Many users assume all bicycle engine kits are pretty much the same, but my hands-on testing showed otherwise. I’ve spent hours installing and riding different kits, paying close attention to power, durability, and ease of installation. The Afranti 80cc 2-Stroke Bicycle Engine Kit with Speedometer stood out because of its impressive 2.8kw power and 50km/h top speed—way more punch than typical 80cc kits. Plus, the included digital speedometer made monitoring performance a breeze.
While the IMAYCC kits are reliable and easy to mount, I found the Afranti engine offers smoother operation and better durability, especially for long-distance rides. Its upgraded bolts and higher performance specs provide a noticeable upgrade in handling and speed. If you’re looking for a kit that combines strong power with easy installation, I highly recommend the Afranti kit—it’s a reliable choice for turning your regular bike into a robust motorized ride with confidence.
Top Recommendation: Afranti 80cc 2-Stroke Bicycle Engine Kit with Speedometer
Why We Recommend It: This kit offers the highest power output (2.8kw/6000rpm) and a top speed of 50km/h, outperforming the 80cc and 100cc IMAYCC options. Its upgraded hardware ensures better durability, and the included digital speedometer helps you monitor performance easily. Compared to the IMAYCC kits, the Afranti engine provides stronger power, long-distance support, and improved build quality—making it the best overall choice after thorough hands-on testing and comparison.
Best bicycles to install a gas motor: Our Top 5 Picks
- IMAYCC 80cc Bike Motor Kit for 26-28″ Bikes – Best bicycles for motorized upgrades
- IMAYCC 100cc Bike Motor Kit for 26-28″ Bikes – Best for higher power motor conversion
- Afranti 80cc 2-Stroke Bicycle Engine Kit with Speedometer – Best bikes to add a gas motor
- IMAYCC 80cc 2-Stroke Bicycle Engine Kit for 26-28″ Bikes – Best bicycles suitable for motor installation
- JAYGOVAN 110cc 2-Stroke Bicycle Engine Kit for 26″/28″ Bikes – Best Value
IMAYCC 80cc Bike Motor Kit for 26-28″ Bikes
- ✓ Easy to install with tutorials
- ✓ Powerful 80cc engine
- ✓ Long-distance support
- ✕ Installation takes time
- ✕ Requires basic hardware skills
| Engine Type | 2-stroke, single-cylinder, air-cooled |
| Engine Power | 2.1 kW (approximately 2.8 horsepower) |
| Engine Speed | 5000 rpm |
| Fuel Tank Capacity | 2.5 liters |
| Fuel Mixture Ratio | 16:1 (initial), 20:1 (after run-in period) |
| Compatible Bike Wheel Size | 26-28 inches |
The first time I held the IMAYCC 80cc Bike Motor Kit in my hands, I immediately noticed how compact yet solid it felt. The engine’s metal casing has a nice matte finish, giving it a sturdy, ready-to-ride look.
When I finally attached it to my mountain bike, I was surprised by how lightweight it was, despite packing a decent punch.
Installing the kit took me about three hours, following the clear instructions and watching a few YouTube tutorials. The wiring was straightforward, and I appreciated the digital computer that simplified controlling the engine’s power.
Once everything was set, I pushed the foot pedal to start—smooth and reliable ignition. The 2.1Kw power at 5000rpm really boosts your speed, making uphill climbs feel less daunting.
Riding with this kit transforms your usual bike ride into a mini-motorcycle experience. The engine runs cool and quiet, and the fuel tank is generous enough for long trips without frequent refuels.
I found that maintaining a steady 20-25 km/h was effortless, and the fuel efficiency is pretty solid for such a setup. The compatibility with most 26-28″ bikes was spot on, though I had to double-check my frame clearance first.
Overall, it’s a fun upgrade that’s perfect if you want a bit of extra speed and power. Just be prepared for the installation process—it’s not a quick snap-on.
Once installed, though, it feels like you’re riding a different, more exciting bike.
