#1,2 not firing

[nichols750]

OK weird situation,
My bike has sat for the last week. It was running great before that. This morning I go out to start it and it runs like crap, keeps dying, no power, no idle. I am late for work so I happen to have a bottle with cleaner in the garage so I squirt the pipes to see if all cylinders are firing. #1 and 2 are cold and 3 &4 are hot. :? I don't know what is going on, why would those two be cold. i'm getting gas, I have a clear gas line. and it was running good a week ago.
Help GS gods of knowledge.

[Billy Ricks]

Weird that 1 & 2 would go cold together, pretty much rules out ignition. If it has a pair of fuel lines branching off the main line one of them could be pinched.

[nichols750]

no just one fuel line into the carbs.

[Billy Ricks]

Plug wires to those two didn't get crossed by someone playing a joke by any chance?

[nichols750]

i doubt it it's just been sitting in my garage the whole time, my wife won't touch my bike, and I don't think my three yr old could pull the wires off.
but, I'll check

[Dave8338]

Did you leave the bike on the side stand for a day or two? Had that happen to me about a month ago and that was the first and last time I've used the side stand. :shock:

[nichols750]

no it was on the center stand

[kurifu]

This could still be the ignition... don't rule it out because it is not happening to paired cylinders.

Check your plugs for a spark, pull them out and ground the head, you should get a fat blue spark if it is running well.

Might also be a break in your HT wires if the spark is substandard, replace the spark plugs if you don't get a good spark and get a spark plug tester from walmart, they are cheap; you run them along the length of your ignition wire to mke sure there are no breaks in it.

Check that you are getting fuel like above too as there could be issues with the carburators, also make sure the plugs are not fouling out.

The ignition system in my opionion is a whole lot easier and cheaper to check than the carbs, so check them first!

[chef1366]

Is the fuel tank clean? I'd pull those carbs and clean them. Also check the petcock. Check those two float bowls and see if there is gas in them. I can't see it being ignition related since #1 and #2 are unrelated cylinders. One coil fires #1 and #4 and the other fires #2 and #3.

[relic-rider]

This could still be the ignition... don't rule it out because it is not happening to paired cylinders.

Check your plugs for a spark, pull them out and ground the head, you should get a fat blue spark if it is running well.

Might also be a break in your HT wires if the spark is substandard, replace the spark plugs if you don't get a good spark and get a spark plug tester from walmart, they are cheap; you run them along the length of your ignition wire to mke sure there are no breaks in it.

Check that you are getting fuel like above too as there could be issues with the carburators, also make sure the plugs are not fouling out.

The ignition system in my opionion is a whole lot easier and cheaper to check than the carbs, so check them first!

I agree to check the ignition first. The plugs may have just fouled out. One other scenario that could happen on 1 & 2 is that the hold down clip on the head cover could be shorting the wires out if it rubbed thru. Not likely, but my rule of troubleshooting is to check easy things first. Then delve into the carbs. Maybe some crap got into the left side of the main fuel T on the carbs, causing a blockage to 1 & 2 carbs. Open the bowl drains to check for gas flow.

[nichols750]

turned out to be a pair of bad plugs, put new ones in and it runs like a champ.

[chef1366]

The winner is Dan T!