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               Project: KX 400


It was one of those magical moments. I sat down on Ebay, and ran one of my usual searches. I wasn't really in the market for a bike, but it's like women. Its fun to look anyway! About three items down on the list was a bike that caught my eye. I clicked on the listing, and saw what looked like an old Kawasaki dirt bike that had been sitting for some time. At first I thought it was a garden variety F11, but the closer I looked at the picture, the more I was intrigued.The listing gave the frame number, which started with a K5. I wasn't sure what that was off hand.  The pipe swept down and back up behind the shocks. It had a number plate, and the fenders looked like they were plastic. The rims were aluminum. There was no sign of any lighting or road gear at all.

I didn't have much time to decide about the bike, since the auction was going to end in 3 minutes! No kidding, from the time I found the listing to the time it finished took less than 5 minutes. I knew that this was something special, so I put in a bid at the last minute. I won the bike for $117.00. It was a bargain either way, and I figured if it turned out to be a turd, I would just part it out and make my money back. I called the guy, and arranged a pickup for a few days later. He wasn't sure what it was and neither was I.

Here's a picture from the actual auction:


 When I picked the bike up, it seemed pretty small to me. I thought it was going to be a 125 or something, but a close look at the cylinder revealed a "401cc" marking. YES! So what I have is a 1975 or 76 KX400. Im not really sure which one.

I got the thing home, and gave it a thorough examination. It was mostly there...side covers were intact, the brake cables were really nice, and the levers were beautiful with nice rubber boots. The rims were in really nice shape, although the front tire was bad. The chrome had flaked off the handle bars, and there was some rust on the forks. An earlier owner had painted over the metallic lime paint with some drab ass green. The thing was dead stock, and I dont think its ever been apart before. The engine turned over, and had some compression.

I wasn't sure which way to go with this one, so I just started taking it apart. I took it down to the frame and engine and gave it a good cleaning. Ive already rebuilt the carburetor but it was missing the jet needle. I removed the top end to inspect the crank and bearings. This thing has still got the standard piston in it! There was a good bit of scoring on the piston and the cylinder so I think I am going to have it redone. The rod feels perfect and the main bearings feel pretty good. I dont plan to touch the bottom end at this point. I wish I could have gotten away with a set of rings or something but I think its best to have it bored even if it means that the project may sit for a while. I had thoughts of polishing the piston up and putting a ring set in it, but that would not be doing justice to this machine.

All the magazine articles pretty much say the same thing about this bike. The engine made more power than any other open class machine of it's era, but shortcomings in the suspension and handling meant that you couldn't make use of that power on the track. "IT WOULD HAVE BEEN DYNAMITE IN 1972!" Proclaimed one article.  The steering was praised as precise and quick most of the time, but on the power it tends to wash out. The suspension, well  "unpredictable" was the word most used to describe it. What it boils down to is that if anybody had the balls to push this thing to it's limits, you just might get dumped on your ass or washed out into a ditch. So, all in all, more power than the frame and suspension can handle....Hmmm, sounds like a Kawasaki to me! It falls right into that era where engines started getting scary fast, and before the long travel revolution. 


Update: 4/2006

I did some work on the tank. Cleaned it out, cleaned up the valve. The original paint was underneath, but I damaged it somewhat stripping the shitty spray can job from it. I think with a little detailing it ought to be presentable. Its very straight, with one tiny ding and that's all. I would have to pay a few hundred to have it painted properly and new decals, but Im not going to bother right now. That's never a priority for me. Maybe one day I will do a proper restoration but not now. Cant afford it.

Top end is in a box. Pistons are ultra unobtainum. One guy had them made as a short run at Wiseco some time ago, but they are almost gone.(By the time I can afford one, they will probably be gone) He assures me he is the only one on the planet with these, although I have a line on another source, so Im not too concerned. 


UPDATE:  3/07

Well, the 2007 season starts in 3 weeks. March 31st is my first race. I have been working on the KX a bit these last 2 weeks, but Im not sure if I will have it ready.

I went green with the frame.

I need some minor items before I can start it up. Jet needle, throttle adjuster etc.

The tank really turned out well!

Update: June, 2009....

 Well its been a while. I ran the KX a few times in '07, along with the bighorn. Somewhere in  early '08 the bighorn broke down and I was forced to ride the rest of '08 on the KX400 which forced me to get to know it a bit better.

The KX400 has made me a much better rider. It demanded it. You can not ride it easy. It needs to be pushed, and it responds very well. It acts VERY much like a 125 on steroids. Theres really not much bottom end to speak of, its peaky, and it likes the juice! It never seems to run out of RPMs. This bike is the lightest, nimblest and best handling bike I've ever ridden. The suspension, bone stock, just soaks up the bumps. I still had trouble turning, but I dropped the forks about an inch in the yoke, and all of a sudden it turned really well.


2009 at Roaring Knob

The 400 is getting a little noisy.... I think I will put a new piston in it at the end of the '09 season. No bores yet. I gotta be the only one running on a standard bore I bet!


2009, again at Roaring Knob

UPDATE 2012:

I have been racing the 400 alot, it's been my most reliable bike so far so it's the go to machine for me. It handles so well, I am really getting used to it. I still think if I could tame it down with a flywheel weight I would really kick some ass. I can be a total hooligan on the straigts, there's no bike I can't run down in a straight line on the 400. However, tight turns and numerous obstacles require alot of careful shifting, you must be in the right gear coming out of the turn or getting ready to go up the hill. There was one large hill after a turn that I had a hard time with. 2nd gear would run out to quick....3 gear would peter out half way up. the only way was to take the turn in 3rd and keep the RPMs up, feather the clutch a little, then blast up in third with the Rs already up. Its techcnique I am working on.

Oh yeah, I got the piston coated...its still pretty noisy. I should have gone with the "thick" coating. LOL... who knows. I am on my third set of standard rings and still the same old slug the thing had since it was new.