Running lean? Running rich?
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Running lean? Running rich?
Man, i'm posting a lot today. 
Anyway, i've been thinking about this.
My bike pops out the pipes a little bit whenever i'm going down a hill and just letting the engine hold it back, and I just figured it was running a little rich, and that was the extra unburned fuel making its way out the exhaust, and igniting in the pipes. I got the idea the other day to see what happened if I pulled out the enricher while it was popping..I did, and the popping quit..pushed the enricher in, and the popping came back. Now this, to me, makes no sense. Doesn't the enricher just dump a lot of fuel? If that's the case, it should have popped MORE, right?
Anyway, i've been thinking about this.
My bike pops out the pipes a little bit whenever i'm going down a hill and just letting the engine hold it back, and I just figured it was running a little rich, and that was the extra unburned fuel making its way out the exhaust, and igniting in the pipes. I got the idea the other day to see what happened if I pulled out the enricher while it was popping..I did, and the popping quit..pushed the enricher in, and the popping came back. Now this, to me, makes no sense. Doesn't the enricher just dump a lot of fuel? If that's the case, it should have popped MORE, right?
Road Warrior
Joined: Nov 2006
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From: Deltona, FL
RE: Running lean? Running rich?
Well, the enrichener does indeed dump alot of fuel into the jugs, so on the surface it may not make sense. You most likely are running a little rich, and you are correct that the popping is the unburnt gas exploding as it runs through the pipes. However, in order for detonation to take place, the fuel has to be mixed with the air in a mist. If you dump too much fuel, the fuel will not be properly vaporized and will actually be condensed to where it will not mix with the air and therefore, no detonation.
If you leave the enrichener on long enough and watch your pipes, you will actually see liquid fuel running out of the end of your pipe, most likely.
Make sense?
If you leave the enrichener on long enough and watch your pipes, you will actually see liquid fuel running out of the end of your pipe, most likely.
Make sense?
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RE: Running lean? Running rich?
Thanks Phrogman, I was sort of thinking that too, but wasn't sure. I know this because i've experimented with building several aerosol powered cannons and such, and if you mix too much proppelent, it won't fire because there isn't enough oxygen to allow it to. Thanks again..
Tourer
Joined: Jun 2007
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From: Northern NJ
RE: Running lean? Running rich?
ORIGINAL: michaelbarry
Thanks Phrogman, I was sort of thinking that too, but wasn't sure. I know this because i've experimented with building several aerosol powered cannons and such, and if you mix too much proppelent, it won't fire because there isn't enough oxygen to allow it to. Thanks again..
Thanks Phrogman, I was sort of thinking that too, but wasn't sure. I know this because i've experimented with building several aerosol powered cannons and such, and if you mix too much proppelent, it won't fire because there isn't enough oxygen to allow it to. Thanks again..
Running your bike with the enrichening circuit on while the bike is warm, is a good way to create carbon build up in your motor. At the very least you will certainly foul your plugs.
Your bike is not running rich. Just the opposite. Popping in the pipes on deceleration means it is running lean while in the off throttle position. Just the fact that you dumped in fuel and it stopped it is clear indication of that. I dont know how your bike is running , but from your other thread where you stated that your pinging (pre-detonation) I would say your running lean.
Change your plugs with fresh ones. Warm your bike and go for a ride. While in gear (about 3000 rpm)hit the kill switch (somewhere safe) and pull over. Take out your plugs (when they cool off..lol) and see how they look. They should have a nice coffee colored tint to them. If they are white, you need to jet your bike accordingly.
Start with fresh plugs and read them.... Then worry about the next step.
Road Warrior
Joined: Nov 2006
Posts: 1,699
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From: Deltona, FL
RE: Running lean? Running rich?
Well, we cannot properly diagnose his problems without looking at the bike, but detonation could also be caused by rolling on the throttle while the bike is at a low rpm and not necessarily indicate a fuel jetting problem. It may still be fuel jetting, but the question of running lean or rich will have to be diagnosed by a tuning professional to get to the true answer.
It could honestly be either.
It could honestly be either.
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RE: Running lean? Running rich?
Thanks for the replies Moondog, and OhioMoto...
Moondog, i've never jetted a bike carb before. I really need a damn service manual for this thing, but i'm just getting back on my feet from a 3 month gap between jobs..I will be able to afford one pretty soon.
Moondog, i've never jetted a bike carb before. I really need a damn service manual for this thing, but i'm just getting back on my feet from a 3 month gap between jobs..I will be able to afford one pretty soon.
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Tourer
Joined: Jun 2007
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From: Northern NJ
RE: Running lean? Running rich?
ORIGINAL: michaelbarry
Thanks for the replies Moondog, and OhioMoto...
Moondog, i've never jetted a bike carb before. I really need a damn service manual for this thing, but i'm just getting back on my feet from a 3 month gap between jobs..I will be able to afford one pretty soon.
Thanks for the replies Moondog, and OhioMoto...
Moondog, i've never jetted a bike carb before. I really need a damn service manual for this thing, but i'm just getting back on my feet from a 3 month gap between jobs..I will be able to afford one pretty soon.
If it isn't done, get a kit and follow the directions. It's straight forward and pretty simple. Once you do it, your bike will be less prone to pre-detonating and as a bonus will run cooler.
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