Replaced Petcock / Still Problems

[Guest]

Thought I did it. I replaced the Petcock and everything seemed great.... for a day. I'm at half a tank of gas now and she just won't turn over. Starter works, engines starts sputtering for a sec, I twist the throttle.......she just won't catch. Sometimes can get her going, but my last 3 attempts, nothing. Very frustrating. And if I do get it her running, and warm her up...she is fine...until I turn her off and try again...then I'm at the risk of not starting.

So where am I at now

Valve Adjustment? What do I need to do this.....should I print out BC's valve tutorial?

Carb clean?... Man...I'm such a novice at all this and don't have a garage. My bike is on the street (with cover).

Is it something easy that I'm missing?

help!

[Dave8338]

Is it possible that the fuel line is too long? If it loops up past the bottom of the tank, there is a chance that you have an air lock condition. Was the bike showing any of these signs prior to the petcock replacement?
Have you verified that you have fuel flow in the prime position? This shouldn't be too difficult of a problem to solve. :-D

[maro]

Well, not sure about the air lock condition. the bike started and ran fight away following the petcock replacement. When I change the petcock I did not change the lines, just the petcock assembly itself.

As far as Prime, I believe it is working. I know this because my (and this has been a problem before replacing petcock) breather hose leaks gasoline when I leave the Prime on for a bit.

[Dave8338]

Sounds like you may have a problem with the needle and seats not sealing. Have you had the carbs apart yet? It is notorious for the CV carbs to need attention if they've not been used consistantly.

What bike are we talking about here? Year, Make, Model?

[maro]

Year, make and model are in my siggy. 81 650G

hmmm. Carbs. would valves be easier to check? If so, is there a chance that is the culprit?

thanks for all the help

[Dave8338]

The quickest way to determine if the valves are at fault, would be to run a compression test. Numbers in the 160+ psi. range and <10 psi. variance would be fine. If it ran great for a day and then started having the issues that you describe, it is unlikely that it is valves / rings, but you won't know for sure unless you run a compression test (should be done on a warm engine at WOT).

[jpaul]

If you haven't done a valve adjustment since getting the bike, do one. It may or may not be the cause of your problems, but it's best to eliminate that as a possible source. I would put in fresh plugs if that hasn't been done. These may not be the problems, but you're better off knowing that the simple, regular maintenance things are OK before working on things that take more time and/or money.

[Dave8338]

GREAT POINT...I often overlook that, based on assumption and you know what is said about that word or it's root. :-D