There are plenty of upgrades and modifications you can make to increase motorcycle performance. While most people opt for upgrading their tyres, engines, or brakes, the motorcycle frame can play a significant role in improving their riding experience.
Improving the design of your motorcycle frame can improve its stability, potentially reduce weight for better fuel efficiency and speed, and enhance handling. You can do this by optimising the motorcycle’s frame or opting for a custom motorcycle frame.
When upgrading a motorcycle’s frame, the key areas for optimising are improving the bike’s geometry, suspension, and materials. For example, moving to lightweight materials, increasing the rake angle, adjusting the trail, and aftermarket engine mounts to reduce vibrations.
With the right design and alignment, it’s possible to improve stability and handling to the point that a bike feels like a new one.
Aftermarket Frame Modification Options
When looking to upgrade your motorcycle’s frame, along with custom modifications, there are aftermarket frame modifications available depending on your make and model. Aftermarket frames are popular for increasing performance for racing. They can also be used to change your bike’s look or replace a damaged stock frame.
The specific aftermarket frame modifications will depend on your bike’s make and model. Some models get more aftermarket support because they’re more popular. Below, we’ve listed the common different types of custom bike options available when modifying frames.
Bobber
These types of frame modifications used to be called the “bob-job” until the last two decades or so. This frame modification focuses on customising a bike’s frame to resemble racing motorcycles from the old American Class C racing days. The main goal of this modification is to strip down any excess weight on the bike, improving the power-to-weight ratio.
Cafe Racer
Cafe racer-modified frames were a trend in the 1950s and are still popular today. Like the bobber, the frame would be stripped to optimise the power-to-weight ratio, and the engine optimised for maximum output. Custom cafe racer frames are built for speed, not comfort, and are meant for short-distance rides.
Chopper
Chopper-type frame modifications originated in the US and are still extremely popular there. They’re easily recognisable, as they’re custom motorcycle frames with extremely extended forks for the front wheel. As much as they are a fun way to modify your bike, they’re also a form of art expression.
Scrambler
Scramblers are making a huge comeback, with manufacturers releasing bikes with stock scrambler frames, like the Ducati Scrambler and BMW R-nine-T. Scrambler-type frames feature a vintage look with knobby tyres suitable for off-road riding. Scramblers were popular back in the day when specific dirt bikes weren’t widely available, so riders would modify their bikes for rough terrain.
Streetfighter
The streetfighter frame seems to be an offshoot of the cafe racer. It evolved in the late 1970s and early 1980s in Japan for Japanese street bikes. It involves stripping as much fairing away as possible, including removing mirrors and foot pegs, to get a more aggressive look and increase performance. It also typically adds a large headlamp.
Supermoto
Bikes with a custom supermoto-styled frame are designed for when racers are competing on multiple types of terrain, like circuit (road racing), packed dirt (track racing), and irregular jumps or obstacles (motocross). If you’re a racer, this is a great option; however, it is not as practical for daily use.
Drag Bike
Drag bikes have their frames modified to suit drag race conditions and get the most out of their engine. Since they only ride in straight lines, there isn’t much focus on handling, just power and performance. If you’re a competitive drag racer, this is the type of frame and build you’ll want to go for, but it isn’t suitable for daily riding.
Rat bike
If you’re a fan of Mad Max, then rat bikes are for you. Motorcycle customisation, especially for frames, can get expensive. However, rat bikes aim to use as little money as possible while still keeping the bike functional, and rust is a plus. In most cases, rat bikes also equip modifications not made for their bike model but attach it anyway—giving it a unique, distinct look.
The above-listed types of custom bikes are just for inspiration. Nowadays, when it comes to modifying bike frames, almost anything is possible—even if you can’t find an aftermarket kit for the frame modification you want, it’s possible to fabricate custom parts at a workshop.
Tips For Motorcycle Frame Design
Designing a motorcycle’s frame requires a deep understanding of mechanics, how a motorcycle functions, and engineering principles. Below, we’ve listed tips for designing a motorcycle frame and the factors to consider.
- It’s important to consider the material used for the design. Common materials for motorcycle frames include steel, aluminium, and carbon fibre. The right one for your frame will depend on your goals, e.g. durability or speed.
- When designing a frame, it’s important to ensure its weight is evenly distributed and can withstand heavy stress, especially in key areas like the headstock and suspension points.
- It’s critical to consider the motorcycle frame’s geometry. Poor geometry can lead to rider discomfort, poor stability, and bad handling.
- If you want optimal traction and handling, you should try to balance the front-to-rear weight.
- If you’re looking to decrease weight on the frame for more speed, it’s important to ensure there is still enough room to hold the engine, battery, electronics, and other motorcycle components.
- To streamline maintenance, ensure easy access points in the frame to reach components, like making it easier to reach the engine and check fluids.
- If you’re designing the frame yourself, always get a professional mechanic experienced in custom bike builds to look over and evaluate your designs.
- If you want to optimise your frame’s shock absorption and increase your comfort when riding, consider the position of the suspension mounting points when designing the frame.
- Prototype and test the custom frame in real-world conditions and adjust the design as needed.
Ensuring The Motorcycle Stability
Ensuring motorcycle stability on a custom frame, especially one made from custom-manufactured parts, is critical for the riding experience and safety. Always get a professional to check and test the design in real-world scenarios and ensure everything is properly balanced.
For instance, when it comes to frame geometry, you’ll want to ensure your motorcycle’s rake, trail, and wheelbase are correctly balanced. If they aren’t, it can impact your motorcycle’s stability and performance.
When designing the frame, remember that a low centre of gravity is important for any heavy components—like the engine and fuel tank. Keeping them as low as possible gives you a lower centre of gravity, improving stability, especially when braking or cornering.
It’s critical to ensure the weight is evenly distributed between the front and rear wheels. An imbalance is a safety risk and will severely impact your motorcycle’s stability when riding. It will also affect acceleration and braking.
The last thing you want is a shoddy job when fitting custom frame parts or putting together a custom frame. Make sure that all welding and fabrication are high-quality and from a professional shop. Poor welds or misaligned components can lead to instability.
Custom Motorcycle Build & Modifications at Taverner Motorsports
If you’re looking to do a custom motorcycle build, including modifying the frame, contact the Taverner Motorsports team. We offer custom motorcycle modification options for most motorcycle models—with a passion for British and Harley-Davidson motorcycles.
Our team has over 40 years of experience in the motorcycle industry, performing routine services, fabricating custom parts, and assisting with custom motorcycle builds. We only use the highest-quality materials and fabrication methods to ensure that all the custom motorcycle parts we craft are long-lasting and durable.
When you come to us to fabricate parts or make aftermarket modifications, you can expect transparency from start to finish. Our team will be upfront regarding manufacturing and installation costs and give you a timeline for completion—updating you every step of the way.
If you’re looking to bring your motorcycle to the next level with custom frame modifications, get in touch with us today with your ideas and request a quote. The Taverner Motorsports team would love to hear from you and help you create your dream ride.