Can running out of gas lean one cylinder

[70SSElky]

First post here and tried a search but all of my search words are too short so I need to ask the banshee guys here. I have a buddy that just rebuilt his banshee a couple of trips ago and it has been running awesome. It is a 4mil with a few mods but nothing real radical. Been running great right up untill..... he ran it out of gas. One cylinder plug looks great, the other...... white with what he explained to me sounded like aluminum. Sounds like he popped a hole in the piston but not sure, we will know later when we pull it down.

 

Bottom line is, can this happen from running the bike out of fuel. Can the one cylinder keep getting enough fuel to run and not the other.... causing the other to go lean?? He said it was running like crap at the end, I wonder if that is when the one side was leaning out.

 

The main reason I am thinking this way is he ran out of fuel on the main tank, bike was running great and then quit, switched to reserve, kept going untill bike quit again. Now.... bad cylinder.

[trex banshee]

my guess is if he just flat ran out of gas it didn't cause this problem. However it is not good on the rings or anything else to run them out, that is how everything is lubricated. Now it could have been from that one cylinder not getting enough fuel while the other was running strong. This could have been from a clogged main, or it produced and air leak somewhere on the side that burnt up.

 

But if he just ran out of gas it would have died and both sides should look the same.

[Screaming Yellow Zonker]

What I have experienced with my 4mm is that at wide open it will drain the carb bowls causing a lean condition. My suggestion would be to go to a larger carb setup. If you don't want to go too big get a set of Blaster carbs (28mm) they will fit into the banshee boots with a little lube and will provide you with more fuel for those hard rips.

 

Also I agree running out of fuel will shut down the engine not just one side.

[badassbanshee479]

if you are running a tee in the fuel lines you will run one carb out before the other. its because the fuel takes the path of least resistance.

 

if he ran out of fuel on a wide open run, it will more than likely burn it down.

also a blown head gasket can cause a lean condition and make it go boom!

[70SSElky]

Thanks for the quick responses! I must say that I tend to agree with you and am leaning towards an airleak myself.

 

It just seems strange that it happened when he ran out of gas. It could just be a coincidence but the timing of it all just got me to thinking, so thats why I asked.

 

Thanks for letting me know about draining the bowls...... I will talk to him about that. It does have pipes, air cleaners, light port etc. and yes it is a fuel hog. (That's why he ran out of gas) LOL

[70SSElky]

He was on sand highway at Glamis, hauling a$$ back because he knew he was low on fuel..... I am sure he was 4th gear motorin' both times he ran out. (main tank and reserve)

[dajogejr]

if you are running a tee in the fuel lines you will run one carb out before the other. its because the fuel takes the path of least resistance.

 

Agreed...but the other cylinder won't run long after the first one quits...we're only talking 20 seconds of run time, if that...as much fuel as in the line....

 

Sounds like he ran out of fuel period, and leaned it out detonating it.