Question about Honda Motorcycles
Hi, Will engine "BOG" is mainly caused by a rich air and lean fuel condition but it can also be caused by a lean air and rich fuel condition this situation rarely occurs and is only caused by the misinformed weekend warrior that owns a toolbox. If the bike has been sitting for months or years you will have to completely disassemble the carburetor and submerge the parts (except rubber parts) in "Carburetor Dip" It usually comes in a gallon bucket with a wire mesh basket that can be purchased at any automotive store. If it is not the above scenario then the following explanation will apply.
The more you open your throttle the more vacuum you are creating in your carburetor venturi and your intake manifold. When you are operating at higher RPM any unmetered air that leaks into your system can become more obvious.
Unmetered air is the air that is getting into your system after the fuel has been delivered. If you have unmetered air getting into your system between the butterfly/slide of the carburetor and the cylinder head this will create a lean condition.
All of the rubber components of the fuel system like vacuum hoses and intake manifold that you mount the carburetor to are made of rubber. If none of these components has been changed they are more than likely highly degraded and probably cracked in places to allow unwanted-unmetered-contaminated air into the combustion chamber. Check all of your vacuum lines and vacuum plugs for carburetor synchronization. The vacuum plugs are in the head just after the rubber intake manifolds. The petcock has a vacuum line as well as part of the emission system.
1. Check the intake manifold for fissures.
2. Ensure the bands used to tighten the manifolds down on the intake are secure and have not bound up the manifold.
3. Make sure air box fittings are not warped and fit completely over the carburetor.
Your airbox is metering air and is the first step in the process of consuming air and fuel. The system requires the resistance of the air filter in order to get the proper vacuum to "SUCK" the fuel out of the float bowl and create the proper venturi effect.
Improper mounting and sealing of the airbox will create a small lean effect. This might seem like no big deal but you are inviting dust and debris in your engine that is doing slow damage by not having proper fitment. Fix it so you know it's not contributing to your issue. Pick the low-hanging fruit first.
Do not go and start adjusting anything at this point. It ran fine before. There is something wrong with the assembly or a component. Do not adjust your floats. Get it back to where it was. The moment you start tweaking everything is the moment you lose OEM settings which are a must-have for fine-tuning and maximum performance.
Fine-tuning your carburetor and multi carb syncing come at the very end following the proper procedure established by the Carburetor Gods.
For more information about your issue and valuable "FREE" downloads that you will need for viewing or printing please click on the blue links below. Good luck and have a wonderful day.
Posted on Jun 02, 2020
IT COULD BE THE SPARK ARRESTOR IS PLUGGING UP
Posted on May 18, 2020
Well this could be in your timing. As cars get some miles on them the timing chain stretches therefore causing you car to lose alot of power.So you may want to have your timing set on this car. Also I had a taurus that had a bad torque converter, and it lost alot of power on hills and under loads, also when i gunned the gas pedal. so try the timing first. Hopefully you dont have a bad head gasket or a cracked head these symptoms you are describing are all signs of head gaskets or blown heads
Posted on Sep 04, 2008
Do you have the H and L adjuster screws on the carb? If so, then normally I'd back out a little bit on the L (low speed side of carb) The instructions for adjusting carbs, years ago, on 2-stroke, say to back out on the L when motor will not rapidly rev up. Most 2-stroke carbs have these 2-jets. The L is for gas to pass to motor with butterfly throttle plate closed. When opening throttle plate, there is a sudden rush of air, at first, and this L adjustment is allowing enough gas to pass for motor to begin to rev. up. Then the gas will also flow through another small port H, usually a small brass tube in the venture area (smallest diameter section of carb). You adjust the H with the throttle wide open, motor revved up. Turn either in or out slightly till highest RPMS reached, motor smooth and fast, then turn H out about 1/4 turn. The idea is to run motor slightly rich for highest HP when under load (cutting). Hope this helps
Posted on Nov 19, 2008
the fact that it idles with the choke on indicates that fuel mixture is the problem here remove the mixture screw completely check that the o ring seal is not damaged & that the end of the needle is not worn or bent if either of these conditions are obviouse replace the damaged or worn parts general rule of thumb with mixture adjustment is 1&1/2 to 2 turns out give it a try
Posted on Feb 23, 2010
I have 1999 Dodge 1500 gas motor. It has a high idle and when I let off the gas it stalls out. The truck also has a engine light on. What do I do??????
Posted on Aug 05, 2012
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