summer wearing on....bike running worse

[oldrookie]

Update:

1. Checked all air connections. Found raw fuel in the throat of the left carb and in the air box. Cleaned everything and adjusted the clamps on the carbs.

2. Oiled the air filter.

3. Put new spark plug in the left side. Started fine, but within 3 minutes of idling it started missing. Pulled the plug. Dark and wet.

4. Adjusted the fuel mixture screw back down to snug and loosened it one revolution. Plug still got wet after a few minutes of sitting at idle with the occasional rev. Started missing again.

Seems that it is getting fuel and air, that only leaves spark. The former left coil is happy as a clam on the right side with no missing from that cylinder. The former right side coil is not happy on the left and is missing badly after a brief warm up. So the problem is not following the coils.

So, two big questions..

1. Is it getting too much fuel, or
2. Is it not getting enough spark?

Pretty sure, after turning down the fuel to one rev open that it is likely to be the spark.

So where in the chain of spark is the most likely culprit?

[oldrookie]

More confused than ever.

Went out to test the ignitor. Test worked last night, but can't get it to work today.

Can see both plugs sparking if the ignitor is plugged in and the plugs are grounded to the engine.

Put the plugs back in, started it up. Left side is not firing. Can hold the exhaust up near the cylinder head for as long as you want.

Looked back and saw fuel running out of the lower corner of the air box. Opened it up to find gas sitting in the rubber connection between the left carb and the air box.

Any ideas?

[Guest]

Your flooding.

Needle and seat are probably bad on one side or the other.

[Big Rich]

Agreed. If it's not the float needle/ seat, it could be the float sinking too. Let me know if there's any little parts you need...........

[oldrookie]

So, just because I want to make sure I understand...

Idles fine because the float is preventing fuel from flowing while not running, but once it starts up...float and needle are allowing too much flow for the bike to to use in combustion chamber. Result is a fouled plug--causing the misfiring-- and fuel filling the bowl and then the rest of the carb, backing up into the air box. That sound right?

Stuck in FL for few days, but will tear it down again on Monday afternoon.

Big Rich, thanks for the offer. Will pm if I find this is a parts issue.

[Guest]

I would agree with Mechanix and Big Rich on the flooding. And both of their deductions could be the culprit. But oldrookie...stuck in FL? I thought FL was a good place to be?..

[Big Rich]

You've got it right Rook. Try taking the left bowl off and gently press up on the float with your finger. Turn the petcock to prime for a couple seconds - if gas pours onto your finger then it is the needle / seat. If you take the float off and shake it and hear gas inside, that could do it to. Ever hear of using a clear fuel line attached to the drain screw to check float level?

[oldrookie]

"stuck in FL" might be good if my bike was here and I could work on this issue..mine is in Indy and it will be days before I
can get back to it. Supposed to get up to 6" of rain too.

Thanks for the test, Big Rich. Have seen the clear tube test...just haven't made one yet.

[oldrookie]

Okay, think I found the problem.

I tore the carbs off and got into the left carb. Everything looked normal and clean. Took all of the jets out and pulled the choke and the mixture screw out. Everything looked good.

Put it back together and something about how the float was operating didn't seem right. Pulled the float bowl off the right side to compare float operations. The right side was springy, the left side wasn't. The left side float just dropped straight down on the needle with a solid feel. The right side was bouncy.

Pulled the left float needle out and found that the center of the needle was stuck down. I worked it free and it appears to be working correctly now.

Probably need to replace it.

[rustybronco]

Pulled the left float needle out and found that the center of the needle was stuck down. I worked it free and it appears to be working correctly now.

Probably need to replace it.

Soak it in carb cleaner.

[oldrookie]

Will give it a try.

Thanks.

[oldrookie]

Got a starter in from Old_skool and installed it. Got a needle valve from Big Rich, holding in reserve since I'm betting the old one will stick again.

Started better than it ever did with the old starter--even after I rebuilt it. So, looks like I am back on the road until the next issue.