Second post: Starting.
When I first got my bike, it seemed hard to start and reluctant to idle, tending to stall. It seemed to be very fussy about ignition issues. It also seemed reluctant to pull below 3500RPM, and lacked torque.
At first, I focused on the ignition. It was not enough. However, the ignition is not as strong as one might hope, and all of our bikes are old. For those reasons, I recommend y'all do the following things anyway, it is guaranteed to make your bike more reliable, and clarify what problems remain.
-Clean and polish every connection in the core electrical system with a Dremel buffing wheel and rouge, wiping the rouge off with a rag when you are done. You want all the following connections mirror-shiny, tight, and greased with dielectric grease. If a dremel won't fit, a small pocket knife is also good for scraping contacts. If you use emery paper, clean the connection carefully afterward so the grit doesn't stick around and compromise the connection.
-Fuse clips and fuse contacts
-Main key switch
Fuse note: The bronze OE clips are likely to shatter in your hands. Radio Shack p/n 270-742 fuse blocks have clips that, with a little persuasion, can slide right in, replacing the OE garbage. These new clips are strrrong like Boool. They are subject to corrosion, though, so grease them. You can solder them to the wires or crimp them. Crimping is better, but spring for Ideal ratcheting crimpers, and insist on terminals that fit snugly over the wires you have. Compromise on either of these points and the connection will corrode or pull out.
Switch note: Old japanese switch gear is awesome. You can take it apart and clean it easily. Keep your hand cupped around it while removing any e-clips, and work on a clean table or cookie tray to capture stray bits. Just pull it apart slowly so you see where the springs, balls, and contacts go before they fall out. Basically, if you see a spring, it goes against a ball, or a moving contact. The other contacts are on a backplate of some kind. Polish the backplate till it is all shiny. Polish the moving contact, just so the parts that touch the backplate are shiny. Grease the backplate and any moving parts with dielectric grease, and put it back together.
Check spark plug boots for about 5K Ohms resistance. They unscrew from the hot wire. Replace if they are cracked or fail the test.
Replace plugs if over 8000 miles old.
Doing all this work is guaranteed to pay off in reliability. In extreme cases, it can double the voltage available to your ignition system, brighten your headlights, improve your battery life, and make it start when it wouldn't.
After 30,000 miles of babying the ignition system, which helped a bit, I finally stumbled on the missing link. Two things.
Clean the idle mix adjuster screws with carb cleaner, right on the bike. You do this by counting exactly how many turns you need to screw them in before they seat, writing it down, and then removing them, spraying lots of carb cleaner in, and replacing the screws. You seat them gently, then back them out by the right amount for each side.
Remove the throttle piston/diaphragm assemblies from the tops of the carbs, once again doable right on the bike. Look at the sky through the diaphragms, scrutinizing them for holes. Holes are most likely in places where the diaphragm folds. Since the diaphragm is reinforced with something like cotton fabric, Blue RTV silicone will stick to the cotton. If you work a little dab of RTV into small holes, it often seals them. My fix worked for 30,000 miles.
After this, my bike started easily, often without enrichener in the summer, idled like a clock, pulled cleanly down to 2500RPM, and had much more power down low.
Swingarm pivot takes on water. Needs to be taken apart and lubricated. Lubricate the PIVOT and Bushing, don't stop at the axle that holds it on the bike. This can be done with the rear wheel and brakes installed, and the chain loose, by removing the pivot axle and tapping the pivot side of swingarm downward till it clears the bike on the bottom side. You then tap out the pivot, clean it all, then put the pivot back into the bushing.
Brakes are often weak and hard to control. See my review for the solution, which works a treat. A notchy, coarse feel at the lever needs a master cylinder rebuild. Not too hard. Lubricating any pivot points with automotive grease is good.
Shifting first to second sometimes doesn't engage, and falls into neutral, or makes shifting into third actually complete the shift into second. You learn to get the feel of it and shift twice sometimes.
Unit sometimes drops out of fifth into a false neutral. If you are accelerating when this happens, you can overrev. This burns the rings, causing oil smoke. For this reason, next time I need to work on the rings and cylinders, I am going to find or make a rev limiter.
Clutch mechanism is complicated, and should be completely lubricated at valve adjustment time, to perform.
You probably need lighter fork oil. I weigh 230, and settled on 15W. This improves cornering. So does changing it like they tell you.
Spring for a modern o or x-ring chain, when your current one goes. Replace sprockets with it. They are sooo much more precise and last like you wouldn't believe. I only have to check my chain tension every oil change.
Take the oil change interval seriously. Castrol 10W40 is good enough for 90,000 miles, but you feel coarser shifting as the oil wears out, so 2000 miles per change. Really.
Continental TKC12 vintage sport tires are awesome. Super sticky, but they only last 8000 miles in back.
If your bike wobbles on bumpy roads or in wind, it might be loose headset bearings, but it might be your own fault. The steering inputs are very sensitive, and when you start to get into serious maneuvering, you need to take care to support your own weight, and isolate your body movements from your handlebar inputs. Elbows up, arms bent, legs hugging tank. Then you can wring it out and really dance. If you sit back, straight armed, and try to turn, it will feel very insecure.
I hope this fills you in on the major stuff.