Honda Motorcycles Carburetor Problems (Solved & Explained!)

The carburetor is one of those components that the typical motorcycle simply cannot do without.

Even as some newer models move to electronic injection, the majority stick with carburetors as the tried-and-tested method of mixing air and fuel and providing the engine the fuel/power it needs to push a motorcycle forward.

This article explains “most-common Honda Carburetor problems”…

How Does A Carburetor Work?

A carburetor takes in airflow and then uses the Venturi Principle to narrow the intake tube, decrease air pressure in strategic locations to draw fuel into the airflow to create the right mixture of air and fuel needed for the internal combustion process.

Pressure might drop by 5psi as it passes more quickly into the narrowed section of the pipe, which moves the fuel effectively without using complex injectors.

The Symptoms Of A Honda Failing Carburetor:

Honda still makes extensive use of high-quality carburetors, but even they can fail sometimes.

Luckily, we don’t have to be shocked by a struggling or failing carburetor because there are nearly always symptoms that one can detect.

On a Honda motorcycle, if your carburetor is failing, you might notice the following symptoms:

  • Reduction in engine performance
  • Sputtering
  • Black exhaust smoke
  • Overheating

Hondas are generally very reliable for starting no matter what, but if you’re out on the road and experience a loss in acceleration or a feeling of reduced power and performance, then this is quite likely caused by the carburetor, especially if it happens rather suddenly.

It doesn’t always take much to create blockages and buildups within the jets and other components, and that’s why one day the carburetor might appear fine but then symptoms appear the next day.

It’s important not to be alarmed by the emergence of this symptom or any other.

A Honda carburetor can invariably be restored to health after a good cleaning and inspection of the individual components.

Another symptom that there is a carburetor problem is sputtering from the engine, which is caused when blockages make the air/fuel mixture too light.

Not enough fuel is being brought in, which means the engine doesn’t get enough power and it sputters as a result.

Conversely, the opposite can happen too on Honda carburetors, with too much fuel making it through

– caused by a big drop in pressure that drags more fuel than is intended –

which burns through your fuel quicker and leaves a trail of ugly black smoke in your wake.

Overheating can occur as a result of sputtering since it’s mostly connected with the engine not getting enough fuel.

As it does, it works harder to compensate, which causes it to overheat.

An overheating engine can cause irreparable damage, so you’ll want to take that symptom seriously.

Are Honda Carburetors More Prone To Fail Than Other Motorcycles?

No, they are not.

Honda motorcycles in general rank very highly for reliability among the world’s most popular brands.

It is second only to Yamaha for overall reliability.

Specifically, the carburetor is also extremely well constructed on all Honda models and while it does suffer some occasional difficulty, it is certainly not more prone to fail than other brands, in fact, quite the opposite.

The failure rate of Honda motorcycles and carburetors is only 12 percent.

That’s extremely low.

In contrast, Triumph has a failure rate of 29 percent and BMW 40 percent.

The most common reason for carburetor failure in the Honda can be traced back to a lack of proper maintenance and care for the unit, far more so than any other fundamental or technical failure on the part of the Honda carburetor.

How Long Should A Honda Carburetor Last?

The carburetor is not listed among Honda’s wearing parts, although some of the smaller components within the carburetor were indeed more susceptible to wear and tear.

The carburetor unit can therefore be maintained to last the entire lifespan of the Honda motorcycle.

The key to a long-lasting carburetor is proper maintenance and specifically cleaning the carburetor, keeping the jets clear and the gaskets properly sealed and repaired.

When this is done well, there’s nothing at all that should shorten the life of the carburetor.

Indeed, many carburetors outlive their motorcycles, being collected when the bike is eventually scrapped and resold as used OEM Honda parts.

What Honda Models Are Likely To Have Carburetor Problems?

Honda has a very eclectic range of motorcycles, and among their huge range there are perhaps 5 models which are known for ever having some problems with the carburetor, and they are:

  • Honda VT
  • Honda Valkyrie
  • Honda Goldwing
  • Honda Foreman
  • Honda CB

The VT models are most affected by long periods of inactivity, which is unfortunate because many of them do only get used as occasional vehicles.

