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Why Is My Motorcycle Losing Power While Accelerating?

When do you most intensely experience the incredible power of your motorcycle? Chances are, it’s when you twist the throttle. The feeling of exhilaration you get as your bike speeds up goes hand in hand with the thrill of adventure on the open road.  So when your motorcycle starts losing power while accelerating, it often comes as a rude shock. You may worry that your bike will slow down in heavy traffic conditions, which can be unsafe, or that there is an underlying issue.

Fortunately, loss of power while accelerating usually isn’t anything serious, and it tends to have a simple solution. Common causes are issues with the carburettor, spark plugs, air filter or fuel delivery systems, and you can easily solve them to get back to enjoying your motorbike at its fullest potential!

If you’ve had the misfortune to experience your motorcycle losing power while you’re accelerating lately, you don’t have to deal with the problem alone. Whether you’re a DIY enthusiast or you’ve never picked up a tool in your life, Taverner Motorsports is here to help. We can quickly diagnose and fix the problem. We can also help you prevent problems before they occur, whether that’s by showing you how to change a battery on a motorcycle or carrying out motorcycle carburettor tuning for better power and fuel economy.

When your motorcycle begins losing power while accelerating, what’s likely to be the cause? And how do you fix it?

Causes of Power Loss When Accelerating

Some common causes of your motorcycle losing power while accelerating include:

Carburettor issues

Sadly there’s more than one thing that can go wrong with the carburettor. If you’re losing power when you accelerate, it’s likely this little part that is playing up. A carburettor has the job of supplying the right mix of fuel and air to your engine. Some commonplace carburettor issues include:
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Clogged jets

The carburettor jets are very small passageways that the petrol flows through to combine with the air so that the engine gets the mix right. When ethanol and gunk clog these passages, the engine gets too much air and not enough fuel. As a result, it starts to lose power.

A broken spring

It may be a small part of your carburettor and your whole motorcycle, but when a spring breaks, you’ll feel its impact on your acceleration. The spring opens and closes the butterfly valve that lets air in. A broken spring leads to a motorcycle that runs rich in fuel but has no air to mix with it, causing a sharp loss of power.

Vacuum leak

Faulty gaskets or intake boots that are cracked or loose can cause air to leak into the carburettor and disrupt the air and fuel mixture. This is called a ‘vacuum leak’ and results in your bike getting too much air and not enough fuel.

Clogged air filter

An air filter that’s dirty or clogged with debris restricts the flow of air to the engine and stops it from getting enough oxygen to properly combust.

Bad spark plugs

Slow acceleration is one of the common problems caused by a spark plug that’s too old or in a badly damaged state, along with a motorbike that won’t start. If the plug is too worn out to ignite the spark, your bike won’t accelerate properly.

Slack in the throttle cable

Your throttle cable is what connects the throttle to the carburettor, telling the butterfly valve when to open or close and by how much. Too much slack in the throttle cable will weaken its pull on the valve, causing an imbalanced mix of air and fuel.

Poor timing advance

If you have a fuel-injected bike without a carburettor, your issue is most likely caused by a faulty timing advance. Instead of making sure the spark plugs fire when they need to, a bad timing advance will cause inadequate acceleration, misfiring and eventually stalling.
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Fuel delivery problems

A lack of adequate fuel can be caused by a range of common issues, including clogged fuel filters or leaky injectors.

Poor fuel

Sometimes all it takes is poorly selected or dirty fuel for your engine to start losing power.

Faulty oxygen sensor

Your exhaust pipe’s oxygen sensor measures the fuel you haven’t burnt. Your bike’s ECU collects this data to determine the right fuel amount for your bike to perform at its best. If it gets the wrong information, it will give you the wrong amount of fuel.

Solutions to Fix Acceleration Loss

If the accelerator on your motorbike is losing power, the good news is there are relatively easy ways to fix it. If you get stuck, get in touch with Taverner Motorsports. We can help you with everything from how to change a battery on a motorcycle to restoring a classic bike.

Some of the most common solutions to a motorcycle losing power while accelerating include:

Clean your carburettor

If a plugged-up jet is your problem, you’ll need to take your carburettor off and take it apart. Remove the float bowl, take out the jets and spray some cleaning fluid through it to clear the blockage. You can also blow some compressed air through. Make sure you have the right tools for a job like this and the skills to work on your carburettor without causing problems.
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Replace damaged parts

If your carburettor problems are caused by a busted gasket or a broken spring, it’s easy to simply replace these faulty parts.

Tighten your throttle cable

There’s a way to check if extra slack in the throttle is your issue. With the motorcycle off, twist the throttle. If the valves don’t open completely, you’ve probably got some extra slack. You can tighten it with the tightening nut just inches above the knob that connects the throttle cable to the carburettor.

Clean your spark plugs

Dirty spark plugs are a common cause of poor acceleration, and luckily, they’re not too hard to clean. Take the spark plugs off the bike, use a wire brush to remove debris and dirt from them, rinse them with gas and allow them to dry before re-assembling them.

Clean your air filter

Take your air filter from the bike, use an air gun to blow the debris out of it and then rinse with warm water until every trace of dirt is gone.

This list is just for starters. There are several more reasons why a motorcycle can start losing power while accelerating. If you’re struggling to find a solution, take your motorbike into Taverner.

Ways to Maintain Motorcycle Power

Here are some steps you can take to prevent your motorcycle from losing power while accelerating:

Restore Your Motorcycle’s Power with Taverner

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If you’re tired of your motorcycle losing power while accelerating, Taverner can soon have it running perfectly again for you.

With 40+ years in the industry and excellent relationships with global parts suppliers, no job is too large or too small for Taverner. We can protect your bike with a motorcycle carburettor tuning or carry out high-level performance work.

Whether it’s how to change a battery on a motorcycle or how to custom-build an impressive bike, contact the Taverner team.