1993 KX250 Build, Mechanimation Project (Build Complete)

At long last the engine rebuild video is done and I can move on to the next part of this project!

https://www.youtube.com/watch?v=wrrkDxsRKlA

His FB: Metro Lakes
He doesn't have an online store so if you're interested in pricing and details they can be found here:Mxrevival

The engine stand is very sturdy, well built, and super functional. I bought it because it made this video easier to shoot and better to watch, otherwise I don't do enough rebuilds to justify the cost. Now that I have it though, I wouldn't want to go back.

You can be great at editing without being crazy enough to try stop motion! 😂

I think this engine stand definitely falls under the "buy once, cry once" category. I can't imagine any normal usage breaking the thing.

That's cool to hear, you're raising them right! The whole flying T handle idea came from those propellers on a stick that you'd make fly by spinning between your hands. I loved them as a kid and started spinning T handles like that the first time I ever picked one up. Maybe this will get their imaginations going too.

Having used the good powervalves I had on this engine for the video, I was left in need of a set for the second engine. As most KX owners are aware these parts are no longer available new.

After some debate I decided to take a chance on ordering some from a Czech dude who machines new ones and sells them via his FB page Kawasaki KX Power Valve - KIPS. He has many other years and models available as well. I ordered them 11/13/2020, they shipped 11/25/2020, and I received them 12/18/2020. I have installed them in the cylinder with all the other components in place and the fit is excellent. Everything moves with very little play/slop.

The price for everything you see pictured was $225 shipped and I am happy I went this route rather than trying to find a decent set of used parts. Just a FYI for anyone who may be in a similar situation.

Well, I finally feel like I'm making some significant progress on this project.

First up was repairing the frame. Let me start by saying that I know this isn't high level welding, but I think it will hold up for a couple of parade runs. If I decide to ride this thing seriously at any point I'd probably use the other frame as it's in better shape all around.

Before:




Bringing the foot peg brackets back to parallel. We used some heat to help as the bolt was used to draw them together.



Partially cleaned up before welding. the threaded rod was used to get a rough idea of alignment compared to the "frame of reference".





Farmer welds complete





Both frames are now off for blasting. I have some threads to repair, a brake pedal post I'm going to replace, and I want a good look at any other work that may need to be done before powder coating.

More miscellaneous progress

First time lacing up a new wheel. I'm going for the stock look, so silver Excels on vapor blasted stock hubs it is. I haven't fully tightened up and trued them yet, but so far it's been fairly straightforward.





This engine has given me a bit more troubles than the first. The broken bolt was a pretty easy fix since there was enough protruding to get a nut welded to.




Removing the water pump bearing, however, turned into a full six pack's worth of time and effort. The ID of the bearing is 6mm and the smallest puller in my set was for 8mm. You can stuff it in there but it doesn't get a full grip on the inner race. I tried the puller several times while heating the case as much as I was comfortable with, but succeeded only in messing up the collett.



So I decided to try stuffing behind the bearing with grease, then wet paper towels, and using a punch to drive the bearing out. I had little faith it would work, but was out of options.

After a half hour or so I made no progress.



But after adding some heat to the mix it finally budged!



At this point I went back to the mangled bearing puller and got it the rest of the way out.




On the less successful side, I am 0-2 on useable shock bodies. One body has bad threads to the point I can't remove one of the preload collars, and the other has worn through the anodizing. If you have a useable shock body I'm in the market.



Here's a few pics of tearing them down.

I was having trouble finding a chain slider for this era of KX's, but eventually found Hotfoot Moto. After some consideration I decided to give them a try for the slider ($35) as well as the chain guide and rub block assembly ($55). The chain guide parts are still available OEM, but the HFM parts are significantly less expensive.

They arrived today and I mounted them up. The fit is good on both the slider and the guide. As you'll see in the photos the parts lack the finish of something from Acerbis or TM Designworks, but a little time with a razor blade went a long way in cleaning up the extra material left over from the mold. The reviews seem very positive in regards to the durability of these parts and if that's the case I'll be happy. Either way it's nice to have an option at least.

The worn area is larger enough that I'm thinking it's too far gone, but I really don't know how one would measure it. I just assume that the aluminum wears really fast once the anodizing is gone.

It's way overdue, but I'm finally getting around to providing a build update. I actually finished the bike last spring, but I was so burnt out on the whole deal I haven't had the motivation to make a good post about it. As with my previous posts I hope to provide as much useful information as I can.

