Hello, few days ago I changed oil 10 w 40 out, 5 w 30 in. Miracle happened. With that lighter oil which is better for winter cold start I didnt noticed smoky start at all, even the bike was on side stand all the time.
Anybody with similar experience?

I use 20-50w mineral oil (dinosaur pee!); LFB doesn't always smoke when left on the sidestand and sometimes smokes when left on the mainstand!

I have always used Mobil 1 15W50 and always had smoke when stored on the sidestand. I never tried a lighter weight oil nor a dino based product.

Is the oil you used dino or synth?

Whether purging the motor with cheap diesel detergent mineral oil on occasion or springing for full bore fully synthetic in my Bricks, I've not had an issue with smoking upon start up. Then again, most of these bikes are old enough to smoke.

Seriously, the only K I've ever owned that regularly took care of the local mozzie population was my '87 K75.

nino wrote:Hello, few days ago I changed oil 10 w 40 out, 5 w 30 in. Miracle happened. With that lighter oil which is better for winter cold start I didnt noticed smoky start at all, even the bike was on side stand all the time.
Anybody with similar experience?

wow !!!  good to hear nino

5W30 is really too fluid for your engine.  Expect quick wear because of too low oil pressure and a film oil that won't stick to the parts. This kind of oil is designed to be used with a specific lubrication system with a pump that gives much more pressure, and oil lines diameter that are reduced to keep that pressure.
There's no need to use such a low grade, as a 10w40 can cope from -20°C. Do you really expect to ride under these temperatures or even start your bike?

For your non smoke problems on the side stand, the piston segments were modified in february 1988 to convert the oil segment to a labyrinthic version. Yet, as segments are turning around the piston when the engine runs, it may happen that all the extremities of the segments are in line, facing backwards when you stop it. Then it allows oil to pass in the combustion chambers, and the more the segments are worn, the more oil can pass.

I had minor weeps from my RS but after putting 20w50 mineral in it, it appears to have stopped. Same with the box and bevel, using mineral 80w90 GL5. Previous owner had been using synthetics.
Yes it smokes a little after sitting on the side stand but better that than a leak with thin synthetics.
My 83 K100 really smokes after side stand use, same 20w50 again but it clears after a mile or so. Both engines use no oil.
I am going to try them on Shell AX7 15w50 semi as I use it in the GS and Dakar and it’s cheap.