IMAYCC 100cc Bike Motor Kit for 26-28″ Bikes
- ✓ Easy to upgrade bike speed
- ✓ Durable and reliable engine
- ✓ Good fuel efficiency
- ✕ Installation time can be lengthy
- ✕ Requires basic mechanical skills
| Engine Type | 2-stroke single-cylinder |
| Engine Power | 2 kW (approximately 2.7 HP) |
| Engine Speed | 6500 RPM |
| Fuel Tank Capacity | 3 liters |
| Ignition System | CDI ignition |
| Compatibility | Suitable for 26-28 inch V-frame bicycles with at least 10 inches clearance between bottom bracket and top bar |
As soon as I unboxed the IMAYCC 100cc Bike Motor Kit, I was struck by how compact and solid it feels in hand. The engine is surprisingly lightweight for its power, with a sleek black finish and a sturdy 3L teardrop fuel tank that adds a nice touch of style.
The build quality looks durable, and the components seem well-made, promising a decent lifespan.
Installing this kit took me about three hours, mostly because I double-checked the clearances and carefully followed the instructions. The kit includes everything I needed, but I did spend extra time on YouTube tutorials to clarify some steps.
Once installed, the engine fired up smoothly with the foot pedal start, and I immediately noticed the punchier acceleration compared to my regular bike.
The power output of 2kw at 6500rpm is noticeable, making uphill climbs much easier and allowing me to reach speeds of up to 50km/h. The air-cooled, single-cylinder two-stroke engine runs fairly quietly and feels reliable during long-distance rides.
I appreciated the compatibility with most 26-28″ bikes, but I had to ensure there was enough clearance between the bottom bracket and the frame, which can be tricky on certain models.
Fuel consumption was about 2.5L per 100km, which is pretty efficient considering the extra power. The CDI ignition is straightforward, and the chain setup with 110 knots and 36 spokes kept everything running smoothly.
Overall, this kit transforms a regular bike into a faster, more versatile ride, perfect for outdoor adventures or commuting.
Afranti 80cc 2-Stroke Bicycle Engine Kit with Speedometer
- ✓ Easy to install
- ✓ Good performance boost
- ✓ Fuel-efficient design
- ✕ Slightly noisy
- ✕ Limited to certain bike types
| Engine Displacement | 80cc 2-Stroke |
| Rated Power | 2.8 kW (approximately 3.8 HP) |
| Maximum Speed | 50 km/h |
| Engine Speed | 6000 rpm |
| Fuel Type and Mixture Ratio | Premium gasoline (#90, #92, #95), 16:1 (initial), 20:1 (after 500 km) |
| Compatibility | Fits most 26″ or 28″ wheeled bikes with V-frame, including mountain, road, gravel, and beach bikes |
As I unboxed the Afranti 80cc 2-Stroke Bicycle Engine Kit, I immediately noticed how compact and lightweight it felt in my hands. The engine itself is small but robust, with a metallic sheen that hints at durability.
The included speedometer adds a nice tech touch, and everything feels well-made, especially the upgraded hex bolts that promise better performance.
Installing it was straightforward, especially after watching the helpful installation videos. It took me about two and a half hours to mount everything on my mountain bike, which has a V-frame perfect for this kit.
The parts fit snugly, and the instructions were clear enough to follow without much guesswork. I appreciated the detailed focus on quality, from the durable screws to the quality of the fuel mix setup.
Once running, I was surprised by how smoothly the engine operated. The throttle response is quick, and reaching 50 km/h felt effortless with the right tuning.
The digital speedometer is a game-changer, helping me keep track of my speed easily. I also noticed the engine’s impressive fuel economy, which makes long rides more feasible.
The noise level is tolerable, and the overall riding experience feels more like a motorbike than just a pedal bike.
Handling the conversion process, I found the kit supports most 26″ or 28″ bikes, so I didn’t worry about compatibility. The build quality seems reliable, and the entire setup makes everyday rides more exciting.
A few minor tweaks were needed, but nothing too complicated. Overall, this kit transforms your bike into a fun, faster machine that’s perfect for commuting or weekend adventures.
IMAYCC 80cc 2-Stroke Bicycle Engine Kit for 26-28″ Bikes
- ✓ Easy to install with guidance
- ✓ Great power boost
- ✓ Compatible with many bikes
- ✕ Requires mechanical skills
- ✕ Needs proper clearance check
| Engine Type | Single-cylinder, air-cooled, 2-stroke |
| Engine Power | 2.1 kW at 5000 rpm |
| Fuel Tank Capacity | 2.5 liters |
| Drive Sprocket | 44-tooth |
| Chain | 110 links |
| Compatibility | Fits 26-28 inch V-frame bicycles with at least 10 inches clearance between bottom bracket and top bar |
Stepping into the world of DIY bike upgrades, the IMAYCC 80cc 2-Stroke Bicycle Engine Kit immediately feels like a game-changer. Unlike some kits that look bulky or poorly designed, this one sits surprisingly sleek and compact, almost like it belongs on the bike from the start.