Let's start with color matching of powdercoat, plastics, etc. I looked around and agonized quite a bit over this before making my decision. In short, I am plenty happy with having used the following combination of:
• prismatic powders Kiwi Green powdercoat
• UFO plastics
• Evo Mx replica graphics
• OEM radiator louvers

The following pictures should give a very good idea of the color matching. In my internet research the only potentially misleading advice I came across was people simply saying "RAL 6018" would be a match for the OEM paint. I included one picture with a RAL 6018 color sample as an example, and I'm glad I went with kiwi green.








Brakes
I got the brake calipers and master cylinders vapor blasted, then rebuilt with a combination of Pro-X and OEM parts. I went with the OEM brake pistons front and back after not finding any aftermarket options that I felt good about.

Had I known about Titan Classics before ordering the OEM pistons I probably would have given their titanium caliper pistons a try. I'm not trying to go all out on this build, but in this case their Ti brake pistons are cheaper than OEM parts so why not? They also sell some brake pins that aren't available individually from OEM, and appear to be reasonably priced, high quality stuff. Maybe if I go ahead with building the second bike up I'll give it a try.








One mistake I made regarding the brakes was not paying enough attention to the condition of the rear caliper. In this pic you can see how worn down the... I dunno, prongs?.... of the front caliper are vs. the one in the back. I had everything assembled, filled with fluid, and bled before I noticed the outside pad was nowhere close to flush with the rotor as a result.



The rear brake pedal and its mounting point on the frame also gave me some headaches. I need to mention at this point that I decided to use the frame off the "donor" bike instead of the one pictured above. Anyway, the brake pedal had all kinds of slop and the pivot point was in rough shape, having been drilled out and re-threaded at some point.



I ordered up some hardened round bar, cut it to length, drilled and tapped a new hole, and welded it into place. The bushings were pressed in to the brake pedal and everything worked out pretty well.






Zinc Plating
I also decided to try my hand at zinc plating, since there were quite a few bolts, axles, and miscellaneous parts that are no longer available or I didn't feel like paying for. I definitely didn't get the perfect super bright look, but the more satin looking finish is good enough for me. These results were achieved in a solution of vinegar, epsom salt, and sugar. The cheaper DIY option compared to buying a Caldwell plating kit.








There were definitely some mistakes made along the way learning about the plating process.


Ignition System
Another new one for me was taking a deep dive into the ignition system, specifically the stator. I had the bike assembled far enough that I could test for spark and there was none to be had. I started by swapping the ignition coil with my spare unit but still had no spark. So I dove into the manual, busted out the multimeter, and started testing resistance across the coils. If I remember correctly it was only one of the coils that was out of spec, but due to the condition of the coils I decided to replace them both.

The stator plate and lead wires from the original bike were in far better condition than those from the donor, so I chose to solder the good coils into that unit, rather than replacing everything at once. My soldering skills are lacking, but I think they'll be functional. After swapping out I had a nice spark. Chalk up another win for the service manual.






That's most of the unusual or possibly helpful stuff. Here's a miscellaneous photo dump from other parts of the build.











Like any restoration this has taken far longer and cost far more than anticipated, but I'm happy to have done it and get a great deal of satisfaction every time I look at the bike. This is how I would have loved to do it the first time back in 2002.

So here it is, the completed Bike:

I have some updates on the video side of things as well. I finished the engine rebuild video and posted it to Youtube back in December of 2020. Among the feedback I got was someone suggesting that I should enter it into a motorcycle film festival. I had no idea that such things existed, so I looked into it. Long story short, I have entered it into 3 moto film festivals.

The first was the Santa Cruz Moto Film Festival, put on by a group called Revsisters. They do multiple motorcycle film festivals throughout the year. My video didn't win anything in this festival, but they did include me in their filmmaker interviews due to the amount of interest they saw in how my videos are made.

The second one I entered was the Toronto Motorcycle Film Festival. As far as I can tell this is the biggest motorcycle specific film festival out there. I am happy to say that my film won the "Best Short narrative" category.

My third entry was to the World Of Echo Film Festival. Jared Conley runs the motocross website inaworldofecho.com and this was his first year branching out into doing a motocross film festival. It seems pretty clear to me that his site and this festival are passion projects that he does for the love of it and not for financial gain. Given the amount of time I've put into this passion project of mine I can relate. That being said, Jared's festival was the only one to offer cash prizes for the top 3 finishers, and my second place finish in the short form category won me a bit over $500.

That's pretty much where things sit with Mechanimations at this point. I didn't make these videos with any ideas of film festivals and such, but I'd be lying if I said the recognition wasn't rewarding. Even so, I haven't had the slightest desire to do any more animation. Even if I did I haven't had any ideas for what the next project would be. Stepping away for a bit, riding my newly acquired YZ450F, and getting back outside a bit more have all been welcome changes.

Funny you should mention that, I had the same thing happen. I had to get a long drill bit in there to get the broken off pin out of the cylinder.