuck to it ,so my conclusion is the piston/piston rings have gone,
Problem, do I have to drop out the engine and split it to replace the piston as i see no seam where the barrel sits ,i've never came across an engine where the barrel is part of the bottom end,the designer of this should be shot a simple job made hard work if anyone has any advise on what not to do im listening,
thanks

:evil: man with big hammer can fix anything :evil:

Update:
finaly got engine out after many hours trying to remove swinging arm bolt.both nuts unscrewed easily,but removing the rod its self was a nightmare,seized solid,tryed many different methods i finally took the whole lot to the local engineering shop who had to press it out using abnormal amounts of pressure,so now have to get a new swinging arm rod,
engines now in many parts and split very easily,I've filled my memory card on the camera taking shots for reference so thats all good.
problem found with the engine, the bottom ring has cracked and the main bearing has gone hence blue smoke and loud knocking,
Question for anyone: Does the 550 piston and sleave fit, of do I have to put in the standard 501 piston/sleave in ,also what other upgrades are worth doing while I have this engine stripped down,
thanks

:evil: man with big hammer could not fit it :evil:

final update

Hi
Well finally got around to fixing the beast after 2 weeks of waiting for parts to arrive.new piston and sleave,cam chain,new valves,rocker bearing (outlet cam )had the main bearing mod done,new clutch basket,and bearings,and a few other bits that need sorting out.found a peice of metal jamed in the gear box which was stopping 6th being select,so after a few hours of putting all the bits back together and looking at at the photo's i look,(taking photos of this sort of project was well worth the effort would recommend doing if possable)new oil,filters,cleaned the stator ,set the valves ,new carb, fitted,new plug, battey charged refilled the tank so it has fresh petrol ,nothing left in the box ,washers bolts or screw's every thing has a home which was good news,
finally the big monent arrived,will she start?
first kick 2nd kick 3rd kick ...250 kicks later,plug in plug out lots of swearing ,blood,snot and sweat dripping out of the old man,and a simple thing like turning the key on was the problem ,Oops
,hubby was not a happy chappy,turned the key and bingo the beast lives ,no rattles clunks or bangs ,sounds sweet as a nut,heres the biggest shock the E start is now working once the engines warmed up.Ive used the Berg all week ,2nd kick in the morning and off the button every other time.

Ive added a few pics to my gallery of damaged parts,

cheers all

Made mr chuckle