coughing

Thanks for the responses. I did not mention that I have replaced the right side coils in 05.
This morning I rode to work and the temp was in the low 30's and she coughed intermittently all the way (15miles), but coming home the temp was in the low 50's and she ran like a bat out of hell. So now I am really confused.
Mark

I checked the leads to the coils last weekend and I thought there was too much play so I tightened the connectors. I agree with everyone that it has to be the coils. Wednesday I rode to work, ran like ***** going ( at 34degrees) and ran great coming home in the 50's. I really thought I had a chaffed wire somewhere and was going to rip the bike apart until I found it. Now I am back to the coils.
Mark

I let her warm up long enough to have a smoke. The whole time decreasing the amount of choke. She coughs the entire time to work (15miles). I am going to throw a coil at here tomorrow.
Mark

I considered carb icing, but... This morning I was going to ride to work, but she was hard to start and ran very poorly from 1000-2000 rpm. After 2k ran fine. I took off my gear and drove my truck. I am going to recheck things tonight.
Mark

I borrowed a lazer thermometer from work and shot my exhaust pipes by the radiator. My #3 cylinder is 200 degreees higher than the others! I disconnected the vacuum line to the peatcock and the line is wet inside. I turned my petcock to PRI and the temp dropped to the same temp as the other cylinders. If the petcock is in ON when I am riding she coughs, but if it is in PRI she runs great. So I feel very stongly that the petcock is leaking and the fuel is being sucked into #3 carb, which makes it run rich and cough.

Pulled tank sat. and checked petcock. Vacuum line was wet from fuel. Petcock would not hold a vacuum. Took valve apart and fuel was present on "dry" side. Ordered new diaphram for $35, won't arrive until thurs or fri....
Mark

I have not had the chance to ride since the repair...snow, very cold and I had the flu. But it would cough when I reved her on the center stand and now she runs clean. I hope the weather breaks so I can ride.
Mark

Got the chance to ride today. First couple of miles ran bad. Next 10 ran great. got 1 mile from home and she coughed coming off of a couple of stop signs...It wasn't the diaphram.
Mark

Yes I agree with you Norway.... I am going for the f-king coils!!! Have you done the nology coils? Others seem to have good luck with them. I know this supject has been beat to death, but one more lashing won't hurt
Mark

It is suppose to snow tonight and thru the weekend, but temps are suppose to warm up next week. So I will be able to ride or work on the bike (unheated garage).
Mark

Well...it is not a coil problem. The temp has been over 50 so far this week and the bike runs great.
I think I induced this problem by syncing my carbs at a higher rpm than idle and it made the bike "run cold". So when the air temp was in the 30's it never warmed up and cut-out.
This whole problem was a fault that I caused.
Mark

I guess I should retract my last post. I resynced the carbs and it still does it. If the air temp is below 50 she will cough when you roll on the throttle over 50 runs like a champ. So I am still looking for the cause.
Mark

Okay I am going way out on a limb now...
I have noticed that the bike doesn't act up during the first mile of operation. Also, if I pull a little choke it doesn't do it.
Today I rode 50 miles on the interstate doing 80mph (temp in the low 50's and she coughed), when I stopped the hose coming from the cylinder head on LH side of engine wasn't even warm and the radiator wasn't hot either.
This sound like a stuck thermostat ( in full open) not allowing the engine to reach operating temp. The engine is warm when I leave the house, but cools off in the first mile.
I have already change the fuel lines and checked the vent system.
How this for a long reach of logic?
Mark

I ordered a thermostat and it arrived Friday. Installed it this morning. Took 20 minutes. My old t-stat could be opened with finger pressure! New one is tight. Went on test ride and so far so good...
Mark

Still does it. Not the T-stat.

COIL cured it
Thanks for all the input and interest.
Mark

During my troubleshooting I found: a bad thermostat, leaking fuel petcock diaphram, dirty air filter, clogged low speed jet on #2 carb and of course the COIL. My total was about $200 and a lot of cussing and labor hours. Now the bike runs better than ever and it is ready for the summer!
Mark

Drumcore1
I would not recommend adjusting the mixture screws. They are covered with brass caps that have to be drilled off and unless you own an angle drill the carbs will have to be removed. Unless you have a emisions tester you can get things really out of "wack" and induce more problems.

The stock coils are $125-130. You could try mail order through Great Bay, but I don't know their cost...

If your mechanic skills are low get a little help. It is not hard to change a coil, but removing and reinstalling the tank the first time can be taxing.

Mark

Sucking sound?
Try this: get a can of carb cleaner and spray it around the carbs while the engine is running any change in running will show you where the leak is.
Mark