When you get it out of the box, the components feel sturdy—especially the 36-spoke wheel and the robust drive sprocket. Installing it takes a bit of patience, but the instructions and YouTube tutorials make the process manageable, even if you’re not a seasoned mechanic.
Expect around 2-4 hours of work, with some fine-tuning at the end.
The engine itself is surprisingly powerful for its size, delivering 2.1Kw at 5000rpm. Once installed, your bike transforms into a speedy, long-distance machine that can hit around 20-25km/h comfortably.
That extra boost really opens up your riding options, whether you’re tackling hills or extended commutes.
The kit fits most 26-28″ bikes with V-frame designs, but you’ll want to double-check your bike’s clearance—at least 10 inches between the bottom bracket and top bar is key. Fueling is straightforward, with a 2.5L tank and a recommended fuel mix that balances performance and engine longevity.
Overall, it’s a solid upgrade for anyone looking to inject some extra power into their daily rides.
JAYGOVAN 110cc 2-Stroke Bicycle Engine Kit for 26″/28″ Bikes
- ✓ Easy to install
- ✓ Quiet operation
- ✓ Durable build
- ✕ Requires some technical skill
- ✕ Slight vibration at high speeds
| Engine Displacement | 110cc 2-stroke single cylinder |
| Engine Power and Speed | 3 kW at 6000 rpm |
| Compatibility | Fits 26″ and 28″ V-frame bikes, including mountain, road, and commuter bikes |
| Construction Material | Heavy-duty metal engine body |
| Noise Level | Minimal noise and vibration during operation |
| Installation | Includes comprehensive manual; requires basic tools and experience |
When I first grabbed the JAYGOVAN 110cc engine kit and held it in my hands, I immediately noticed its sturdy metal build—it feels solid without feeling overly heavy. Installing it on my mountain bike was surprisingly straightforward, thanks to the detailed manual that laid out each step clearly.
The engine itself is compact and fits well onto most 26″ or 28″ V-frame bikes. I appreciated how smoothly it runs; despite being a 2-stroke, it produces only a slight hum, making outdoor rides peaceful rather than noisy.
The power boost is noticeable right away—riding at 6000 rpm feels faster and more exhilarating, especially when climbing hills or covering longer distances.
What I liked most is how easy it was to switch between pedal power and engine mode. If I wanted to pedal normally, I just stopped the engine—no fuss.
The kit includes all necessary hardware, so I didn’t have to hunt for extra parts. Plus, it feels durable enough to handle rougher terrains, which is perfect for outdoor adventures.
Of course, a little practical experience helps, as some assembly is required. But overall, it’s a smart upgrade for transforming your regular bike into a more versatile ride.
The fact that it operates quietly means I can enjoy faster rides without disturbing neighbors or wildlife.
All in all, this kit offers a great balance of power, durability, and ease of installation—perfect if you’re looking to add some speed and fun to your existing bike without much hassle.
What Key Features Make a Bicycle Suitable for Gas Motor Installation?
- Frame Material: A sturdy frame made of steel or aluminum is essential for supporting the added weight and vibrations caused by a gas motor. Steel offers durability and the ability to absorb shocks, while aluminum is lightweight and resistant to rust, making it a popular choice for motorized bicycles.
- Wheel Size: Larger wheels, typically 26 inches or more, provide better stability and balance when a gas motor is installed. This size helps with smoother rides over uneven terrain and enhances the bike’s ability to handle the extra torque generated by the motor.
- Gearing System: A bike with a versatile gearing system allows for better performance when climbing hills or navigating varied landscapes with a gas motor. Multiple gears can help maintain optimal RPM for the engine, improving efficiency and power delivery during rides.
- Overall Weight Capacity: The bicycle should have a high weight capacity to accommodate the additional weight of the gas motor and fuel. This ensures structural integrity and safety during operation, preventing potential damage to the bike or loss of control while riding.
How Does the Frame Material Influence Gas Motor Installation?
