What To Know Before Rebuilding A Classic Honda Motorcycle Engine

Rebuilding a classic Honda motorcycle engine can be a fun and educational experience. Not only does it allow you to get your hands dirty with an exciting DIY project, but it can also help you save money — by avoiding the costs of professional labor — and develop new and valuable skills. But while rebuilding your own classic motorcycle engine can be an incredible adventure, it also comes with its share of challenges. However, there are several things you should know before you tear apart your engine.

As is the case with many DIY projects and hobbies, one of the most essential things you can do is ensure that you have the proper tools before you start. Following that, you'll need to have a solid knowledge foundation before you rip your bike apart. That's especially true if your project is a classic model, as older components may be more expensive and difficult to find, and you'll want to minimize your risks of damaging essential parts. But that's not all you need to know. 

There are various other considerations to make before you start your rebuild, including figuring out where you'll buy your new parts, determining whether you'll need a professional's help, and understanding the true scope of your project. That said, let's go ahead and dive deeper into each of these considerations.

One of the first and most critical steps you can take before starting a motorcycle engine rebuild is to ensure that you have the correct tools for the job. It's never fun to progress several hours into a project only to realize you need a special tool, and it's even worse if that tool is hard to find or only available online. Gathering all of the necessary tools before you begin is the smartest move, allowing you to start your project confidently. There will always be unforeseen snags and obstacles when working on an engine rebuild — be it a car, motorcycle, tractor, or something else entirely. But that doesn't mean you shouldn't prepare for what you can anticipate. That means researching and determining what tools you'll need before starting. 

You should thoroughly research your bike's model before tearing its engine apart. Doing so will help you learn about the necessary tools and help prepare you to complete the job. However, if you want to build a general tool collection first, the most common devices you may need include a ratchet and socket set, a motorcycle lift, an impact wrench, a torque wrench, and an oil drain pan. You'll likely need various other tools, like pliers, wrenches, screwdrivers, and even diagnostic or electrical equipment. However, purchasing these essential tools is a great start, and it can put you on the right path toward completing your engine rebuild with minimal issues.

We mentioned above how important it is to research your bike's model to determine what tools you'll need. However, determining which tools you'll need is only one of the reasons you need to do some research before starting an engine rebuild. Learning about your classic Honda's internal workings is also an excellent way to prepare yourself to tear the engine apart and rebuild it. Learning on the fly is one way to go, but preparing yourself beforehand is much smarter and may help you avoid unnecessary problems or mistakes. All that said, how exactly do you learn about your bike and its internal parts, especially if it's a classic model?

You can search online if you want, and you may be able to find some helpful forum posts or YouTube videos. However, there are many classic underrated Honda motorcycles, and a limited amount of information may be available online. Instead, one of the smartest things you can do is purchase a repair manual or maintenance guide specific to your bike. These books are typically filled with valuable information exclusive to individual makes and models. They tend to include information like repair and replacement processes, torque specifications, and fluid capacities. This is vital knowledge to have when rebuilding an engine, especially if you're not a seasoned mechanic or professional repair technician.

Another essential consideration before you start rebuilding your classic Honda motorcycle engine is that you may struggle to find some of the needed parts. This is more applicable to extremely rare Honda motorcycles, like the Motocompo and the Dream CB50R. If you own one of Honda's most famous motorcycles, like a Rebel or Gold Wing, you'll probably have an easier time sourcing parts. Before you begin your rebuild, you should start looking around and exploring your options when it comes to replacement components. Several online stores stock classic Honda motorcycle parts. However, it's vital that you do your due diligence to determine whether the seller is reputable and if the parts you order will actually fit your bike. 

Many people recommend shopping for classic automotive and motorcycle parts on eBay. While it can be a solid resource, you should exercise caution. Remember that basically anyone can sell on eBay, and it's crucial that you research the seller's ratings and reviews before making a purchase. More specialized stores, like Common Motor Collective and Charlie's Place, may also be worth checking out. These stores concentrate on vintage motorcycle parts and have solid reviews from the bike community. 

Wherever you buy your parts, remember that you may have to wait a while for them to arrive. Plan ahead of time when preparing for an engine rebuild, and start looking for parts before you begin to minimize your bike's downtime.

When you get ready to rebuild your classic Honda motorcycle engine, you'll probably have a few expenses in mind. Tools and replacement parts are some of the most prominent expenditures you'll have to face, but they may not be the only costs you have. You should keep in mind that you may have additional expenses in the form of machine shop fees or any professional help that you require. Why might you need a pro's help? 

Well, after tearing your engine apart and rebuilding it, you'll have to put it back together again. If the motor is extremely old or has seen heavy use, it may need more than just new internal parts. Its skeleton may also need some love in the form of machining and cylinder boring. Machining an engine block, cylinders, and pistons helps remove carbon scoring and ensures that mating surfaces are even. It also helps the pistons move smoothly through the cylinders and contributes to proper sealing between components.

It's impossible to be certain whether you'll face these extra costs, as you often don't realize you need a machine shop's services until you've torn the motor apart. However, it is wise to plan for the worst. Budget for these expenses, even if you don't think your engine needs them. Then, if your motor requires any machining work, your wallet won't be taken by surprise.

So far, we've covered individual things you need to consider before embarking on a classic Honda engine rebuild project. All of those factors are important, but it's also essential that you understand the big picture. Rebuilding a motorcycle engine is a huge commitment. It's going to take a lot of time and energy, and it will probably cost a fair amount of money, too. You should understand this going in, and you should be prepared to deal with obstacles and unexpected expenses. 

You should also remember that your skill level will play a prominent role in how quickly and efficiently you're able to complete the project. If it's your first time doing DIY work on your bike, you should expect a slow and tedious process. If you're a seasoned motorcycle veteran or a professional mechanic, you'll probably struggle a lot less.

That said, don't get discouraged, even if you're a complete novice. Rebuilding an engine is challenging no matter your skill level, and even though it's difficult, it's a fantastic way to learn more about your bike and develop some great skills. Remember to take your time and remain patient. Rebuilding your classic Honda motorcycle engine may not be the smoothest or easiest process in the world, but it's sure to be rewarding in more ways than one.