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RM125 with following symptoms, help!

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I am trying to diagnose some issues I am having with my 1999 Suzuki RM125.  Symptoms include:

  1. Low power, the bottom end seems OK, but there is no real increase at all.  The engine revs up, but the bike doesn't really accelerate with a punch like my 1997 CR125R (not bogging though).
  2. Smoke seems a lot thicker than my CR.
  3. There is a pinging sound from the exhaust, I've heard that might be an air leak caused by a bad magneto-side crank seal.
  4. Sometimes when riding the bike will rev up on its own.
  5. Black spooge sometimes comes out of the tailpipe.

Some more info on the bike:  I checked the float level and its good.  Has a pro-circuit fatty and the jetting specs matches the pro-circuit website.  The bike has a new top end. Running 32:1.  Coolant level doesn't drop (so no leaks there).  Crank was rebuilt too.

Here's what I think:

  1. Top end needs more time to break in.
  2. Crank seals need to be replaced.
  3. Power valve spring knob needs to be adjusted (don't know which way to turn it, there is a clockwise arrow on the knob but not sure it that will increase or decrease).
  4. Maybe I should run a hotter or colder spark plug?

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1 hour ago, kevelev said:

Yeah, I know I shouldve just replaced them then...

Did you replace crank bearings? ?? You put new crank in without new bearings and seals?  Crank bearings were probably the problem to start with. If a crank seal is leaking its cause there's slip in bearing normally or it's old and wore out. Crank, crank bearings and seals are the heart of your engine.  

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And that is why it is sucking oil out of the transmission and blowing it all over your rear fender and swingarm.

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