Bogging out and dying

[Rusty]

Hi there I'm back. My old thread petered out. Welp, here's the deal in case you didn't read the other. My bike was running very poorly a month after new points and condenser. Popping backfiring, etc. Found out the points just burnt up. Replaced them, but nicked my secondary coil . Sooo, new stator, new points, condenser, clean carbs, set float height, new filter heck even a chain and tires made their way on. Went on a ride and after just oh five ten minutes up to the old tricks. Runs fine then just bogs out and dies. It will fire back up and go again, then bog and quit. Made it all the way back home, just restarting over and over. I'm at a bit of a loss, hoping you all can help me trouble shoot my way out of this. Thanks

[racerclam]

If its not blubbering but just going blah and restarting with out a big cloud of smoke sounds like a fuel delivery problem sucking the float bowl dry then recovering. Pull the petcocks out and check the screens , the could be coveres with junk . If so rip the screens off and run a in line fuel filter . ????
Rich

[bchappy]

Also could be clogged up exhaust. I had that recently with a restore I was doing. I checked everything I could think of. Changed jetting and needle up and down and even changed to a working carb from another bike, installed new points and condenser, checked compression, checked leak down and changed coil to a working coil. Was about ready to pull engine to see if I had installed something wrong when I decided to change exhaust system and it ran fine. So now I have to try to burn out a muffler which I have never done.

[BrianZ]

Check to make sure the gas cap vent is not plugged (the vent is a tiny hole in the gas cap). If the vent is blocked a vacuum will be created in the fuel tank after a few minutes of running. This will starve the engine of fuel. When the problem occurrs try loosening the cap and see if air is drawn in to the tank. If so, you have a blocked vent.

Brian

[rlkarren]

yeap, I would agree. You're emptying the float bowl faster than it can fill.

Check for clogged fuel lines/Petcocks/Cap vent/Float valve. Then check your exhaust. I use a propane torch to clean out my exhaust. Set the torch to blow inside either end until everything burns off. I don't let it get bright red hot, just to the point it starts to turn red, then remove heat. You'll want to re-paint it when finished though. Works for chrome pipes but you can't get it as hot. It will discolor chrome.

[Rusty]

Thanks all. I will check the petcocks. I Blew threw the gas cap the other day to see if it was clogged. I'm actually getting gas leaking if I leave the petcock on though? I did the ole chain thing with the exhaust a little while ago. It seems to blow pretty well when I hold my hand over it. I can see how it could be fuel starvation it does kind if act like that. I'll report back when I get a chance. Thanks

[Rusty]

"restarting with out a big cloud of smoke" what would it mean if it did smoke?

[bchappy]

Rusty, I don't know the answer to your last question, but you can tell if it is an exhaust problem by taking it off and running it. It will be loud with the pipe off and your neighbors may yell at you, but if it is clogged it will run fairly clear with the pipe off. Mine seemed to be blowing ok as it was smoking but apparently it was clogged enough to cause it to bog down badly at mid range and top end. This don't take long and it will eliminate one possible problem.

Roger (rlkarren), an a acetylene torch did the trick on my pipe. It now runs like a scared rabbit.

[Rusty]

Will look into cleaning the exhaust properly and the pet cocks, and other possible fuel flow problems. So what about gas dumping out of bowl. usually thats stuck float, float height or plugged main jet, right?? thanks all!!!

[Dale]

The most likely culpret would be the float valve and seat under the float arm. It might just need a good cleaning or it might have a groove worn in it and need to be replaced. Pretty common issue and I believe was covered in a Resonator Revisited article. Also, check the float arm adjustment. It should sit parallel with the gasket seat when you hold the carb upside down with the float bowl removed.
Dale