The Incredible Millyard Kawasaki Z1 1600 V8 Motorcycle

Table of Contents:

1. Introduction
2. Cutting and modifying the crankcase
3. Welding the crankcase
4. Fitting additional connecting rods
5. Making new big end roller cages
6. Assembling the crankshaft
7. Machining the crankshaft bearings
8. Modifying the frame to fit the engine
9. Wiring and Ignition timing
10. Completing the engine and painting the frame
11. Modifying the carburetors
12. Final touches and test ride
13. Conclusion

Introduction

In this video, I will take You through the process of how I made the engine for my Kawasaki Z1 1600 V8 back in 2001. Starting from cutting and modifying the crankcase to fitting additional connecting rods and assembling the crankshaft, I will guide you through each step of the process. Along the way, I will also discuss the challenges I faced and the solutions I came up with. So, let's get started and dive into the fascinating world of engine modification!

Cutting and Modifying the Crankcase

The first step in creating the V8 engine was to obtain an old set of Kawasaki Z1 crankcases. Using a handsaw, I cut the top crankcase in half to remove the gearbox section. The next challenge was to lean back the rear bank of cylinders without the bottom of the barrel hitting the primary drive gear. This was done by filing metal from the bottom of the upper crankcase until it leaned back just the right amount. Then, I notched the front of the crankcases to fit the front cylinders.

Welding the Crankcase

Once the crankcases were modified, I prepared them for welding. After vapor blasting and completing the first stage of welding, I had to reposition the starter motor to accommodate the leaned-back rear bank of cylinders. I extended the crankcase by 10 millimeters and created new holes to mount the existing standard generator cover. With the welding complete and the crankcases ready, I moved on to the next step in creating the V8 engine.

Fitting Additional Connecting Rods

To fit an extra four connecting rods into the space of a standard crankshaft, I examined the Kawasaki Z1 crankshaft and identified areas where I could shave off metal to gain extra space. I turned down the width of the connecting rods and replaced the roller bearings with thinner ones. I also reduced the thickness of the side thrust washers and flywheel webs. With these modifications, I successfully fit two connecting rods onto each of the four crank pins.

Making New Big End Roller Cages

To accommodate the modified connecting rods, I needed to make new big end roller cages out of 7075 T6 aluminum. By measuring an existing cage and making them slightly narrower, I created four blanks ready for slotting. Using a fixture on my lathe, I machined the slots with radius ends. After trial assembly and achieving a perfect fit, I could proceed to the next step.

Assembling the Crankshaft

Before assembling the crankshaft, I needed to make eight bronze bushes for the little end eyes to reduce the diameter and fit Z650 pistons. With the bushes fitted, I began assembling the crankshaft in my lathe, starting with the inner four cylinders. As the modified components were pressed together, the original positions of the bearings remained intact. After a trial assembly and final adjustments, the v8 crankshaft was finished and ready for further work.

Machining the Crankshaft Bearings

I proceeded to machine the areas in the crankcase where the bearings sit for the crankshaft. This involved redirecting the oil gallery on the underside of the upper crankcase and boring the inner main bearing journals using a custom tool. By HAND scraping and fine-tuning the bearings, I achieved a perfect fit. With the main bearings machined, I could now proceed to the next stage of the engine modification.

Modifying the Frame to Fit the Engine

Fitting the V8 engine into the Kawasaki Z1 frame required extensive modification. I repositioned the lugs on the right-hand points casing to accommodate two top lugs instead of one. This allowed me to retain the original look of the Z1 engine from the right-hand side. I also modified the battery box and relocated the electrical components to clear the rear exhaust manifolds. With the frame modifications complete, I could proceed to refit the engine.

Wiring and Ignition Timing

With the engine securely bolted in the frame, I completed the wiring and performed the ignition timing. Using a dial gauge and a degree disk, I fine-tuned the ignition timing to perfection. This step was crucial to ensure optimal performance and smooth operation of the V8 engine. With the wiring and ignition timing complete, the engine was now ready for the final touches.

