Ignition advance?

Question

What are the effects of a faulty ignition advance unit on a single cylinder engine? Would it explain a lack of power that gets worse as revs increase and a rich condition (black smoke, etc), while idle is perfect? Would it stop the engine from reaching max revs under no load?

Mixture is fine, probably would be lean if it wasn't for other problems, but cant deal with that until this is fixed!

Ok, and spark is good, compression is good, valve guides seem to leak slightly, carb has been overhauled and so on, air filter new. Starts easy, idles great just lacks power and smokes (black) a lot if you rev up, wont rev out just sits at what i would guess is about 4000, it is an '86 suzuki DR600 (waits for abuse lol) - thanks!

Answer 1

black smoke means its not burning fuel
Is carb set up correctly? sounds like main jet fell out?
If its an older single cylinder bike the advancer may be mechanical and so seized up ( even with electronic ign)
Later models have different means of advancing ignition curve, generally low speed goes faulty but either circuit can fail

Answer 2

before you do anything else take a compression test on the bike, if that's OK, then you can get a Snap-On digital timing light with a digital advance and with that you can check the advance perfectly, but I would tend to think ur bike has low compression, either caused by worn valves or rings, or a carb problem.

Answer 3

Always give year, make, engine size and model # when asking questions. We need all of that info to give an informed answer.
Older bikes have mechanical advancers and are easy to check their opperation.
Lot's of bikes have timming advance marks that can be checked with a timming light.

Answer 4

Yes to all your statements. Perhaps more difficult to notice but you should have High fuel consumption as well.