1986 Kawasaki KX80

Cool story. I don't have anything small to compare this bike to, but it does have the oversize cylinder on it, so it's actually a 100cc engine. The bike pulls really well. Its a very snappy feel, as the powerband hits pretty hard, and early. Maybe it's just how this bike is configured though and not typical of this year KX80. I'm looking forward to see how it feel after all new bearings and fixing up a lot of the sloppiness that was in the old parts.

OK back to some build pics... it's been a while and a lot of progress has happened since I last posted.

The rear wheel assembly needed some tweaking to make it go together right. Probably due to a lack of clear information, the spoke holes were just a bit off, you can see in the pic. However the shop that prepped them was very happy to take all the components, adjust, and do a loose lace for me.

While waiting for the rear wheel to be assembled, I moved onto the engine.

First it got a good washing.

The carb on this bike worked great, so I just wanted to give it a good clean up. No other changes were necessary.

Next I pulled the cylinder and took a look at the piston. Decided to go with a new vertex piston



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The rest of the engine tear down is shown here. Luckily there wasn't much that had to be done, so it was pretty much just a preparation for paint after this.

After scuffing up the engine paint, and drying it up, a coating of primer was sprayed on, sanded up and then a top coat of black was applied.

With paint done, engine reassembly can happen.

mud flap!

Kick starter -
Just before the rebuild, we put on a new kick starter lever, and it began cracking, pretty quick, in the same place the old one had broken. So, instead of just buying another that might break as well, I built up the weak area with some weld, ground it down and painted it.

Also painted up was one of the carb clamps, and the shift lever

With the engine installed I could finish up the wiring.

I extend the wires, routed them, and taped up the harness as shown.

The generator cover was cracked, so I trimmed it to at least make a clean edge. Then I cleaned it up and installed it.

We are looking for a good condition replacement cover if anyone knows of one.

Front brake pads arrived and they were the right ones!
This is the 3rd set of brake pads I bought...

Next big milestone was handlebar and front controls.

After doing some searching, we decided to reuse the existing front controls. The brake and throttle are original, but the clutch was not. Still it was more consistent to have them all cleaned up, primed, and painted the same way.

New cables and grips,and kill switch purchased, but I reused the brake line (for now).

were

The exhaust was the next thing to cover. The muffler was easy, just a clean up and high temp paint.

The pipe however was pretty dented and needed some work to make it look good.

I tried a bunch of ways, but it was easiest to just cheat in the end and apply some high temperature epoxy to the dents, wet sand it smooth and paint over it. (putty and paint make it what it ain't). It looks good, but I have no idea how it will hold up if used a lot (or even once). Either way, I can get a new pipe or try something else if this doesn't hold up. As I said, it looks good for now, and I really don't expect this bike to get a lot of use after this anyway.

Also, i first painted the pipe satin, but decided matte was a better look.

Rear wheel assembly came back, so I was able to work on that install.

The bike is now rolling once again.

Well found one weird problem...

The new rear sprocket had a mistake in the machining of it. A few teeth didn't line up. Fortunately, the seller was super helpful and replaced the part as shown in the pics.

Another thing to deal with, the mud flap rubbed against the chain.

I ended up slotting the holes in the flap and shifting it over a bit so everything fit with some healthy clearance.
It is barely noticable

Had to get inventive on the rear brake cable. It wasn't available anywhere, and the original was damaged and beyond a good clean up.

So, I use some swageless wire rope fittings used on wire railings. They are all stainless, and I think it turned out pretty good.

in the first two pics, the original cable shown along with the fittings we purchased.

after doing some homework on forums, I decided to use ATF Type F in the gearbox.

The red oil in the sight glass looks cool.

One of my biggest worries on this job was the plastics. I tried cleaning them up for quite a while, using all types of methods like starting with a razor blade, wet sanding, torching, etc... Nothing made the plastics look clean enough to be on the bike considering how the rest turned out.

So we made the decision to purchase the DC plastics kit for this bike, which luckily exists.

They only didn't have the gas tank, and they didn't have the air box cover.

So, I will skip the pictures of the other plastic being cleaned up (except a few first pics of washing them), and only show the gas tank clean up here.

I had to buy a few different fuel valves for the tank to find one that worked here.

The rest of the plastics came in...

After not being able to find a new condition 1986 KX80 radiator, I found that a 1989/1990 KX80 radiator has the same mounting style. These are available as an aftermarket part, so we went with it.

Similar to mounting the fuel tank, the hardware store had some rubber grommets that worked perfectly to mount the radiator. And, a trip to O'Reilly auto parts helped to find hoses that matched up with the original hose shapes.

While doing this project, I decided I didn't like the look of hose clamps. So I bought a clamptite tool which uses stainless steel wire to make a nice looking and better working clamp. Here are examples of the places I used it around the bike. One includes the exhaust clamps that I previously crimped. I removed the crimp connections for the wire clamp.

I also included a shot of the original mounting of the rear shock accumulator as a comparison









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Finally, caught up. This is the current status of this project as of today.

The items left on the punch list are:

- Radiator strut
- Radiator shroud finalization (the plastic over the radiator)
- Lower chain guide 3d print of final design
- Put on all the stickers.
- Fire it up and see if anything needs to be tweaked
- Wait to see who puts the first scratch in it.