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Hello All,

I'm new to the forum, but I've read lots of posts, stickies and how tos. Looking for advice & support. I acquired a BW200 which pulls good but smoked badly. So bad I wouldn't want to be riding behind it. Here is what I've done so far-

Started with a compression test. Returned 152 psi at sea level.

Plug black an sooty.

Pulled head and both valves and chamber were covered in dry carbon.

O ring in block at head bolt intact.

Disassembled head, both cam and collar were chewed up where they mate. Evidence of rocker arm overheating. Valve stems looked okay.

Cleaned valves and checked for true. Both fine. Got replacement cam, collar and rockers from my parts bike.

Lapped valves, checked seats with dye and measured. All fine. Reassembled valves with springs and new factory valve stem seals. coated valves and chamber with light dusting of talcum powder. Poured in some alcohol. Bone dry

Very carefully cleaned the head mating surface of old gasket material with q-tips and acetone, then lightly lapped head with 1000 grit paper on precision granite stone just to verify true by removing dye. Head surface still had its factory machining marks.

Looked at bore and cleaned top of piston and it looked fine.

Reassembled head with new o ring, factory head gasket. Torqued bolts to spec in 3 stages

Rebuilt carb. No airbox attached for right now.

Did a compression test and returned 148 psi.

Couple of kicks, it started right up. Sounds nice and smooth, no valve train noise. Checked for oil at valley screw, all good.

White smoke still there at idle and at revs.

I'm figuring it's got to be rings? Or did I miss something simple?

Thoughts?
 

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With 152psi I doubt it will be rings - we have a few members here familiar with this particular bike, hopefully they be along soon to help ......

Welcome to the board ;)
 

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Discussion Starter #3
With 152psi I doubt it will be rings - we have a few members here familiar with this particular bike, hopefully they be along soon to help ......

Welcome to the board ;)
Thanks Purple!

Forgot to add that I checked crankcase breather and it flows fine.
 

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Pulled head and both valves and chamber were covered in dry carbon

Are you sure it not just running super rich? Does it actually use oil? Usually burning oil is blue.
 

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Discussion Starter #9
I'm wondering if gas has leaked into the oil. Maybe thinning it out enough to get by the rings? I'm draining the crankcase overnight and will try new oil tomorrow.
 

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Did you empty and refill the gas tank? Could be a heavy dose of Sea Foam or fuel stabilizer from the previous owner.
 
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