I'm Stumped. Bad Backfire.

[YellowJacket!]

OK, the bike was running great the other day.  Just replaced the battery and fixed my R/R wires which melted at the plug.
I have tried unsuccessfully for the last two days to get the bike started.  The battery is fully charged.
Lucky suggested that I drain the fuel and the bowls which I did.  New fuel and still the same.  I know I'm getting fuel to the bowls because I drained them again after I refilled the tank and primed them.  Fuel filter is clear and fuel line is not kinked.
I can see the accelerator jets when I pull the throttle and I am seeing a straight stream of gas firing straight down the throat of the carbs.  Not a fanned out stream but a straight, steady squirt.
When I'm cranking, the engine does not even catch but I am getting a very loud bang out my MAC exhaust, as well as sometimes a delayed, one second after I stop cranking, backfire.
I have a second, good working TCI which I swapped out but that did not change anything.
I also checked bth plug wires and they seem ok but I have not checked for spark yet as the bike is out in the sun and its too bright.  I'll have to move it to the shade. (I'm really missing a great riding day.  :'(  )

David

[YellowJacket!]

AAAHHHHHAAAA!! Figured it out.  I pulled the plugs to check the spark and guess what.  Filthy dirty nasty carbon encrusted plugs.  Probably forom a year of riding with my jets reversed.
Cleaned the plugs, and she cranked right up!  ;D  ;D  ;D

David

[Lucky]

doesn't take much does it, lol
lesson learned: no mater how unlikely it may seem, suspect it  ;D

glad you got it!
--Lucky

[h2olawyer]

Nice catch!  I would have been stumped a while with that one, too.  Nice demonstration of tracing electrical & fuel related possibilities.  Guess I'll put new plugs in this year.  Don't remember when I installed the last ones.

H₂O

[YellowJacket!]

It is absolutely unbelievable what a difference it made in cleaning the plugs!!  Even though they were new plugs, I guess driving around with mixed up jets and an out of sync carb last year took its toll on them.
Once I had the tank back on and the bowls primed, she started right up.  Even her idle and revving characteristics are better.  The exhaust even sounds different (I guess because I'm not blowing out unburned fuel).  Now that I have my jets right, the Macs on, my plugs clean and my YICS sealed (tight as a drum when I checked it today) and , thanks to H2O's link, my Uni filter on the way, this bike rocks!  ;D  ;D

David

[h2olawyer]

But will you keep up with Lucky now?   :D

H₂O

[Night Vision]

  I pulled the plugs to check the spark and guess what?.  Filthy dirty nasty carbon encrusted plugs.  Probably forom a year of riding with my jets reversed.
Cleaned the plugs, and she cranked right up!  ;D  ;D  ;D

for $4 with tax, I'd put 2 new plugs in....... iffen I had the old ones out  ;)

[YellowJacket!]

  I pulled the plugs to check the spark and guess what?.  Filthy dirty nasty carbon encrusted plugs.  Probably forom a year of riding with my jets reversed.
Cleaned the plugs, and she cranked right up!  ;D  ;D  ;D

for $4 with tax, I'd put 2 new plugs in....... iffen I had the old ones out  ;)

Thats on my plan.  Shoulda done it today while the tank was off, but I just wanted to get it started up, plus, I parked it behind my car and along with all my other tools scattered about, it just wasn't going to happen.
I did figure out something that made it easier to get the plugs in and out though.  I have a ratchet with a twist handle.  You can use it like a regualr ratchet, or, in tight spaces, you can twist the handle to loosen up or tighten down whatever you are working on.  With a 1" ext, it fits right between the cams and makes getting the plugs in and out way easier.

David

[Tiger]

:) Well done Dave... 8) For what it cost's, I change the spark plug's at the start of each riding season, also the engine oil, oil/air/gas filter's.

                        8).......TIGER....... 8)

[h2olawyer]

Get your hands on the OEM toolkit.  The spark plug wrench in it works great!!!  Other than the shock preload tool, the rest of the tools are junk.

I pulled the plugs on mine two years ago.  Looked nice & medium brown with no signs of wear.  Gap was still good.  Forgot about it last year.  Going to get plugs for both bikes this week anyway.

H₂O

[YellowJacket!]

Get your hands on the OEM toolkit.  The spark plug wrench in it works great!!!  Other than the shock preload tool, the rest of the tools are junk.

I pulled the plugs on mine two years ago.  Looked nice & medium brown with no signs of wear.  Gap was still good.  Forgot about it last year.  Going to get plugs for both bikes this week anyway.

H₂O

As Homer Simpson says;" Dooohhhhhhh!"
I have it and didn't even think of it. Doohhhh!

David