chasing a miss

[quasi2008]

last week after a short ride of about 20 miles or so the bike started missing (bogging down) stumbling when rolling on the throttle. found #4 plug gas fouled. reworked the plug wire into the coil and boot and it began firing on all 4. still missing though. pulled vac hose off of #3 and activated the advance and the engine rpm increased a little at idle. checked the coils, good white/blue spark on all 4 plugs. terminals on coils have all been cleaned. this happened all of a sudden to. the next day I hit the interstate and run it up to 70/85 mph thinking maybe I had some dirt and it might clear it out. did the Wreathes Across America escort and hit the interstate to come home. was still running like a fat cow! I went thru the bike from one end to the other since I got it in October, including rebuilding the carbs. i'm actually suspecting the float levels, especially on #2. I started it up this evening without the air filter assy and had it choked for a bit and fuel rushed into the plenum from #2 it looked like. I might've choked it to death to! bike was running great until last week. however it was running pretty rich, still is. pulling the carbs tomorrow.

[ekvh]

You might be able to narrow your focus on the carb's leaks by conducting an observation of where it’s leaking. With everything dry, put a piece of paper towel cut to fit flatly in the plenum floor and turn on the fuel to see where it gets wet first. Along the plenum seams or from a particular carb can be seen in a few minutes. A full tank of fuel or some pressure to the feed will help.

If it’s a plenum leak, you know what’s needed. If it’s a carb leak, you need to dry it off, remove the slide caps and watch down the slide hole. Using a flashlight you will be able to see if it’s a bad float valve (or saturated float) if fuel comes up through the jets. If it comes from the plenum side of the venturi it’s your seal(s) on the carb-to-plenum.

I do it on the bike, but it can be done on the bench with an auxiliary fuel source.

The better carb builders all do this before reinstalling on the bike.

[quasi2008]

hey thanks for the info. was just getting ready to remove the carbs when this notification hit my email. i'll check things out. I checked the voltage at the coils this morning and they are both at 12 to 12.5 depending on rpm. I know one thing for sure, this engine is running so rich it should be FDIC insured!.

[quasi2008]

I think I may have found my miss. broken vacuum slide metering rod fell apart. i'd post a pic but haven't figured that out as of yet. anywho, the little round flange at the top of the rod came off, the rod was inop to say the least. had to use needlenose to pull it out of the jet. can't seem to locate any replacements either without buying a kit. threw the old ones away. saved everything else, but for some reason i didn't keep them.

[quasi2008]

IMG_0387.JPG

good quality parts!

found a set of replacements. going to change all 4.

[quasi2008]

slide needles came today. they are installed and the carbs back on the engine ready to check the balance and set the mixtures. thanks for the assistance. Happy New Year to all.