Creating a custom trike rear end can be an exciting and rewarding project for enthusiasts looking for a custom trike build. By understanding key components like the rear axle, differential, independent rear suspension, brakes, and drivetrain, you can design and fabricate a trike motorcycle rear to match your riding needs.
Salvaging parts from donor motorcycles, ATVs, and autos provides a cost-effective starting point. But crafting a rear end from scratch allows for the ultimate customization – selecting the perfect diff, drive, and swing arm setup to produce neck-snapping acceleration and optimized handling.
In our guide, you can learn more about building an entire rear axle assembly for a VW Trike or Harley Trike as much is the same apart from the power plants, even if you thought it would be different. For fun and enjoyment, you’ll better understand how to build and drive a trike at highway speeds. (Read 2001 Jeep Grand Cherokee Security System Reset)
What is a Trike Rear End?
The back portion of a three-wheeled motorbike known as the “trike rear end” houses the rear axle, differential, suspension, brakes, and driving components.
Building a unique trike rear can be exciting for trike fans wishing to modify or convert their bike into a trike. The following are the main elements of a trike’s rear end:
- Rear Axle – The axle that connects the two rear wheels. This can be a solid axle or use independent suspension.
- Differential – Splits engine power between the two rear wheels while allowing them to spin at different speeds for cornering.
- Suspension – Shock absorbers and swing arms allow the wheels to move up and down over bumps.
- Disc Brake – Disk brakes on each rear wheel provide stopping power.
- Drive System – The chain, belt, or shaft connects the engine to the rear differential.
Many builders start with a rear end from a donor motorcycle, ATV, or even auto and customize it to their needs. However, building a trike rear end completely from scratch is also possible.
Where Do You Get Parts to Build a Trike Rear?
You need to find components such axles, differentials, wheels, brakes, drive shafts, and suspension pieces while constructing a trike rear end.
Here are a few possibilities:
- Donor vehicles – A cheap source for complete rear ends are old motorcycles, ATVs, VWs, and rear-wheel drive cars/trucks. You may need to modify components to fit your trike.
- Aftermarket parts – Companies like Neale, Roadsmith, and Frankenstein Trikes sell trike-specific rear-end kits and parts for DIY builds. Get money OFF|Xuankun Four parts.
- Custom fabrication – For a truly unique rear end, have parts like axle shafts, swing arms, and drive shafts custom-made by a machine shop.
- Salvage yards – You can find deals on used rear ends, differentials, motorbike brakes, wheel hub, and suspension components at auto and motorcycle salvage yards.
How Do You Build the Rear Axle for a Trike?
The rear axle ties the whole trike rear end together. Here are some axle options:
- A solid rear axle is simple and durable. You’ll need to weld or connect the axle permanently to the rear wheels and differential.
- An independent suspension rear uses two axle shafts, allowing the wheels to move independently for better handling.
- Axle sleeves allow adjusting rear track width by sliding the wheels in or out along the axle. Useful for trike stability.
- Axle diameter, length, offset, and stubs must be spec’ed based on your going to build. Custom machining may be required to get these right.
- Consider axle material – steel is strong but heavy, and aluminum is lighter but weaker. Chrome-moly and stainless steel also have benefits.
Building a safe, robust rear axle is critical – take measurements and plan the design carefully! (Read Can A Gas Stove Explode)
What Type of Rear End is Best For a Trike?
Choosing a rear-end setup involves tradeoffs in complexity, performance, and cost:
- Basic solid axle drive designs are simple and inexpensive but sacrifice handling and ride quality.
- Independent suspension systems improve handling but are more complex to build.
- Using a car/truck rear differential tends to be sturdier but heavier than a bike unit.
- Two-speed differentials add lower gearing for hill climbing at the cost of more complexity.
- A limited slip diff stops one wheel spinning so power can be evenly spread across both wheels, like in racing or sprint cars when cornering or starting.
- Shaft drive output is excellent for low maintenance, but shaft output requires precision fabrication at a precise right angle to the other rear drive components.
