KDX Freebie Project

So not long ago I was lucky enough to find a motorcycle. For free. This, is it’s story.

The 1980 Kawasaki KDX. 175cc’s of vintage, 2-stroke thumping glory

I was helping my sister and brother in law move on the weekend of April 28th I believe. Afterwards, we decided to get some dinner. It was then that I saw it. Sitting by some mailboxes. I told my brother-in-law to pull over in case it was curbed…not having much faith that someone would just give that away.

We turned around and stopped. I asked a woman by her apartment if she new anything about it. She didn’t. I walked down a long driveway of apartments to see if I could find some clues. It was then that I saw a guy in his garage that was littered with motorcycles. I had a feeling I found the person I was looking for…

I talked to him for only about a minute. The conversation went a lot like:

Me: Are you giving this away?

His name was Brett.

Brett: Yeah, we have a lot of projects and I can’t get it into gear. If you put a vise-grip on the shift lever you should be able to drive it. The carburetor is in the box with it. The engine ran fine when I last drove it.

Me: So I can have it?

Brett: Yeah, I don’t want it. It’s yours.

So I took it! And there were a box of parts/components with it as well. I walked it back to my sister and brother-in-laws and then we got dinner.

Admittedly, I was like “4-year-old-with-face-covered-in-chocolate” excited about it. Ironically, when I was in high-school, I gave away a dirtbike for the exact same reason. It was stuck in gear and I didn’t want to take on the project. So in some cosmic sense, I feel like the universe gave me back my bike…and said…”fix this damn thing. It’s your destiny.”

So I decided I would. I pushed the thing back to my place. It was a nice three-mile haul. I parked it behind my apartment for a night so I could formulate my plan for it. However, I knew I had to come up with a better idea because it was not very secure in a parking lot.

It was then that I had the brilliant idea that I could just work on it in my apartment. It took a couple running starts but I got it up the steps. Not saying this to fan my pride…I live in a single bed apt. so there was no other place to work on it. As they say, out of necessity, comes pushing heavy objects up steps.

So I had it in my apartment for diagnostics. It did not even have the carburetor installed (the part that fuels the engine). It had compression though (good sign). It took me a couple days of internet research, looking at it, deciding what to do, before I could muster up the courage to start taking it apart. It was one of those moments where I knew that as soon as I started tearing it down, it may never get back together…

How to figure it out

Side note – You may be wondering, where do you even start on a project like this? I have never owned a motorcycle besides the high school one, and I never even touched that one. So how do you learn as you go? Well…I’m glad you asked.

Step 1. Buy a manual. I got a factory service manual on the electronic-bay for $8.

Step 2. Someone posted on Youtube exactly what you’re trying to do. I guarantee it.

Step 3. Find exploded diagrams online of the components you’re taking off/putting back together. There are diagrams for almost everything. If you look hard enough you should be able to find something. E.g. cmsnl.com sells parts for the bike, but I just used the site to see exploded views of the components. When you can see everything blown apart, it’s easier to see that motorcycles are really just glorified 3D puzzles that you can rip up the streets with after you’re done. See below.

Step 4. Have basic hand tools. I took the thing apart with basic hand tools that I already had. Try not to invest too heavily in new tools and only buy what you need.

Step 5. Find a forum. Trust me, someone out there WAY nerdier than you made a whole website dedicated to exactly what you are fixing. Connect with your people, and they will guide you. For this project, there is www.kdxrider.net. Whether you have a car, truck, computer, clogged ketchup bottle, anything, there’s a forum for it, trust me. A guy on a forum showed me a video he made so I knew what year it was.

Diagnostics and Teardown

At this point, I knew that the main issue with the bike was that the shifting shaft was broken, at least. I knew this because the shifting shaft splines were very mangled. That made it impossible to use the gear-shifter for it’s intended purpose.

Depending on how you look at it, this is either a simple fix or not a simple fix. For me it was relatively challenging. For a more seasoned bike mechanic this is probably one of the more simple jobs.

