3 Reasons Why Used FCR Carburetors Can Be Used

3 Reasons Why Used FCR Carburetors Can Be Used

I'll start with the conclusion.

"Often, it's okay to purchase a used FCR that you find in an auction. However, there are occasional duds."

Whether this is true or false is up to you to decide. In this blog post, I'll explain three reasons why it's okay to buy a used FCR. But remember, it’s all at your own risk. If the used FCR you buy turns out to be a dud, you'll just have to accept it. Please purchase at your own risk.

Back around 2010, used FCRs were considered disposable and not worth purchasing. The reason was due to a structural flaw in the FCR: wear on the body. The roller of the slide valve directly contacts the body, so with long-term use, the body wears out. When the body wears down, the slide valve no longer returns smoothly. This was the reason why buying a used FCR was a bad idea. Even an overhaul couldn’t fix it. Since the FCR body cannot be replaced, once it’s worn out, the FCR is no longer usable.

However, as of 2023, there are three solutions available:

1. Big Roller Kit (easily available)
2. SEP Bearing Guide (sold in very limited quantities in Japan)
3. Carburetor Parts Kit for FCR - KEYSTAR
All of these products can address the issue when the body is worn. Products 2 and 3 also have a preventive aspect. You can find more details about these products through web searches. I recommend checking out blog posts written by those who have already explored these solutions.

Now, I’ll detail the three reasons why it’s okay to purchase a used FCR. After this, you'll surely enjoy checking out auctions even more. So, let’s get started!

Once an FCR has been in someone else’s hands, it is considered a used FCR.

Any FCR that has been mounted once is considered a used FCR. No matter how clean it looks, whether it has been polished with sandpaper or soaked in carburetor cleaner, the history of the carburetor remains unknown. There is no end to doubts.

In this blog post, the theme is to approach buying used FCRs with hope. One can only pray that there are as few replacement parts as possible. It is assumed that parts used regularly are not replaced, and the policy is to replace only parts that seem problematic.

Many used FCRs from abandoned vehicles are also listed in auctions. There are quite a few that can be used immediately with just cleaning or a simple overhaul. FCRs that came from abandoned vehicles are particularly promising if they are available in the market.

Reason 1: Solutions for Body Wear Are Available

As mentioned earlier, a significant reason is that solutions for the FCR's critical weakness, which is body wear, are available for purchase. Body wear can be assessed through visual inspection and a light disassembly. Based on my experience, excessive wear is rarely encountered. In cases of touring use with frequent stop-and-go traffic, there may be instances where the throttle opening around 1/2 is abnormally worn.

For addressing this issue, you can use the following available solutions:
1. Big Roller Kit
2. SEP Bearing Guide
3. Carburetor Parts Kit for FCR - KEYSTAR

Please use the option that is most accessible in your region.

Reason 2: Many FCRs Are in Good Condition, and Parts Replacement Is Easy

Although this is completely subjective, many FCRs available at auctions appear to be in good condition. The term "overhaul" is commonly used in the motorcycle industry. While a complete overhaul may seem daunting, the FCR is a racing part and is designed to be disassembled with relative ease. It is simple to replace gaskets and O-rings, and doing so can sometimes restore the FCR to good working condition.

Most issues with FCRs stem from long-term neglect. Problems such as gasoline turning into gum or metal parts rusting are common causes of poor performance. Removing rust and cleaning out the gum-like gasoline often results in the FCR working properly again. Some FCRs are even listed in a condition where they work just by being mounted.

High-quality used FCRs may be priced higher. However, the FCR is designed to be disassembled, and while disassembly and cleaning are not necessarily simple, they are generally an extension of normal maintenance. It may take some time, but disassembly and cleaning should be possible. Gaskets and other replacement parts are usually inexpensive.

Note: There are non-disassemblable parts as well. Details will be provided later.

Reason 3: Affordable Repair Parts Are Easily Available

As of 2023, it is uncertain how the FCR landscape will change in the next five years. Carburetors have a global fanbase, but they are considered relics of the past. Nowadays, affordable repair parts can be easily purchased online. Genuine parts are available from Keihin as well.