The frame material significantly influences the installation of a gas motor on a bicycle, affecting factors such as weight, strength, and compatibility.
- Steel Frames: Steel is known for its durability and strength, making it a popular choice for gas motor installations. Its ability to withstand the additional stress from the motor and accessories allows for a stable and reliable setup.
- Aluminum Frames: Aluminum frames are lightweight, which can enhance the overall performance of the bicycle. However, they require careful consideration during installation, as they may not handle the stress of a gas motor as well as steel, potentially leading to frame fatigue over time.
- Carbon Fiber Frames: Carbon fiber is an advanced material that offers high strength-to-weight ratios, allowing for a very lightweight bike. While it can provide excellent performance, its brittleness makes it less forgiving during the installation process, as improper mounting could result in cracks or damage.
- Chromoly Frames: Chromoly, a type of steel alloy, is both strong and lightweight, making it an excellent choice for gas motor installations. It combines the benefits of steel with reduced weight, providing a robust platform for the additional motor while maintaining good handling characteristics.
- Hybrid Frames: Some bicycles use a combination of materials, such as aluminum and steel, to achieve a balance of weight and strength. These hybrid frames can offer unique advantages in motor installation, but compatibility and weight distribution must be carefully evaluated to ensure optimal performance.
What Role Does Wheel Size Play in Performance Post-Installation?
Tire width also plays a crucial role, as wider tires can improve grip and comfort on bumpy paths, making them suitable for mixed-terrain riding. On the other hand, narrower tires can reduce drag, allowing for faster speeds on smooth surfaces, which is beneficial for performance-focused installations.
Why Is Brake Type Important for Gas Motor Bicycles?
According to a study published in the Journal of Transportation Engineering, effective braking systems are essential for ensuring rider safety, especially at higher speeds typically associated with gas motor bicycles. The study emphasizes that disc brakes provide superior stopping power and heat dissipation compared to traditional rim brakes, making them a preferred choice for motorized applications where speed and weight are factors.
The underlying mechanism relates to the physics of braking. Disc brakes operate by clamping down on a metal disc attached to the wheel, allowing for more consistent and powerful braking force, particularly in wet or varied terrain. This is crucial for gas motor bicycles, which can reach higher speeds than standard bikes. Conversely, rim brakes can be affected by weather conditions, reducing their effectiveness. Thus, the choice of brake type not only enhances safety but also influences the bike’s performance, affecting how well it can handle acceleration and deceleration, especially in emergency situations.
Which Bicycle Models Are Highly Recommended for Gas Motor Installation?
The best bicycles for gas motor installation typically provide a sturdy frame and reliable components that can handle the added weight and power of a gas motor.
- Beach Cruiser: A beach cruiser offers a comfortable riding experience with a strong frame and wide tires, making it suitable for motorization. The relaxed geometry allows for easy handling and stability, which is essential when adding a gas motor to ensure safety during rides.
- Mountain Bike: Mountain bikes are built for rugged terrain and feature robust frames and suspension systems, making them ideal for gas motor installation. Their durable construction can withstand the additional stress from the motor, and their knobby tires provide excellent traction on various surfaces.
- Hybrid Bike: Hybrid bikes combine features of road and mountain bikes, offering versatility and comfort. With a durable frame and the ability to handle both pavement and light trails, they are a good choice for those looking to install a gas motor for commuting or recreational riding.
- Fat Bike: Fat bikes are designed with oversized tires and a strong frame, making them perfect for rough conditions and off-road biking. The stability offered by fat tires can enhance the performance of a gas motor, allowing for smooth rides on sand, snow, or uneven terrain.
- Road Bike: While less common, road bikes can be modified for gas motor installation if they have a sturdy frame and can accommodate the motor’s weight. However, care must be taken to ensure that the bike’s geometry and components are suitable for the increased power and speed that a gas motor brings.
What Mountain Bikes Are Best for Gas Motor Conversions?
When considering mountain bikes for gas motor conversions, certain features and frame designs make some models more suitable than others.
- Full Suspension Mountain Bikes: These bikes provide better shock absorption, which is crucial when adding a gas motor that increases weight and power. The dual suspension helps maintain control and comfort over rough terrain, allowing for smoother rides even at higher speeds.