The first step was to get the engine off the bike. In retrospect this step probably wasn’t necessary, but it made it easier for me. Unfortunately I did not take that many pictures of that process. It was fairly straightforward though. If you scroll up and down really fast it can look like the engine just popped off.

Before I got my grubby mits on it.
After I got my grubby mits on it. #diningroomgarage

Finding the offending component(s)

After the engine was out, I could take the crank-case cover and inspect to see if there was any other damage inside the transmission. First, I had to take the clutch off. That’s the big round thing in this picture.

With clutch
Without clutch

As you can see, things look pretty shiny and not broken, which is a good sign. This picture already has the shift shaft taken out. The dead part is below.

I found the part # by using the parts diagram on cmsnl.com.

Funny thing about 1980 KDX 175 shift shafts…people really want top dollar for them on eBay…since it’s a pretty rare component, it cost about $100 after shipping to get a brand new OEM part. This is a NOS (new old stock) part.

After making the most reasonable offer I could on eBay, I settled for the price of $100.

Putting it All Back Together

So now that I got my new part, I installed it and could start re-assembling the bike.

Only one other unknown remained. I was nicht-so-sure about the carburetor. So I watched this YouTube where someone explained how carburetors work in a delightful Hindi accent. It is not about the specific bike I was working on, but the same basic principles apply. Gas goes into it, it mixes with air, becomes all atom-y, and then engine goes boom.

So I cleaned out the carburetor as best I could, and installed it on the bike. They tend to clog with old gasoline that turns to a gummy material.

This came with the bike.
You see that giant, gaping hole? That’s where the carb is supposed to go

I installed the carb and re-assembled the rest of the bike.

Fueling Up, and Using Some Old Indian Tricks

Since it’s a two-stroke, I got some 2-stroke oil to put in the gasoline. After spilling a lot of fuel out of the no-spill container, I was ready for the moment of truth.

Will it run!?

Oh hell yes it will. I sprayed some starter fluid (the trick) in the air intake and it fired right up!

Smoke means it works. Frankenstein lives.

Additionally, the shift shaft was the only issue with the gear shifting, so I took it for a spin. It shifted through all the gears just fine.

Sew much fun

Part of the joy of something like this is the risk of becoming road kill. In the middle ages, brick-layers had to stand under the bridges they build as the key stone was put in place. If there work was crap, they would just let the bridge fall on them and crush them. I think that’s a good way to live life. If you don’t trust your own work, who’s can you?!

Is it worth it?

Some hobbies cost money. If you play things right, you can get your hobbies to pay you. I kept tabs on the amount of $$ I spent on the bike, as well as rough guesses on the time I spent.

Overall I spent $260 on a free bike in parts, gaskets, oils, and tools I needed. I ended up selling it soon after for several reasons. Kind’ve wish I would’ve kept it, but you can’t turn back time…I sold it for $423. Which doesn’t seem like much, but hey craigslisters weren’t biting at the $600-800 range. In perfect shape I’d say this bike is worth $1300 so just use that for perspective.

However, I did A: make money B: learn a lot C: feel more prepared to own another motorcycle.

It wasn’t really all about turning a profit, but I don’t want to make money pits for myself either. There are a lot of people who will just sink cash into projects like this and it’s not worth it I’d say.


I hope you enjoyed reading about his build/repair as much as I liked doing it. If you ever get a chance to get an enduro…I highly recommend it. They are good fun. And remember, don’t be safe!

Here’s a thump video:

Side notes/Resources:

This guy was a big inspiration for me. Down-to-earth guy and his wife make trashed bikes work…he has a big following. He did a similar project on an old Kawasaki.

Jennie’s Garage

I also drew some inspiration from this book:

Full Open Source Motorcycle:

Someone developed a motorcycle that can be sourced completely by local machine shops. It can be made fully street legal. I found this project before I found the bike. It is entirely different, but is still a really cool idea.


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