Since the widespread adoption of smartphones around 2010, there is now more information and a greater availability of repair parts. Taiwanese-made FCRs are also on the market now. While their precision is unknown, the increased availability of repair parts reflects the growing resources for maintaining these carburetors.

An FCR with non-disassemblable parts that are defective is considered a dud.

While I mention that it's a dud, it doesn’t mean that it’s unusable. However, it does require extra effort. Identifying the cause of performance issues can be time-consuming.

FCRs have non-disassemblable parts that can be problematic. These parts are fixed with liquid gasket and often painted over with bolts. If these non-disassemblable parts are defective, it can be quite troublesome. Issues such as gasoline clogging or damaged gaskets can be particularly challenging to address. Additionally, since these parts are non-disassemblable, checking them immediately is difficult.

Using carburetor cleaners, which are intended to be used with the engine running, can often cause damage to the gaskets inside. Carburetor cleaners are designed to be drawn into the engine while it’s running and are not suitable for cleaning rubber or plastic parts. Please be cautious.

Is it cheaper to overhaul a used FCR yourself?

The cost of overhauling a used FCR yourself is generally lower. This applies only if you do the overhaul yourself. You will need to purchase repair parts.

Among the repair parts, the most expensive ones are:

Vacuum release plate
Parts for addressing body wear
Other parts are not extremely expensive. Users who regularly tune FCRs should know what is necessary. In such cases, it is fine to order individual parts and perform the overhaul.

If you want to purchase a complete set of repair parts, it is recommended to use the Carburetor Parts Kit for FCR - KEYSTAR.

For FCR Beginners: Debut with a Used Racing Carburetor!

If you're considering purchasing a used FCR on auction and debuting with a racing carburetor, you might be apprehensive if you haven't worked with FCRs before. However, if you're already familiar with motorcycle maintenance, overhauling an FCR should be manageable. Installing an FCR can be a bit cumbersome, but enjoy the process and achievement.

The next step is starting the engine. If you’ve never done tuning before, starting the engine after installing the FCR might make you anxious. Used FCRs can come with issues, and you'll need to take time to check and address them one by one. If you’re starting from scratch, it can be mentally challenging. Even if the engine starts successfully, issues like unstable idling can make it hard to determine whether the problem lies with the FCR, the tuning, or issues with the jets. Most of the time, tuning problems are to blame, but it can be quite stressful for beginners. You might end up asking someone for help or reverting to the previous carburetor.

It's important to first determine if the issue is with the installation or the carburetor itself. For those with no experience, it’s helpful to build a network on social media where you can ask questions. This can help prevent difficulties down the road.

For my next motorcycle, I plan to use a used FCR by overhauling it. For those familiar with the process, it’s not a difficult task or judgment. If starting with an FCR on a non-running motorcycle, you’ll need to consider the engine's condition as well. Replacing the carburetor on a running motorcycle is relatively straightforward. With effort, even beginners should be able to succeed.

If you're a beginner overhauling an FCR, using the Carburetor Parts Kit - KEYSTAR is recommended. Depending on the condition, there’s no need to rush to replace the slide valves with new ones.

3 Reasons Why Used FCR Carburetors Can Be Used【summary】

I believe that purchasing a used FCR from an auction generally results in fewer bad deals. Even considering the cost of overhaul parts, it's usually cheaper than buying new. The time spent may be seen as a drawback, but if you enjoy spending time on such tasks, it's worth it.

For users who are familiar with FCRs, buying a used one shouldn't be too much of a concern. However, for those who have never worked with them before, it can be a daunting task. The risk of uncertainty is something to consider when opting for a lower price instead of relying on a custom shop.

Professional overhaul services are often not as cost-effective. I've covered various aspects of used FCRs. I hope you all have a great FCR experience! See you again!

Photo Gallery

I have picked and posted photos from the past logs of when I disassembled the FCR. You can find more in other articles, so feel free to explore the FCR category or use the site search from the menu to look for more information.