Posted on: 16 February 2016
When you're having trouble with your motorcycle's carburetor, it's important to isolate the source of the problem before you start trying to make changes. Motorcycle carburetors are fairly simple but precise devices. Here's a look at some of the most common issues you might encounter and some tips to help you deal with them properly.
It's Running Too Rich
When your bike is running rich, that means that the carburetor is injecting too much gasoline into the combustion mixture. Some signs that can indicate that the bike is running rich include sluggish or slow acceleration, poor gas mileage, black soot buildup on the tips of the exhaust pipes and a gasoline odor when the bike is idling. You may even notice black tips on the spark plugs and intermittent stalling.
Sometimes, your bike may run rich simply because you haven't replaced the air filter. A dirty air filter can hinder air flow, so the mixture that would otherwise be balanced isn't getting the right amount of air, causing it to be too rich. You may also have this problem if you replace the exhaust or the carburetor with an aftermarket model that isn't quite the proper fit. Finally, it may happen if the fuel level in the float chamber is set too high.
It's Running Too Lean
Running lean is a condition where the carburetor is allowing too much air in the fuel mixture. If your bike is running lean, there are a few things you may notice. For example, if your bike starts backfiring when you close the throttle or jumps on acceleration, those are indications that you may have a lean mix. In addition, lean-running engines will develop white residue on the spark plugs and may even develop a light grey or white residue on the tip of the exhaust pipe. You may also notice that you need a lot of choke to start the bike and keep it running properly, or you might see bluing on your chrome down pipes.
Running lean is often a direct result of replacing the exhaust, air filter or carburetor with an aftermarket product of a different size. You may also experience a lean mixture if you have the fuel level set too low in the float chamber. If you haven't made any changes to the bike and the lean running is a new issue, it may mean that you've got a leak in the header pipe or the inlet manifold. You'll want to take the bike to a mechanic to have that evaluated, though.
It's Been Improperly Adjusted
Another common cause of problems with a motorcycle's carburetor is improper adjustment. If your bike was running fine before and then you tinkered with the air to fuel ratio screw, you may have adjusted it improperly and now have a poor mixture. As an alternative, you may find that the vibration in the engine could cause the adjustment screw to shift. If it's loose and moving due to vibration, you'll need a mechanic to help you.
However, there are a few key indications that there's an adjustment problem in the carburetor, whether it's the adjustment screw, the float setting or any other. For example, if the engine is running generally rough, misfiring or seems erratic, it may be an adjustment issue. Your mechanic may suggest that you perform more frequent engine maintenance to avoid problems like this. The more often you have the engine inspected, tuned up and maintained, the easier it will be to catch adjustment issues caused by vibration before they create any engine response issues.
No matter what the source of the issue is, problems with your motorcycle's carburetor can cause havoc on the engine. With the tips here and the help of a mechanic, such as Monarch Honda, you can identify and deal with these issues easily.Share