Everyone’s been there. You’ve seen a great bike at a show or online, and you know your destiny is to build something like it. You can see yourself hammering down the street on it. It turns heads. People compliment your showroom-quality attention to detail.
You’ve scoured the Internet and found scores of photos you love. Maybe you’ve even narrowed down the make and model of your desired donor bike. But how do you transform a factory stock bike into that custom two-wheeled icon?
There are a lot of soft and hard skills you need to build a custom bike. Let's look at some of those below. The good news is you can learn these skills while having fun, and most of them are covered in this handbook.
You can do it, just treat it like a long-term path with a lot of learning along the way. Time to get started.
Most people are comfortable with search engines and can find answers to most of their questions. However, some sources are more useful than others. If you are sold on your donor bike’s make and model, a dedicated forum for that model is the best source of specific information. They’re not hard to find.
Other references to look for include specific sites that focus on your favorite motorcycle style, whether it’s chopper, bobber, cafe racer, brat or tracker. These resources will give you ideas for that style common changes to achieve the look. Add your favorite custom motorcycle website for a great portfolio of inspiration and knowledge.
Your research might extend from general topics like how an engine works to specific tasks like how to disassemble and repair the top end of a 1973 Honda CL350 motor. An hour invested in research before you start a job might save you five hours later.
Get comfortable asking questions on forums and to friends, mechanics, and professionals. It might feel you are asking a lot of silly questions. However, you must ask these basic questions to peel back the layers of understanding to uncover other questions as your knowledge base grows.
Project planning and management
Planning and structuring your work will reap rewards throughout the project, saving time and money (and possibly your sanity). You might initially think you don’t have project management experience, but you’ve surely learned the basics just getting your life organized at work and around the house.
If you compliment this inherent skill with a few free tools and the methodologies described in this book, you’ll soon have the knowledge that is required to get the build done efficiently and with less risk.
Beauty is in the eye of the beholder, but of course some bikes objectively look better than others. Those with design skills can sketch out their bike and get the proportions just right. The rest must rely on photos of bikes to make our own assessment of what looks right. There are many methods to achieve this that don’t involve drawing.
You need to create a detailed image of your project bike’s final form. Without it, the outcome is left to luck and chance, and perhaps you won’t get the bike you imagined. The earlier you lock down the design, the better it will turn out because you will have a clear objective when deciding which changes to make.
Technical drawing might sound odd among the other skills required to build a custom motorcycle. But if you plan to modify and fabricate parts for your bike, the ability to design and draw them before making irreversible cuts in expensive materials is very useful. Regardless of the medium and tools you use, it's helpful to understand how to read and construct technical drawings.
Mechanical and engineering
Working on a motorcycle means you’ll get intimate with a variety of hand tools. Wrenches, screwdrivers, pliers, and a crate full of other tools will become your best friends. You’ll need to collect a basic set of tools or fill in the gaps of your collection if you have some already. But arming yourself is only half the battle—you’ll need to employ proper usage and safety techniques to avoid potential damage done to your bike or yourself.
If you’re working on American motorcycles, imperial-sized wrenches and sockets are typically more compatible. For Japanese and European bikes, metric-sized tools are a safer bet. However, there may be exceptions and specialty tools that you’ll need to find and acquire for your specific make and model.
Mechanical skills should also include an understanding of how the mechanical systems on your bike work. Or at least improving your understanding so you know your pistons from your conrods and your spark plugs from your condensers.
People seem intimidated by electrical systems on their motorcycles. But the electrical system in many cases is no more complicated than carburetors, for example. With enough skill and an understanding of some overall concepts, you can easily tackle electrical systems, especially on older motorcycles.
Once you have a handle on the basic concepts of electricity and the purpose of the components of your bike’s electrical system, you’ll have a basis from which you can further research topics specific to your bike.
There are many of references and books available on automotive wiring, so you can dig as deep as you wish. Most of the forums will also have useful threads that can help you answer questions and learn about the specific electrical system on your ride.
