Alright, this is going to be a long one,and I'm sorry.
First off:
1975 CB550K (Just reassembled engine 230 miles ago)
Uni replacement filter (in unmodified factory airbox with factory intake system, other than the vent hose isn't hooked up)
Old Jardine 4-2 slip-ons (been on since before I had the bike)
1980 CB650C camshaft (definitely the one with higher lift and longer duration, installed with recent rebuild)
New rings and hone job (with ball hone), .016 endgap, was careful to read and re-read the manual and the forum about ring direction and markings
New NGK D7EA's (slid smallest and largest feeler gauges for gap specs in: they are gapped somewhere in the middle out of the box)
Newer NGK plug wire caps (10k ohm)
Points set to .016 inch and cleaned (worked great before the rebuild)
Carbs (stamped 022a) worked last summer, drained the fuel, dropped the bowl, sprayed the jets through with carb cleaner)
Moved the needle up one slot (to 5th from the top)
The floats were set at a little over 24mm, I changed then to 22mm (it would idle down and back up after revving if you blipped the throttle at a stop light, figured that explained that)
Ran it in front of a fan for about 8 minutes the first time I started it and drained the oil.
Ran it through four 15 minute rides with slight increases in amount of throttle applied and RPM's turned as people described and linked to on this sight, but a little more conservatively, then started riding it easy. Rarely more than 1/4 throttle, almost never more than half throttle, never near full throttle, usually below 5 grand, only only passed 6 grand twice (just got carried away)
The bike has been running rich. Super rich and fouling plugs with black soot. I tried tuning with the idle screws, no effect. Tried resetting the floats to 24 mm and double checking how I was measuring, very little change. Put the needle back to stock position (#4 from top), resetting idle screws to 1 turn out, resetting floats to 22 mm and new plugs, no change. Currently the idle screws are turned out only 5/8 of a turn (so they are leaner than the manual suggests by a quarter turn) and th plugs are still sooty.
I have checked spark, it looks great after I clean the plugs. I have the timing plate at full advance, but have never heard anything like pinging.
When the bike was at it's worst (22mm floats and 5th clip position,, plugs not cleaned for 100 miles), it fouls the plugs out all the way, with gratuitous backfiring.
While limping it home, it got louder. This was before clip change and new plugs. I figured I might have damaged the baffles or I hadn't tightened the header nuts enough. I tried tuning it for a while with no luck. Turns out the header pipes leak where the meet the slip-ons and I blew out the baffle for 3 and 4.
So, I'm waiting to figure out an exhaust before I tune anymore. My question is:
What do I do next?!
Could the longer duration cam and greatly reduced back pressure be giving me inefficient burn, thus leaving the plugs sooty without it being all that rich?
Do I drop the floats (increase the mm's again)?
Is it possible I somehow got ever ring on every cylinder upside down despite being super meticulous in my build?
Did I manage to install my new valve seals incorrectly on each cylinder?
Wouldn't the plugs feel oily/ be shiny/ feel sticky instead of having dry, powdery carbon on them if oil was the problem?
What the hell should I do?! I just want to ride!
Sorry this is so long, I m just at a loss as to what my problem is and wanted to include every potentially useful piece of information. Let me know if I have forgotten anything.
Actually, I tried using a timing light to check my timing, apparently I got a broken one brand new and harbor freight 4 months ago and lost the receipt for it. I don't plan on buying anoth because I am now flat broke after this build.
Thank you all. I don't have much in the way of a working bike, but I wouldn't have gotten this far without this forum.