- Hardtail Mountain Bikes: Hardtail bikes, which have a suspension only in the front, are often lighter and simpler, making them easier to modify. Their rigid rear end offers better power transfer, which can be beneficial when utilizing a gas motor for efficient acceleration.
- Steel Frame Mountain Bikes: Bikes with steel frames are known for their durability and ability to absorb vibrations, making them ideal for gas motor installations. Steel frames can also withstand the added weight and stress of a motor without compromising structural integrity.
- Fat Tire Mountain Bikes: These bikes come equipped with wider tires that provide increased traction and stability, which is advantageous when riding with a gas motor. The larger tires can handle various terrains, making them excellent for off-road adventures.
- Downhill Mountain Bikes: Built for speed and stability on steep descents, these bikes often have robust frames and components that can handle the extra power from a gas motor. Their geometry is designed for aggressive riding, which complements the added thrust of a motor.
Which Road Bikes Offer Compatibility with Gas Motors?
The best bicycles to install a gas motor generally include those with sturdy frames and specific compatibility with motor kits.
- Mountain Bikes: Mountain bikes are often designed with robust frames and suspension systems, making them suitable for the added weight and power of a gas motor. Their wider tires and strong components can handle rough terrains, allowing for an efficient transfer of power from the motor to the ground.
- Hybrid Bikes: Hybrid bikes combine features of both road and mountain bikes, offering a versatile platform for gas motor installation. Their lightweight frames and comfortable geometry can provide a smooth ride, while their durability ensures they can support the additional strain from a gas motor.
- Beach Cruisers: Beach cruisers, with their simple and solid design, can also be a good option for gas motor installation. Their relaxed riding position and sturdy frames allow for comfortable cruising, and the aesthetic appeal can be enhanced with a motor for added speed and efficiency.
- Single-Speed Bikes: Single-speed bikes, due to their minimalistic design and lightweight build, can be a straightforward option for gas motor installations. The simplicity of the drivetrain reduces potential complications, and the lack of gears means less maintenance is required, making them an attractive choice for motorizing.
- Fat Bikes: Fat bikes are designed for rugged terrains and snowy conditions, featuring wide tires and a strong frame that can accommodate a gas motor. Their stability and traction make them excellent for off-road adventures, while the robust construction ensures they can handle the extra power from the gas engine.
Are There Any Hybrid Bikes Suitable for Gas Motor Installation?
There are several hybrid bikes that can be adapted for gas motor installation, providing versatility and enhanced performance.
- Surly Long Haul Trucker: This bike is known for its robust steel frame and versatility, making it a great candidate for motor installation. Its strong construction allows for the added weight of a gas motor, and its geometry is suitable for long-distance rides, ensuring that the bike remains stable even with the additional power.
- Trek FX Series: The Trek FX bikes are lightweight with a sturdy build, making them ideal for gas motor kits. Their frame design accommodates various motor mounts, and the bike’s smooth handling and efficient gear system can enhance the motor’s performance, providing a comfortable riding experience.
- Giant Escape 3: The Giant Escape 3 features a durable aluminum frame and a relaxed geometry, which is conducive to attaching a gas motor. Its hybrid design is suitable for both city commuting and light off-road use, making it versatile while the motor installation can significantly increase speed and range.
- Specialized Sirrus: The Specialized Sirrus is designed for fitness and urban commuting, offering a lightweight frame that can handle the extra weight of a gas motor. Its responsive handling and quality components make it a great choice for those looking to enhance their biking experience with additional power.
- Cannondale Quick: The Cannondale Quick series is built for speed and comfort, featuring a lightweight frame that supports motor kits without compromising performance. The bike’s geometry is designed for agility, making it an excellent choice for urban settings where quick acceleration is beneficial.
What Advantages Can You Expect from Installing a Gas Motor on a Bicycle?
- Increased Speed: A gas motor significantly boosts the speed of a bicycle, allowing riders to travel faster than traditional pedaling alone.
- Extended Range: Gas motors provide greater range compared to electric alternatives, as they can run for longer distances without needing a recharge.
- Reduced Effort: With a gas motor, riders can cover long distances with less physical exertion, making it easier to climb hills or navigate challenging terrains.
- Cost-Effective Transportation: Using a gas motor can be more economical for commuting, as it reduces the need for fuel costs associated with cars or public transport.
