about 3 years ago i aquired an 86 kx500. it was hammered in every way you could imagine. the motor was out of bike, had a busted up case, broken clutch cover, cracked/ broken clutch actuator/ chain guard, lots of little things. you name it, it wqas probably shot/ broken on the chassis. fork seals, shock seal/ bumper missing, shock preload ring stripped on body, frame cracked in about 4 places. there were no lower engine mounts, the swingarm pivot was loose, the upper mounts loose, front mounts broken. radiators tweaked/ smashed, etc etc. nothing on the rear wheel was usable. the swingarm looked like the chain came off a hundred times.
pic of bike. doesn't do justice to how wrecked it was
my plans originally were to use the motor for an 08 kx450f i had, but i grew up riding 80's kawasakis and couldn't scrap this thing.
so it sat untill last year sometime when i decided to overhaul it.
i started with things i knew i needed to do. never liked the mini footpegs, so i made some 02 up cr/f foot pegs work
then was the pipe. every old kawaskai i have ever owned had a pipe that rattled. this bike has one small mount under tank. so i started to weld more tabs here and there, but also beeefed up the one that was already there. used mainly honda mounts everywhere. my pipe had been repaired liek a zillion times, so i had to fix as well
new lower mount
started with hacking off the rigged stuff
new upper mount, made from 5/16
new rear mount
blasted, de carboned and ready for ceramic
ready to mount
i had a 88 up silencer already, it bolted right up to the 86 mounts
silencer de carboned, 2.5" trimmed off, packed and ready for use
oem fuel tank, looked typical for old kx
found a smaller 86 kx250 tank, it was pretty bad looks wise as well, cleaned up and ready to mount
wanted a skidplate, had some 450 thing, hacked up to make fit.
made a new front hold down, notched hole for drain plug, fits the kx frame perfect now
cases coated with heat dispersant, ready to go together
shift parts moly coated
getting motor together, surf and turf racing balanced/ rebuilt the crankshaft
slotted clutch basket, drilled hub
hammered radiators
planned on using 88 up radiators, just a few things different than 86 model
the right side on 88 up is hair shorter, so lower mount tab needed to be lengthened, and middle mount on 88 up is on rear, 86 needed it in front. 88 up also has two shroud mounts, the 86 has one in center
the left side is exactly the same minus the midle mount and the shroud mount
radiators all welded up, coated with heat dispersant. need to drill the hole for shroud mount. these are some oversize jobs
for the motor i needed a new intake manifold, mine was cracked pretty good. could not find one, so i took a boyesen rad valve, re shaped to make right.
before, oem 86 on left, 87-04 rad valve on right
i had to flip the reed cage once the bend was cut off, then massage on inside a littlle more to get it to line up where the old one was. all welded up and good now. in the end the rad valve is a clamps width longer than oe, but my new carb is that much shorter than the old mikuni, so all is well
about the only good parts on my motor were the powervalves. when i went thru the engine, i moly coated the outside of drums, and used slik ceramic in exhaust port/ powervalves
cylinder got leaned on pretty good, ought to run pretty right
bike had a sleeve, needed a bore. piston got moly on skirt, ceramic up top.
completed engine
the head on this bike was pretty warped. cut a bunch off to make right. reshaped the dome, etc etc. had a compression release put on it. also made adjustable stop to make the powervalves right
rad valve incognito
i plan on putting motor in tomorrow, hope to race it this coming saturday.