Topic: 76 cb550 running rich

[xhevi]

Other then the fouled plugs that make the start a pain I think it runs decent for my riding. (I mostly ride local rarely get it up to 60mph.) With cleaned or new plugs starts right up. It pulls ok but it takes only one ride to get the plugs fouled.

It is quite possible you are the cause of the plugs being fouled. If you ride this motor in low RPMs, slowly, you are "lugging" the engine. It wants to be ridden well above 4,000RPMs.

General riding that fouls your plugs tells you nothing. You have no evidence of where (throttle position) the fouling occurs. Time to properly perform some plug chops. IDLE first. Then WOT. Then MIDRANGE. Only then will you have evidence to what adjustments are needed in your carbs.

All and all looking at around 150$ to 200$. Not that bad if it saves me all the trouble. But I also working on my 73 bmw R60/5 and that needs cylinders bored Pistons etc.

Maybe will just get the needles and emulsion tubes for now and see how it does.

Stop believing spending money on "possibilities" and start spending some time doing what's necessary. If you have adjusted the needle 2 positions, assemble the bike, fresh plugs, and ride it properly (correct REV range). And be certain you are operating the CHOKE correctly. You would not be the first to operate it in reverse.

Thanks for the tips👍

[xhevi]

thought i would post an update.

Kept all the old innards and installed the carbs after a thorough cleaning and blowing compressed air through any passage. One of pins that hold the floats was beat up and binding, stopping the float for shutting off the gas, so i replaced all 4.  I had seen a post in here calling those pins to be 2mm brass rod, my carbs needed a 2.5mm rod, still a tiny bit loose but the geometry of the carb bowl will not allow it to drop. I also checked the gas level with the clear tube method, same gas level on all 4 and slightly below the bowl gasket.

The only change i did was raise the needle clip to the second position from the top (all 4 of course). After the first ride (about an hour at 4000 - 5000 rpm average) 3 sparks plugs were looking clean but #1 spark was fouled. I sorta understood why as i had not synced yet and i dissembled that carb more then the other 3. The air mixture screw was 1 3/4 turns out from lightly seated

Afterwards i vacuum synced the carbs and took the same ride (about an hour at 4000 - 5000 rpm average).  Now plug 1 and 3 are fouled and 2 and 4 are looking good. This is a carburetor issue, not a spark, 1 and 4 are on the same coil and 2 and 3 are on the other coil. There is good and fouled spark plugs on each coil. I will sync again.

NOW...... say 1/2 hour into the ride it heats up and runs like s#$%; i cant find the neutral at stop lights, has false neutrals between gears. Also when hot feels like engine breaking is very pronounced if i relax on the throttle. BTW i changed the oil from Rotella T4 Diesel to Golden Spectro 4.

The shifting issue appeared after the oil change, it shifted fine before.

The engine drag has always been there, even with the old oil.