So i went to go ride this evening and the bike wont start.

I pulled the plug and it was dry.  It had some carbon deposit on it, but it was dry.  I cleaned it off a bit and started the bike with the plug pulled and almost touching the motor.  The spark jumped about an inch!  So the plug and spark is good.

I smelled gas, but not too much.  The bike did sit for a little bit, but i just rode it last week and it worked fine.  I suppose i could clean the carb but i'm thinking it's fine.

the only other issue is, the area where the exhaust is, there is some black soot.  I must have an exhaust leak.  but i havent washed the bike in months, so the black soot seemed normal for a slow leak.

So...

I have spark
I have gas
what else do i need to make the bike work?


I was thinking of pulling the head off and re-doing the seals.  but i dont think that's necessary.

any help or ideas would be great?

thanks all!

I actually took the cone filter off when tryinh to start it and no luck. Any other ideas?

Oil was at lower level but ok, i added some.

I cranked it and tapped bowl with no luck.

Bike has about 20,000 miles on it

I may just pull the carb and clean again

take the carb off... clean it... and make sure you check the fuel screen. I had mine gumm up and it took me forever to figure out what it was.

But does it seem like you really don't know why it wouldn't start ?

A dirty carb is seldom if ever a reason for not starting,.....unless it is flooding.

Remember that a spark plug that fires while setting on top of the engine, may not fire while under compression. And that can be caused by 2 reasons,......
one is that the plug is dirty/defective.
The other can be lack of battery voltage to get good ignition fire.

From my experience,....and from info here from the super techs,  I have determined this bike needs good battery voltage to start easily.
Just because it cranks over, doesn't mean its getting good enough spark to fire the plug.
So, my advice would be....anytime these bikes won't start for no apparent reason, go for the battery charger first !

When I pulled my 86 out last year I drained the tank and the float bowl and put in fresh gas.  Cranked it and it fired right off, ran for about 5 seconds and died.  Checked the plug like you did, cleaned it and tried again, no go.  Pulled the carburetor, soaked and cleaned it and tried again and even jumped it off a car and nothing.  Couldn't be the plug I thought but I bought one and installed it anyway.  Fired right off and has started perfectly ever since.  Who would have thunk it?  

My ex father-in-law was a mechanic in the old days, 40's 50's & 60's, and a pretty good one too, I suspect. His advice was, "about 90 percent of carburetor problems are in the ignition."   Ignition problems aren't as prevelent as they were back then but still some good advice I think.

Now if I could just get rid of this darn stuttering at less than a quarter throttle I'd be happy.