Depending on the work you need to do on the electrical system, the tools, and consumables (wire, connectors, heat shrink etc.) will vary. For example, a cheap digital multimeter for taking voltage measurement is more than enough for occasional use while working on motorcycles. With some judicious choices for other tools and supplies, you’ll be well on your way to mastery of your motorcycle’s electrical systems.
Metallurgy is, among other things, the “technology of metals”. Familiarizing yourself with basic metals and their fundamental properties helps to correctly select a metal for a particular application. When you are customizing a motorcycle, you end up working with metals in some manner.
Considering this is a complete branch of science and engineering by itself, you’ll need to learn enough to make a good decision about metals use on your motorcycle. It's important that you learn about these properties, what they mean for various metals and uses and when and where they should be applied to your bike.
Metalworking and fabrication
If you are building a custom bike with aftermarket bolt-on parts, there is a chance you finish your build without ever picking up a scribe, hacksaw, or file. But if you need (or want) to make a custom number plate bracket, relocate your speedometer, build an aluminum fairing, or chop your frame, you’ll need to get familiar with metalworking.
Metalwork with hand tools can be very satisfying. You take a sheet or chunk of metal, and cut, file, sand and finish a completely custom, one-off part that nobody else has. Then you can drill holes in your part. Tap threads into it. And bolt, screw or rivet pieces multiple pieces together to form more complex assemblies. This is where you can let your creativity shine.
The art of metal shaping combines the additional steps of “shrinking” and “stretching” metal to form complex curves. Fenders and tanks are made by using these additional processes. Metal shaping is simultaneously an art and a science that takes practice and patience. It is beyond the scope of the typical novice builder and therefore, it is not covered in this book.
When you want to step it up, you can start making more radical changes to your bike with welding skills. For motorbike work, we recommended the TIG (Tungsten Inert Gas) welding method, or more correctly GTAW (Gas Tungsten Arc Welding). TIG welding allows you to weld all the common metals used on a custom motorcycle project with one welding machine and one bottle of shielding gas.
Welding is a skill requiring professional study and practice, but you can pick up enough knowledge for simple welding jobs on your motorcycle.
Sometimes you need just the right part to fit a unique application and you know there is no way to buy it from the retail market. Maybe you’re adapting a different front wheel to your project bike and need custom bushings to fit your frame, or you want a bracket to help install rear sets that don’t match your frame.
In these cases, there is often no way of proceeding unless you can access a lathe and a milling machine. Few novice builders will have access to this equipment, and the rest will have to find an engineering shop prepared to make their parts (obviously at some cost). For this reason, it is not covered in this book.
Used lathes and milling machines are available at reasonable prices, however the tooling that is required with each can easily double or triple that cost.
Almost every customized bike project is going to need paint, powder coating, or polishing to deliver a satisfactory outcome, let alone a showroom quality finish. Preparing surfaces for these finishing techniques is essential if you plan to paint or polish yourself, or if you want to save some money not paying a paint or powder coat shop to do this for you.
Your project bike might be suffering the effects of age and neglect, with caked-on dirt, oil leaks, corrosion, scratches, and chipped paint. All these issues are easily addressed with knowledge and elbow grease. And if you are aiming for a show-class finish, its essential to prepare all your surfaces meticulously for the final finish.
There are lots of tools, tips, and techniques you can apply to both speed up surface preparation and achieve impressive results in your own workshop.
Painting and polishing
Once your bike parts have been stripped, cleaned, welded, sanded, and otherwise modified, it's time for the final finish and reassembly. Its surprising how much can be achieved in the home workshop with aerosol cans of paint or a basic compressor and sprayer set-up.
Would a professional painter in a spray booth achieve a better finish? Yes, of course. But you can easily learn enough to achieve a sense of satisfaction on your own and control the cost of your project build in the process.
Polishing is similar. Mirror finishes can be achieved on steel and aluminum in your own workshop using a systematic process in your workshop.