Completing the Engine and Painting the Frame

With the engine nearly complete, I decided to give the top crankcase a heat treatment before proceeding further. After five hours in the oven at 230 degrees Celsius, the heavily modified top crankcase was ready for the next steps. I machined the areas where the bearings sit, adjusted the oil gallery, and hand-scraped them to ensure a perfect fit. With the crankcases bolted up tight, the bearings in place, and the bottom crankcase untouched, I applied the finishing touches.

Once the engine and frame modifications were complete, I sent the side panels, rear fin, and petrol tank for painting in Z1A colors. The glossy black frame, along with the freshly painted panels, gave the V8 engine a stunning appearance. Excited to see the final result, I eagerly awaited the return of the painted components.

Modifying the Carburetors

During the creation of the V8 engine, I initially fitted Yamaha CV carburetors. However, tuning them proved to be challenging, so I decided to switch to the standard Z1 carburetors. To fit them, I had to cut them down and convert them from a link lift to a cable lift. By removing the top portion and machining down the throttle slides, I achieved a perfect fit that allowed for smooth operation.

Final Touches and Test Ride

With the modified carburetors fitted, the final touches were made to the V8 engine. I trimmed down the side panels to clear the rear exhaust pipes and ensured that all components fit and worked harmoniously. Finally, I took the bike for a test ride and was thrilled with the immense power and performance of the V8 engine. It was a rewarding moment to see the fruits of my labor in action.

Conclusion

Creating the V8 engine for my Kawasaki Z1 was a challenging and rewarding experience. From cutting and modifying the crankcase to welding, fitting additional connecting rods, and assembling the crankshaft, every step required precision and Attention to Detail. The frame modifications, wiring, and carburetor adjustments added further complexity to the project. However, with perseverance and determination, I successfully completed the engine modification. The end result was a powerful and unique V8 engine that proudly sits on display at the Barber Motorcycle Museum in Birmingham, Alabama.

Highlights:

• Creation of a V8 engine for a Kawasaki Z1
• Cutting and modifying the crankcase
• Welding and repositioning the starter motor
• Fitting additional connecting rods
• Making new big end roller cages
• Assembling the crankshaft
• Machining the crankshaft bearings
• Modifying the frame to fit the engine
• Wiring and ignition timing
• Completing the engine and painting the frame
• Modifying the carburetors
• Final touches and test ride
• Display at the Barber Motorcycle Museum

Frequently Asked Questions (FAQ):

Q: How long did it take to make the V8 engine? A: The process of creating the V8 engine took several months. It involved meticulous planning, cutting and modifying the crankcase, welding, fitting additional connecting rods, and numerous other steps. Each stage required careful attention to detail and fine-tuning to ensure optimal performance.

Q: What were the main challenges faced during the engine modification? A: One of the main challenges was finding the right balance between modifying the crankcase and maintaining the structural integrity of the engine. Ensuring that the modified parts fit perfectly and aligning the connecting rods were also significant challenges. Additionally, repositioning the starter motor and modifying the frame required careful planning and execution.

Q: Was it difficult to adjust the ignition timing and wiring? A: Adjusting the ignition timing and completing the wiring required precision and attention to detail. Using a dial gauge and a degree disk, I fine-tuned the ignition timing to achieve optimal performance. Similarly, relocating the battery and electrical components to clear the rear exhaust manifolds was a challenging task, but essential for the proper functioning of the engine.

Q: How did the V8 engine perform during the test ride? A: The V8 engine delivered impressive power and performance during the test ride. The additional connecting rods and modified crankshaft resulted in enhanced performance and increased displacement. The carefully adjusted carburetors ensured smooth operation and optimal fuel delivery. Overall, the test ride confirmed the success of the engine modification and the satisfaction of achieving the desired outcome.

Q: Where can I see the V8 engine on display? A: The V8 engine is proudly displayed at the Barber Motorcycle Museum in Birmingham, Alabama, USA. If you happen to be in the area, make sure to visit the museum and witness this incredible creation firsthand.