HELP Hard to start, I've tried everything!!

[dean350b]

Okay, rebuilt the top-end of the 1987 KX500C-1:

New piston & rings, clearances perfect, LOTS of compression.

New KIPS valves timed correctly.

Everything spotless, carb, airbox, pipe, you name it, its been cleaned and assembled correctly.

Cleaned the UNI air filter and lightly oiled it with 30wt engine oil.

New spark plug, correct one. Gapped at .025

Ohm Tested coil = good

Ohm Tested CDI = good

Ohm Tested Stator windings = good

Removed flywheel = perfect /keyway aligned/not slipping.

Removed stator plate, cleaned everything for perfect ground.

Keihin PWK with 168 main / 55 pilot / Screw out 1-1/2 / 2nd clip on needle. (tried many settings)

Idle screw set to many different settings, makes no difference.

Brand new Boysen SuperStock reed valves. New gaskets.

Float height set to 16mm.

Fresh 92 gas at 36:1 Castrol A747

Will only start if I pull the bike with a rope and a truck, engage he clutch in 5th gear she will fire in approx. 1/8 mile of pulling. She will then run, but really boggy & poorly. Feels like it is missing, etc.

Runs crappy. Cannot adjust anything on the carb to make it idle, but I guess you can say it does run???If I rev the engine, it does rev well, but will not idle at all, and tries to die if not always holding the trottle open somewhat.

Is not "crisp" at all.

Biggest problem is: Stop bike, try to start with kickstarter: All I get is massive (LOUD!!) backfires out the tailpipe every 10 or 15 kicks, but will not run.

Tried every starting technique on this website and some of my own, lay bike over, flood it, fuel pouring out tubes, etc. Nothing.

Any advice???

[KX5Zuki]

Hows your timing? Since you took the stator plate off, you might have put it back on in the wrong timing marks for a fairly stock motor. Even mine, since I coulnt kick it for the life of me, started up fine with a pull of only about 5 feet. Just a few rotations of the motor. Check your timing first. Leak test it as well.

[dean350b]

Timing is lined up exactly on the center timing mark like the factory manual shows.

Does the leak test verify the crankshaft lip seals are not passing compression into the gearbox?

[KXcam22]

That sounds like a timing issue. It is likely that your CDI box is crapping out.  You get good spark but the CDI timing is too far off to start.  Ohm test verifies that the CDI is not blown but doesn't indicate if it's working correctly (ie spark delayed in time). I would put a timing light on it to verify the spark is happening at the correct time (once you get it started). I have run into similar before and the only real clue I got was when the CDI finally died. Hope this helps. Cam.

[Hillclimb#42]

New Crank seals? Bike smokes a bunch and doesn't smell like a day at the races? Its a gamble when you don't go through the bottom, too.

[dean350b]

Yeah, I am leaning towards the CDI myself.

I got a random-mail from a Ebay guy I got a "bad" CDI unit from (would not Ohms test), and he stated he does not believe in Ohms testing the box, and said that CDI units either work (on a known good running bike) or do not work, period.

I have to kind of agree with him.

My transmission oil is brand new Dextron VI (ATF), and it is as clean as a whistle, even after running so poorly. Maybe I lucked out on crankshaft seals?

Anyway, after seaching a gazillion sites for a CDI box for a 1987 bike, a kind person on Ebay...again, sent me to this link:

http://www.electrexworld.co.uk/cd3502-cdi-unit-kawasaki-kx500-86-89-electrical-parts-for-motorcycles-electrex-world-2616-0.html

I hate to spend $160.00 (w/ shipping)!!!!!!

Do you guys think it will fix it?

Also for future search guys, here is a good link for the stator:

http://www.rmstator.com/en/dirtbikes/kawasaki/kx_500/stator/stator_for__kx_500/5374.htm

I could not find the Kawasaki (Hitachi) 21119-1221 CDI igniter box new anywhere.

[Hillclimb#42]

My transmission oil is brand new Dextron VI (ATF), and it is as clean as a whistle, even after running so poorly. Maybe I lucked out on crankshaft seals?

It would just suck oil into cylinder, thereby smoking, running way rich condition. It would not make the oil look dirty. Its hard to get lucky with the bottom end on older bikes.

Test with another "loaner" CDI first before buying. Or I wonder if a bike that had blown crank seals would run ok without oil in there. I just know, on our 86 kdx, a buddy of mine's 84kx125, and a few guys on here with pre-90 bikes, its the seals that are the worst on performance. Fix those and the carb adjustments will have an affect. All of the suggestions of tuning and starting techniques are based on the presumption that the bike has fresh seals and good compression. Basically that all the parts are within service limits. Most people ride it till it breaks, including me too many times.
What was it that Stewart recommended? Seals every two or was it three years? I don't remember the thread it was in, but, it sounded like there was some wisdom to his rebuild cycles.

[dean350b]

I'm a complete retard. I bought an FMF turbine-core silencer "barely used" on Ebay.

Barely used....yeah.

The entire "turbine core" spark arrester was plugged, completely shut by carbon.

I spent 2 hours cleaning and re-packing the silencer.

Bike runs awesome now!!!!!

Thank you to everyone for the help.

[KXcam22]

Good find!!  I never thought of that one even though I know that my bike will not even fire with the silencer plug in it.  Glad to hear that all is well. Cam.