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G'day all! I'm still experiencing smoke issues with the 100RS and after checking bores (OK) and valve guides (OK), replacing the rings and ruling out any head gasket defects, I'm at a loss to explain the smokey idle and on acceleration!Piston skirts are unmarked, no evidence of blow by.I've even run the crankcase breather to the outside to eliminate crankcase vapour as a source of the oil. Observers following me on the road reckon their is no smoke whilst on the move but on strip down, the combustion chambers are full of powdery carbon, even after a couple of hundred miles.Everything points to guide wear but the valves don't rock at all in the guides!!? I've obtained a set of valve guide seals that will fit the BMW guides but before proceeding (a desperate measure?) I need to know; has anyone tried this before? Is it an acceptable practice, could I be doing any damage to valves, etc, cutting out a source of valve stem oiling? After 3 engine strips in the past month, I'm nearly over it!! Paranoia? Any suggestions gratefully accepted! hools.

Are you certain it is oil and not a over rich mixture - as a general rule oil is wet and fuel is dry and powdery.

Check the fuel levels in the bowls - Snowbums site has the information you need.

Bad luck to hear you're having troubles with that RS Hools, have you tried 98 octane instead of diesel?

Roy Gavin wrote:Are you certain it is oil and not a over rich mixture - as a general rule oil is wet and fuel is dry and powdery.

Check the fuel levels in the bowls - Snowbums site has the information you need.

+1. Oil burner heads are wet, black and have an oily odor. Over rich, dry and black on fresh heads. An over rich mixture will also cause you to use more oil. It washes the cylinder walls and you burn the oil that should be lubricating your rings.

Carbon from over rich will also wear guides rapidly.

Are you certain it is oil and not a over rich mixture - as a general rule oil is wet and fuel is dry and powdery.

Have you had someone ride behind you to check for smoke? If so, did you do the standard night test?

ME 109 wrote:Bad luck to hear you're having troubles with that RS Hools, have you tried 98 octane instead of diesel?

You're just an unkind man.

Thanks everyone.....even you Jeff, ya mongrel!! !You'd reckon you'd give a bloke credit for pre mixing the diesel and 98 before it went into the tank!!!
Forget the valve guide seals?!!
Given that the carbs in question are dellortos. I'll recheck the float levels. Would leaning the idle circuit down as much as possible be a start?

The (adjusted or mal-adjusted) float level of any carb affects fuel/air-mix delivery ...
I'd start the carbs check with a thorough cleaning, inspection, and proper tuning –
Leaning the idle will only solve the problem IF that will have been the problem.

Theoretical speculation or anecdotal experience
will be but a poor substitute for "hands-on" critical observation & analysis, eh ?