Burning smoke like an Apache

from where ?
valves ? in or ex
dipstick ? rings
Jiggered if I know - first leakdown test I've done tbh. It sounded very much like it was coming from the valves or the jug itself. Opening the throttle made no diference to tone, pitch or volume so I don't believe its the inlet valve. Whipping the oil filler cap off gave a louder sound and the rocker cover did appear to be pressurised a bit, but difficult to tell if the leak was coming from the valves, the guides or the jug. I'll have another go with some tubing

In the video the guy who sold me the bike did replace the valve stem seal with some new ones but in doing so, he removed the old ones with mole grips so I'm wondering if he inadvertantly ovaled one of the guides and whether this would cause a poor seal on the valve stems sufficient to allow a lot of oil past?
 
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you have to pin it down , if you do not , you will have to cover every base in the HOPE of fixing it.
otherwise you are wasting your time .
and you've done that already .
did you do LD properly ?
compressor full .
engine at TDC , valves shut .
lock engine stationary , either lock the crank or in to top gear and strap the rear brake down HARD . you do not want the crank turning.
connect LD to compressor , ZERO it , so it shows 0% leak
connect to engine . note % leak .
take tube , listen at exhaust port or rear of pipe .
listen at throttle body , or vacuum take-off point .
remove dipstick , listen .
a % of 0-10 wouldn't worry me , check it against the other side ? are they even to within 5% ?

if you still can't work this out , go and find Martin Vermiere , trading as martins mechanical services , he is in Crickhowell


 
you have to pin it down , if you do not , you will have to cover every base in the HOPE of fixing it.
otherwise you are wasting your time .
and you've done that already .
I had the time so I don't conssider it wasted to whip the head off and have a quick visual inspection to see if there was anything obvious given that it had been recently disturbed. It didn't take long but I take your point.
did you do LD properly ? CHECK
compressor full .CHECK
engine at TDC , valves shut .CHECK
lock engine stationary , either lock the crank or in to top gear and strap the rear brake down HARD . you do not want the crank turning. CHECK
connect LD to compressor , ZERO it , so it shows 0% leak CHECK
connect to engine . note % leak .See below
Did all that and leak LH side %was 25% @80psi
take tube , listen at exhaust port or rear of pipe .
Very faint hiss but way in the background background and obviously coming from elsewhere in the combustion chain.
listen at throttle body , or vacuum take-off point .
VTO point and again at air filter housing. Again very faint insignificant background hiss not indicative of being the source. Opening Throttle to WOT made no difference and according to other guides if it was inlet valves I would have expected the hiss to get noticeably louder. It didn't
remove dipstick , listen .
Noticeably louder hiss when oil filler cap is removed than any of the other points (I presume thats what you mean by the diptstick - oil level on the 1100GS is by sight glass).
a % of 0-10 wouldn't worry me ,
Results

R/H cylinder
Only very faint hiss only overall
No noitceable hiss from either pipe or VTO.
Comp test 192 psi which seems over-good
LD Test 22% @80psi - slow drop in pressure over time

LH Cylinder
Slightly louder hiss than RHS. Gets notably louder when oil filler cap in rocker cover is removed but still doesn't sound like it's coming from valve seals. Sounds like its coming from further inside.
VTO and Exhaust sound about the same as RHS
Comp test 162 psi which seems not so good comparatively
LD Test 25% @80psi - slow drop in pressure over time.

"check it against the other side ? are they even to within 5% ?"
LD seem to be within 2-3%, one side to the other. LH side leaks pressure @ slightly faster rate.
Compression test seems significantly different.

if you still can't work this out , go and find Martin Vermiere , trading as martins mechanical services , he is in Crickhowell

 
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a % of 0-10 wouldn't worry me , check it against the other side ? are they even to within 5% ?... yes !

you will not see it from the valve guide seals , unless you use a mityvac and seal the valve with silicon.

30 psi down says there is something happening .
squirt oil into the lhs , to get the rings wet , and redo a comp test , if you get a big leap , repeat on the rhs to compare .
 
No, not yet but I have just been mega busy with work and then my back went out so no rolling around in the muck and the bullets for me for a while. I'm still up to my nuts with work and now it's dark, cold and sh!tty outside so I'm disinclined to do anything with it until the spring. I still have another (decent) bike to use so there's no rush. The leak down and pressure tests seem inconclusive to me so when I have more time I'll have it apart. At which point it will either become obvious what the problem is, in which case it will get fixed or, it won't be obvious what the problem is in which case it will stay in pieces and get parted out probably.
 


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