Left-side Exhaust Smoking

[akpasta]

Recently bought a rebuilt CB77, and I notice with 700 miles on the rebuild, it's smoking a little from the left-side exhaust. Not a lot, mostly when rpms are above 7-8k. Engine breather tube smokes a bit too after the bike warms up.

One other irregularity is you have to have the left-side idle screw turned in about one full turn more than the right to get both carbs synced up rpm-wise, although I suppose that could be caused by the slides being slightly out of sync.

Is this something to worry about or are slight irregularities like this normal on these old bikes? I've heard that if you have a little smoking, thicker oil can help. Should I try 10w50? Haven't even changed the oil on her yet. These bikes all call for non-synthetic right?

I understand you gotta re-set the timing sooner when you have new points. I did that over the weekend with feeler gauges and a strobe, taking care that full-advance was timed properly. Everything seems to be up to spec and running well. Of course it can be hard to get points timed absolutely perfect and in sync; could timing cause a little smoking?

[LOUD MOUSE]

Ya may want to check the valve adjustment on that side and set your points following the FAQ "how to adjust". ........lm

Recently bought a rebuilt CB77, and I notice with 700 miles on the rebuild, it's smoking a little from the left-side exhaust. Not a lot, mostly when rpms are above 7-8k. Engine breather tube smokes a bit too after the bike warms up.

One other irregularity is you have to have the left-side idle screw turned in about one full turn more than the right to get both carbs synced up rpm-wise, although I suppose that could be caused by the slides being slightly out of sync.

Is this something to worry about or are slight irregularities like this normal on these old bikes? I've heard that if you have a little smoking, thicker oil can help. Should I try 10w50? Haven't even changed the oil on her yet. These bikes all call for non-synthetic right?

I understand you gotta re-set the timing sooner when you have new points. I did that over the weekend with feeler gauges and a strobe, taking care that full-advance was timed properly. Everything seems to be up to spec and running well. Of course it can be hard to get points timed absolutely perfect and in sync; could timing cause a little smoking?

[mike in idaho]

It's really important that both slides lift at the same time when you open the throttle. Back both throttle stop screws out several turns, so the slides are bottomed out in the carb body, and listen while working the throttle so see if they both click at the same time when they drop down. Back in my Honda shop days, I used to pull the float bowls off and unscrew the main jet holders. That would allow the tips of the needles to just stick below the carb body casting, you could place two fingertips against them and feel for movement as you worked the throttle with your other hand. With the cables adjusted properly the idle speed screws can be run back in and the idle adjustments made. Adjust the air screws 1/4 turn at a time for the smoothest idle, richen them as necessary until the off-idle throttle response is good with no bogging or spitting back.