- Chain drive or belt drive unit gives more flexibility in layout but needs adjustment and maintenance.
- Airbag vs. coil vs. leaf spring suspension offer different rides. Consider swing arm vs trailing arm.
Also think about tire size, ground clearance, rake, how the rear attaches to the main trike frame, and how the engine will pull the rear frame. Test ride other trikes to get a feel for what will work best for your needs and riding style.
What is the Best Differential for a Trike Rear End?
The differential transfers power from the engine to the two rear wheels, allowing them to turn at different speeds. Here are the top options:
- Motorcycle differentials are lightweight but may not handle high power. Yamaha, Honda, and Harley units are popular.
- VW differentials are durable and can be easily flipped for trike use.
- Aftermarket differentials from Quaife, Neale, and others offer limited slip and better power handling.
- Welding the spider gears can create a simple “locked” diff for drag racing trikes.
- Ring gear reduction inside the diff housing provides extra low-end torque. Many use a common 2:1 reduction gear ratio.
- Built-in sprocket mounts on the diff simplify drive chain routing.
Consider how much power your engine will produce when selecting a diff. Pinion bearings are also vital for durability under load. (Learn How To Thaw Underground Water Pipes)
What is the Best Way to Build Rear Suspension for a Trike?
Good rear suspension improves comfort and handling. Two main approaches are:
- Swing arm suspension uses pivoting arms and shocks for each wheel. It allows wider tire clearance and is more adjustable.
- Trailing arm suspension locates the wheel on a pivoting arm trailing the frame. It is compact and straightforward but less adjustable.
- Airbag, coil over, or leaf spring shocks give different rides. Air is the most adjustable, but coils may handle hard cornering better.
- Longer swing arms increase stability but reduce responsiveness. Shorter arms feel more nimble.
- Independent suspension allows each wheel to react separately. It improves handling but is more complex.
- Rake, anti-squat, tire size, and ground clearance affect handling. Test different setups to tune the ride.
Good suspension takes experimentation. Seek help from experienced trike builders if tackling this part of the project for the first time.
How Do You Pick Rear Brakes for a Trike?
With two rear wheels to stop, braking power is critical. Look for:
- Motorcycle calipers offer lightweight power. Larger 4-piston units bite harder than 2-piston calipers.
- Big brake rotors (320 mm+) provide maximum stopping power. They disperse heat better and resist fading.
- Steel braided brake lines avoid flex and give a firm, responsive pedal.
- Quality brake pads suited to the rotor material (organic, ceramic, semi-metallic, etc).
- Linked brakes balance force between both wheels. Custom linkages may be needed.
- Parking brake on at least one wheel for safety. A mechanical lever lock or electric brake.
Consider brake bias and systems that distribute force optimally front to rear. Larger rear rotors can help balance braking versus the front wheel.
Conclusion
Building a custom trike rear end is an involved but fulfilling project. The back end ties the entire trike together and is critical to good handling and riding. Take the time to research and source quality donor components before deciding on the rear design.
Fabricate mounts and brackets carefully with an eye to strength and adjustability. Lastly, don’t rush the assembly – test fit and tack parts before final welding to get alignments and clearances right. Patience and fabrication skills will be rewarded with a rear end you can enjoy riding for years! (Read Can You Run Ethernet Cable Through Air Duct)
FAQs
What is the best donor motorcycle to use for a trike conversion?
Some good donor bike options are Harley Davidson Touring models, Honda Goldwings, BMW K-series, and Yamaha Ventures. You want a heavier cruiser with good frame rigidity and engine power.
Is it hard to get a trike endorsed on your motorcycle license?
Endorsing a trike is usually straightforward. In most states, you must bring the completed trike to the DMV for a VIN inspection. Some states may require a motorcycle license test.
Can you build a reverse trike with two wheels at the front?
Yes, it is possible to build a reverse trike. The fabrication and engineering are more complex. Weight balance needs more consideration without a third rear wheel.
