I finally had it! My first big bore 1000cc+ motorcycle. Sure I noticed it had a few things rigged here and there, but I could ride it home and I could probably fix it up fine! That night after removing the tank and airbox, I started panicking as I noticed problem after problem with this bike. I decided to take it out on a short little ride and suddenly heard a clack clack clack BANG as the bike threw itself out of gear and revved up into a false neutral. What have I gotten myself into?

The loud bang I heard, I learned was the symptom of a bent shift fork. A mortal problem for a motorcycle in which to repair, the engine normally must be removed from the frame and nearly completely disassembled. Not a common job for a novice mechanic and a very costly one to be done by a shop. Well, I was $2000 in the hole on this bike and if I was ever going to get any of my money back out of it, I had to dig in and fix this thing. That night, my friend came over and we began removing the engine from the frame. It was surprisingly lightweight as we lifted the engine up and strapped it to my garage workbench.

I found a service manual online and started getting my hands greasy. It was A LOT of work to do. Once I split the crankshaft case apart, I found the issue. Sure enough, it was a bent shift fork. Not one but two of them. You can tell which are bad because when they bend, they start wearing circular grooves into the arm section which results in a sort of "smiley face" type of witness mark. I found some used parts on eBay and bought them. Swapping them out was not that fun, but after a lot of hours, the engine was finally back in one piece.

So with the engine back together mostly, I decided, well since it is out of the frame I might as well upgrade some parts. I read online that the ZX11 ninja uses the same engine and therefore the camshafts and valve springs could be swapped out. Cool, I bought some on eBay and used my air compressor to keep the valves seated while I swapped out springs.

Since I had new cams, I had to re-jet the carburetors. And since I was re-jetting I might as well rebuild them.... This project started snowballing. I then ditched the stock airbox for pod filters. Well if the engine is going to breath better with cams and carb mods, I might as well upgrade the exhaust system....

So headers for this bike are hard to find. But I found a Yoshimira header on eBay for a GPZ1100. A different bike that used the same engine. You can see the difference in the exhaust routing of the new header verses the old one that is straight. Since the exit was different, I had to build a pipe that could connect the new header to the old exhaust muffler which was a Kerker brand can. I used pieces of 2.5" pipe that I cut into pie slices to carefully link the two pieces together. After paint, I was happy with the result and it sounded AMAZING!

The final upgrade to the bike was a set of sprockets. 1 gear smaller on the front and two gears larger on the rear. Finally I synchronized the carburetors using a special home made tool. A board with sections of tubing linked together and to the carburetor. The tubes are filled with automatic transmission fluid and when the intake of each cylinder fights for air, they pull on the fluid in different ways allowing you to tune the carburetors to pull at an equal rate. The result is a very smooth running engine.

When I got done with the bike, I'm not going to lie. It was too much for me. The bike would easily pull the front wheel up in the air in 2nd gear with just a light snap of the throttle. It was more than a bit scary to ride. But at the same time it ran soooo well. I decided not long after this repair/build, that I wanted to change gears and live life in an RV for a while to finally see the country. For that reason, I ended up selling the bike. I got almost what I put into it money wise which made me happy enough since broken bikes are worth just a fraction. I learned a great deal from this project tech wise, and most importantly, I learned to be VERY careful about buying used motorcycles. Sometimes just paying a little bit more can save you a lot of headache and dollars in the long run. Duly noted.