How long does a petcock last?

[amontyg]

My bike has recently started an odd behavior. It will suddenly die while stopped and idling at stoplights. When I try to start the bike nothing happens. However, my battery is getting old (I need to get a new one, I'm just procrastinating), so it doesn't have enough juice to just sit there and turn the starter forever. I usually only get one or two shots at starting my bike, then it's time to push start the thing. When I roll the bike off the road and push start it it will generally start right up.
This seems similar to the problem I had several years ago with the petcock. I put a new petcock on the bike then, that was probably four years ago now. When I had that problem, however, the bike would quit on the freeway running at 6000 or so RPMs. This is only happening at idle, around 1000 RPMs.

As far as a maintenance history, the carbs were rebuilt with new O-Rings four years ago as well as new carb boots and O-rings installed at the same time. At the beginning of this year I did a valve adjustment, and replaced the spark plug caps. The carbs have not been synchronized for a couple years now.

[Larry D]

A petcock should last that long easily. I turn mine to the different positions from time to time, just to keep it moving. I don't know if this actually does anything, but, it makes me feel better.

The first thing I'd do is get a new battery or at least ensure the one you have is fully charged.

[BassCliff]

Hi,

Was your replacement a new OEM petcock? They should last 20 or 30 years.

If your battery is shot then the voltage at the coils is probably reduced and the spark is less than it should be, causing difficult starts.

To run its best, everything on your bike has to be properly maintained; gas (clean carbs, functioning petcock, etc), spark (battery, charging system, etc), and compression (valves, rings, etc).


Thank you for your indulgence,

BassCliff

[tom203]

I bet your petcock is fine.I think your system voltage is falling off excessively as you drop to idle. Get a new battery and test your charging system- also, clean the connections while you're at it.

[mike_of_bbg]

I was going through much the same thing for a while.

+1 on the coil voltage. With a weak battery when you're trying to crank it you'll probably have really weak spark. Push starting will be easier on your coils because the starter isn't draining voltage at the same time. Obviously your battery is shot so replace it but check the coil voltage again after you do. Mine was still low, and I did the coil relay mod. Check your plug caps also to make sure they're not putting up too much resistance. Also test your charging system and make sure it's up to snuff.

Once I changed those re-starting was much easier but I'd still get a hot idle stumble. The rest was mixture screws and carb sync. Too rich running plus one of the carbs was too closed at idle. This caused the plug to carbon foul and the bike to die at hot idle.

Good luck!

[JEEPRUSTY]

My petcock is 26 yrs old.
It is double plus good.
The useful life depends on fuel quality and other factors.