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Young&Fast
June 13th, 2007, 15:17
1984 KX 125
From Waste of Space to Racer
Part II

I finally finished stage II yesterday: Engine work. When I took her apart I found that the engine was seized and it was already sleeved with an oversized piston. Which the guy I bought it from had no clue about. I was going to put in the new top end in back in April but the piston was the wrong size and I didn't get the new wiesco until about three weeks ago. I also painted the cylinder, head, and case in high heat paint. Everything on this stage took so long because I had school and lacrosse to take up all my time so I was lucky to get a few hours a weeks to work on the bike.

I also rebuilt the clutch and spent way too long trying to figure out my "Shifting Problem". I spend about a month trying to figure out why the bike wouldn't shift. I finally had a friend who is a mechanic check it out and it turned out to be that I put the shift lever on too low and the lever hit the frame before going into gear. Man, I felt like an idiot.

I also had the cylinder honed and I had a horrible leak out of the rubber intake that most likely caused the engine to seize. I ended up having to seal it with implant grade silicone. I had to use implant grade because it is pure and does not have any hardeners that would cause the silicone to crack and start an air leak again. I also made a custom silicone "torque spacer" that fits between the reeds and the engine to provide more bottom end torque.

I finally got her together and running the other day. I took forever but I had a lot of fun and learned a lot.

The next stage will be cosmetics and tune up. Brakes, fork seals, suspension tuning, new silencer…

The thread before this one: http://www.race-dezert.com/forum/showthread.php?t=26630

Young&Fast
June 13th, 2007, 15:36
Top End:

Young&Fast
June 13th, 2007, 15:44
Clutch:

Young&Fast
June 13th, 2007, 15:52
Miscellaneous:

Young&Fast
June 13th, 2007, 16:38
Here is a video of starting her up. The camera makes the sound messed up a little, it sounds healthy in person.

YouTube - '84 KX 125 start up