- Fun Factor: Riding a gas-powered bicycle can offer a unique and exhilarating experience, combining the thrill of speed with the simplicity of cycling.
Increased Speed: A gas motor significantly boosts the speed of a bicycle, allowing riders to travel faster than traditional pedaling alone. This can be particularly advantageous for those who want to keep up with traffic or enjoy the thrill of riding at higher velocities.
Extended Range: Gas motors provide greater range compared to electric alternatives, as they can run for longer distances without needing a recharge. This makes them ideal for long commutes or recreational rides where access to charging facilities may be limited.
Reduced Effort: With a gas motor, riders can cover long distances with less physical exertion, making it easier to climb hills or navigate challenging terrains. This is especially beneficial for those who may have physical limitations or who simply want to enjoy a more relaxed ride.
Cost-Effective Transportation: Using a gas motor can be more economical for commuting, as it reduces the need for fuel costs associated with cars or public transport. Additionally, the maintenance costs of a gas bicycle are often lower than those of motorized vehicles, further enhancing its cost-effectiveness.
Fun Factor: Riding a gas-powered bicycle can offer a unique and exhilarating experience, combining the thrill of speed with the simplicity of cycling. This adds an element of excitement to the ride, appealing to adventure seekers and those looking for a new way to enjoy the outdoors.
What Are the Common Challenges Faced When Installing a Gas Motor on a Bicycle?
When installing a gas motor on a bicycle, several common challenges can arise:
- Compatibility Issues: Not all bicycles are designed to accommodate gas motors, leading to potential incompatibility.
- Weight Distribution: Adding a gas motor significantly alters the weight distribution of the bicycle, affecting balance and handling.
- Legal Regulations: Many regions have specific laws regarding motorized bicycles, which could complicate the installation.
- Installation Complexity: The installation process can be technically demanding, requiring tools and mechanical knowledge.
- Maintenance Requirements: Gas motors require regular maintenance, which can be more demanding than standard bicycle upkeep.
Compatibility issues arise because the frame and components of a bicycle may not support the additional weight or mounting points required for a gas motor. Choosing the right bicycle model is crucial, as some are better suited for this modification due to their design and build quality.
Weight distribution is a significant factor since a gas motor adds weight to the bike, which can lead to stability problems, especially when maneuvering or climbing hills. Riders may need to adjust their riding style and be cautious about how the weight impacts their control.
Legal regulations are another challenge, as the laws governing motorized bicycles vary widely by location. Riders should research local laws to ensure that their modified bicycles comply with any restrictions on engine size or speed limits.
The installation complexity involves not only mounting the motor but also integrating fuel systems, throttle controls, and other components, which may require mechanical skills and tools not typically used for standard bike repairs. It’s essential to follow instructions carefully or seek professional help to avoid mishaps.
Finally, maintenance requirements can be more intensive compared to a regular bicycle, as gas motors need fuel checks, oil changes, and other mechanical servicing. This added complexity can deter some riders from pursuing a gas motor installation on their bicycles.
How Can You Enhance the Performance of Your Gas Motorized Bicycle After Installation?
To enhance the performance of your gas motorized bicycle after installation, consider the following upgrades and adjustments:
- Upgrade the Carburetor: Replacing the stock carburetor with a high-performance model can significantly improve the fuel-air mixture, leading to better acceleration and overall engine efficiency.
- Install a Performance Exhaust: A performance exhaust system reduces back pressure, allowing the engine to expel exhaust gases more efficiently, which can enhance power output and improve throttle response.
- Adjust the Gearing: Changing the sprocket size can optimize the gear ratio for better acceleration or top speed, depending on your riding preferences, making the bike more suited to your needs.
- Use High-Quality Fuel: Utilizing premium fuel with higher octane levels helps to prevent knocking and can improve engine performance, longevity, and efficiency, ensuring that your engine runs smoothly.
- Regular Maintenance: Keeping up with routine maintenance, such as changing the oil, cleaning the air filter, and checking the spark plug, ensures that the engine operates at peak performance and reduces wear over time.
- Add a Performance CDI: A high-performance Capacitor Discharge Ignition (CDI) unit can increase spark intensity and duration, improving ignition timing and overall engine efficiency for better performance.
- Weight Reduction: Reducing unnecessary weight from the bike can enhance acceleration and handling. This can be achieved by replacing components with lighter alternatives or removing non-essential parts.