Is your motorcycle bobbing on acceleration? It’s not a fun position to be in. In this article, we’ll break down the causes and present you with ways to avoid your motorcycle from bogging. Let’s get right into it!
A motorcycle that bogs somewhat noticeably upon acceleration is probably suffering from a lack of engine power or compression, along with a less likely possibility of a misfiring sparkplug.
Engine power and compression problems can be diagnosed by giving the bike some gas, releasing the clutch quickly, and looking at how much RPM increase there is as you accelerate.
If the bike bogs down and then pick up speed for a second or two before bogging down again, it’s probably just a spark plug that needs to be replaced. A new replacement plug will likely fix the problem quickly.
However, if there’s no increase in RPM as you give more gas, chances are your engine is suffering from a lack of power or compression.
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Is it a compression problem?
Compression problems are the most likely culprit, in this case, so you’ll want to have your mechanic check it out. If you want, you can check for compression problems yourself.
How to check for compression problems
Locate the spark plug(s) on your engine. Remove the spark plugs and take them to an auto parts store that tests them for free. Some stores will give you a printout of any problems found, while others will simply tell you if they’re bad – in which case you might have to replace all of them if they’re worn out.
Once you get your spark plugs tested, you’ll know the condition of your engine’s compression. If it’s good, then chances are that there’s a fuel supply problem or possibly an ignition problem. Either way, this isn’t something you should try to fix yourself – take it to a mechanic.
Below, we’ll go through the different reasons for bogging in-depth and giving you tips on how to fix these.
Ways to avoid motorcycle bogging
Proper Carburetor Maintenance
Your motorcycle’s fuel supply is controlled by your carburetor, which meters the amount of air and fuel entering your engine.
A properly tuned carburetor will run perfectly under most conditions. But if it isn’t tuned correctly, you’re bike may have an insufficient supply of gas, especially as you’re accelerating from a stop.
Clogged Jet
This is the most common cause of power problems on motorcycles. A clogged jet will reduce the amount of fuel entering your engine as you accelerate, possibly causing a bog. You’ll need to clean or replace your carburetor’s jets to fix this problem.
If your motorcycle has an air-induction system, ask a mechanic to help you remove and clean it out.
Dirty Carburetor
If there’s too much dirt or debris in your carburetor, it can prevent proper operation and cause power problems.
This is especially true if your bike has been sitting for a while. When fuel goes bad, it can create gummy-like residues that stick to the inside of your carburetor.
Before putting your motorcycle back into service after it’s been sitting for long periods, drain the gas tank completely and then run the engine until it dies. Next, clean all of the dirt and other gunk out of your carburetor.
Broken Spring In Carburetor
A broken spring within your carburetor will reduce the amount of fuel entering your engine as you accelerate, possibly causing a bog.
If there’s no gas getting into your engine, this is a common problem that happens to some models of motorcycles. It can often be easily fixed by replacing part of the carburetor with a new one from the manufacturer.
Air Leaks In Fuel Line(s)
There are several fuel lines that run from the gas tank to your carburetor, and it’s possible for them to develop leaks. If you have a leak in one of these lines near the tank, gas will spill out instead of getting into your engine.
If this happens, you’ll have to replace the faulty line or lines. They’re usually rubber and they can deteriorate over time as a result of exposure to gasoline.
Gas cap installation
If you’ve just filled up your gas tank and the engine bogs down upon acceleration, it could be that your gas cap is too loose or not on all the way.
Check to see that it’s secure and fits properly. If you’re not sure, try tightening the cap or replacing it with a new one.
Tighten The Throttle Cable
If there’s no increase in RPM as you give more gas, your throttle cable may not be adjusted correctly.
Take it to a motorcycle mechanic or tighten it yourself if you know how to do it. You might even need to adjust how far the slack is taken up on your chain so that enough power is transferred to the rear wheel for acceleration.
Improve Timing Advance
If none of the above works, it could be that you need to improve your timing skills This is due to the fact that your spark plug wires are probably worn out.
The wire insulation slowly wears down over time, which can affect how well your spark plugs fire when you open the throttle to accelerate.
If they’re old, you might even need to replace them.
Types of motorcycle bogging
Types Of Motorcycle Bogging
Lean Bog
When a lean bog occurs, the problem is most likely with the air/fuel mix. The engine may be receiving too much air and not enough fuel, or vice versa. A lean condition can lead to serious performance problems in even the finest motorcycle engines.
Rich Bog
A rich bog is nearly the opposite of a lean bog because it means that there’s too much fuel and not enough air. A lean condition is usually accompanied by a popping sound out the exhaust, while a rich condition will emit black smoke from the exhaust.
Gear Bog
A gear bog occurs when there is a problem with the transmission. Possible causes include a poorly adjusted clutch, dragging clutch plates, worn gears, or a damaged shift drum.
Low-Speed Bog
A low-speed bog occurs at very small throttle openings and high RPMs. For example, if you opened the throttle of a motorcycle that was in first gear at a stoplight, the engine might bog down.
High-Speed Bog
A high-speed bog is just what it sounds like–a problem that only occurs when you’re going very fast. If you have to adjust your throttle output significantly as you go through the gears of a motorcycle, your engine probably has some sort of high-speed bog.
Conclusion
As you can see, there are many reasons why your motorcycle may bog on acceleration, there are also a lot of different types of bogging. To fix the problem, you should identify the cause and then take action accordingly.
Your mechanic will be able to help with this, but if you’re keener to get it fixed yourself – make sure to ask for further advice on forums or in the comment section below.