The way to deal with this kind of problem is by using preventative measures such as more regular riding or at least running the engine a little each day.

The Valkyrie uses 6 carburetors working together in perfect harmony, most of the time but it too suffers from “idling sickness.”

There are some riders who report that the jets get gummed up very badly when it’s left, say, idling over a winter.

The Goldwing actually tends to suffer mostly from problems after being cleaned.

It’s quite unique in that the most common carburetor problems are traced back to DIY riders who rebuild and reinstall the carburetor incorrectly after cleaning.

The Foreman ATV sometimes suffers from leaks.

The Foreman is an off-road vehicle and so goes through more ‘rough and tumble’ than the average vehicle. The result can be a suffering carburetor.

The Honda CB has had some issues with stalling and the throttle.

When the air/fuel mix runs too lean, the engine doesn’t get enough power, which leads to sputtering and then sometimes stalling while you’re idling or trying to set off after idling.

What Are The Possible Causes Of A Honda Failing Carburetor?

If your Honda has a failing carburetor, the most likely cause of the issue is gumming and buildup within the unit itself.

Hondas do not like to be left idle, but since many bikes get left unused over the winter months, this can happen.

Another cause is the air/fuel mixture running too lean.

This is what brings about sputtering and stalling.

When the carburetor is poorly maintained it loses the crucial balance of air and fuel that your engine relies upon.

Equally, some models can run too rich, which creates black smoke.

If you notice that your Honda motorcycle is burning through a lot more fuel than usual, then the likely cause is that perhaps the pressure is too low and airflow too fast, which is dragging huge amounts of fuel into the combustion process.

The excess is being wasted.

Finally, a cause of failing carburetors in Honda is human error.

Those who remove the carburetor for cleaning but then restore it incorrectly or attempt to modify it before restoring it but botch the job can cause many problems in the carburetor.

What Are The Possible Solutions Of A Honda Failing Carburetor?

Most problems in the Honda carburetor can be solved by carefully detaching it, cleaning its individual components with WD40 and compressed air, and then restoring it correctly.

Carburetors are durable and lasting parts of the motorcycle, but they are sensitive to a lack of maintenance and care.

Therefore, regular cleaning and quick responses to symptoms of problems should ensure that the carburetor doesn’t fail.

Proper cleaning will ensure that any gumming or other buildup is effectively dealt with.

If you experience the air/fuel mix running either too lean or too rich, then the jets need to be cleaned out and possibly replaced.

If you’re getting uneven pressure and airflow, then this kind of problem might persist until it starts causing damage in other parts of the engine.

Finally, a great solution to the problem of human error is to leave certain tasks to professional Honda technicians.

They have the important know-how and experience to ensure that a carburetor is cleaned, repaired, and rebuilt properly.

Can A Honda Motorcycle Run With A Failing Carburetor?

Technically, a Honda could still continue running with a failing carburetor, but it would be operating on borrowed time.

Furthermore, the normally powerful and dependable Honda engine would be struggling and without the power it needs.

The carburetor is crucial, so if it has already failed, then your bike won’t work.

If it is struggling or on the way to failure, then it needs immediate attention.

Does Cleaning The Honda Carburetor Prevent Failing?

The vast majority of problems with the Honda carburetor can indeed be prevented and solved by proper cleaning.

Of course, cleaning can’t manage everything, but it covers the majority of issues.

If an individual screw or other component is broken or otherwise physically damaged, then cleaning won’t help, but what cleaning does do is restore balance to the jets and shafts, allowing properly balanced airflow.

That balanced airflow brings better performance.

Can I Clean It Myself?

You can indeed clean it yourself, but with Honda models, great care should be taken about restoring the carburetor after cleaning.

Mistakes in reinstallation can cause other unwanted problems down the road.

Can I Use WD40 To Clean It?

Yes, WD40 and compressed air together are two of the best tools to clean the carburetor.

WD40 is specifically designed for this kind of application.

Can I Clean It Without Removing It?

Yes, and in fact, this is the best policy if you are worried about not being able to rebuild or restore the carburetor correctly after cleaning is finished.

If you can position the bike correctly, and have enough space and light to clean the carburetor without removing it, then that’s a good course of action.