Can't get over 80 mph

[KEITH KRAUSE]

I have not looked for the vents between carb. Ok I know this is going to sound like I do not know what I'm doing but how do I check the tubes between the carb. Other then looking for cracks is there something eles I need to do. Is the smaller tube on the petcock a vacum line.

If you mean the two floatbowl vent lines, just make sure they are clear and not kinked. You should be able to blow into them. Cracking won't stop the venting ability but water may seep in if you wash the bike.
The smaller nipple/line on the petcock is for the vacuum. It goes to carb #2.

[gcraig]

It's been raining here so I have not been able to work on the bike (no garage). I had to order an o-ring for the petcock it should be here by Friday or maybe Thursday. Planning to ride to the Woodland north of Houston this weekend. I did pull the air filter box and when I looked in the connection to the carb. there was a lot of gas on the air box connector to the carb. Any ideal how the gas could accumulate there. I have had the gas tank off the bike for about a week but before that it sat for about week with the tank on the bike. All of the connector look good and the clamps where all tight. I did find out that I have a K&N filter# G-103A4 or SU-120. I have read about having to re-jet the carb. if you put a K&N filter. If this is true then how do I make sure the carb. are jetted correctly. Sure hope I do not have to take the carb's apart for this I sure hate to have to buy a carb. kit.

[KEITH KRAUSE]

I don't think you need to re-jet for the K&N filter.
When the bike is running right, take some plug reads to be sure. If the plugs look lean, we'll help you with the jetting. I doubt it would involve more than a step up on the mains and a little richer on the mixture screw settings.
If you've got gas in the airbox, it would be the petcock, or a leaking float needle valve, or an o-ring/gasket for the float needle valve seat, or a float not operating correctly or the float level needs adjusting.
Your previous test of the petcock sounded like it was good. To be sure, take the fuel line off and vacuum line off the carbs and plug/pinch them closed. Let the bike sit as it did and check to see if ANY gas collects. If it's easier to do, leave the lines connected at the carbs and get some extra lines and hook them up to the petcock.
If it's the carbs, you may be lucky and just find some dirt interfering with the float needle. If there's a deep enough groove worn around the tip of the valve, or the spring is weak, replace the valve. Also check the o-ring or gasket for the valve seat. The floats should move smoothly and float in a bowl of gas. After being held under they should still float and not have any gas inside them when you shake them. If all this checks OK and the petcock is not leaking, you would need to check the float height. This would require taking the carbs off.

[gcraig]

I checked the vacuum and fuel hose there ok. I have not done the bowl check yet. I think I?ll wait until the middle of winter to do the bowl check. Well I have the air cleaner and petcock back together. Who ever had it be for me took a hose and cut it in half and screwed it to the top of the air cleaner to seal it to the air box. I cleaned the K&N filter and replace the rubber hose with weather strip and put the air cleaner back on the bike. Made sure it sealed. I got to ride to work this morning and go up to 80 ? 85 and held it there for a short time short road, it kind of missed fire about 75 and then got to 80. It did not shut down it kept going Maybe this weekend if its not to cold I will test it more. I think the next thing is to replace the coils to make sure the plugs are firing well.

[duaneage]

test

try this

Take it up to around 70 for a minute or so, then crank it up until you have your acceleration problem. As soon as it begins to miss or bog or whatever, kill the engine and coast to a stop .

Pull a plug and see what they look like. Fouled plugs indicate a coil problem, white plugs indicate a lean condition. Does the engine ping if you accelerate from 45 - 60 in 5th gear? Fuel delivery problems will cause pinging at low manifold vacuum, not just high speed.

Do the plug test on a clear road and make sure you can safely pull over and check the plugs. I did this for Holley carbs to get the jetting and secondary opening right, also power valve testing.

These things are nothing more than overgrown lawnmower engines on two wheels after all.

[gcraig]

Thanks duaneage
I will try that this weekend if its not rainning here it is forcasted to rain.

[gcraig]

Ok I got to ride this past weekend 11/14/04 (my son birthday 12yr old) and I got up to 85 and held it there for about half a mile and it held. I think my problem was the dirty air filter. I would like to say thanks to all who have responded to this problem it was a great help. It?s good to known that there is a group of people willing to help.