'smokey 260

[Doug]

Hi, my zed is just going again from a change of carbs and a few other things, and is running a bit smokey.

It is running a slightly rich mixture, and its going through a bit of oil (not litres ). I was told that the valves could be a bit tight such that oil is being burned off the inside of the engine (<< i dont understand what that means?? )

Would appreciate a bit of advice.

Doug

[Doehring]

What oil do you use ? I learnd that the elder engines had bigger tolerances than todays engines. So today's thinner oils can easily creep into the combustion chamber and are burnt there whereelse the former thicker oils don't do that. Look at the original recommendations. Maybe that helps already.

What do you others think about that oil question ?

Rolf

[smg1404]

Is the smoke blue or black? when do you see it? Is it when you are accellerating hard, or when you shift?

Blue smoke would indicate burning oil. Black would be too much fuel (rich mixture). I have never heard of valve adjustment causing a smoking condition. If you suspect the valves, by all means adjust them soon. Misadjusted valves (too tight) can cause damage to your head and valves. This would eliminate any question about the valves. If you are making blue smoke durring shifts, the problem is most likely valve seals, and maybe guides. If you see blue smoke all of the time, the problem is probably worn oil rings. The other possibility could be over filled oil. Check the level.

Good lick.

[owenk]

smg1404 comment about over filling the crankcase with oil made me remember when I over filled my 620 pickup because the oil was so clean I though it was off the dipstick! Well it was real funny watching the tailgaters back off when I went around corners or accelerated hard . The cloud was quite large and by the reaction of some drivers it must of been spotting their windshields. I may have stumbled on a way to back of the tailgaters . . . . direct oil injection! I can see it now in a JC Whiteny catalog now! Maybe I can retire on the profits:cheeky: