just bought a ´87 kx250

[sandblaster]

I think you, build it, modify it, and race it.
What more needs to be said?
The man of steel is awesome!

[motopunk]

tomorow in the evening i and my father will do all the weldings on the exhaust and headstay...  and then comes the jetting...  in every frame i used this engine was also diferent jetting. and this time is also a diferent carb in the game... starting with the last working set up... and we´ll see what happens...  


i need a 97-reedcage and the last setup will work properly without major-changes... ;O)

[motopunk]

...the headstay...


... man at work...


....the modified 360 exhaust...


and...in the evening after a little jetting with the old keihin- pe carb and ignition-timing to the longer stroke of the 360 :


...she runs like hell ... ... now i can use her on evo-race at 10.august ...  

in the next time the bike becomes an update with an used 38mm keihin pwk-airstriker-carb, boyesen dual stage reeds, and a 97-reedcage for a better linear power delivery, like i rode this engine in the past... still waiting for this parts in the mail.



also thanks to sandblaster for a very good parts price...   ...

[motopunk]

new year and time for update...  
first i fixed the transmission of my 87-motor . it wasn´t not as half dramatical as i thought. a snapring was out of direction. gears still looking like new. so i replaced all snaprings and washers..


.. but what i also found in the engine, made me shiney eyes. one of the very rare lighter weight works-cranks is in there. under the seat i found the name of a guy who sold some new kawasaki-vintage parts to me 2years ago. i contacted him and he stated, that my bike must be an ex-team tuf-racing bike, that he imported and raced in 87 and 88 .
now i know, why the engine runs so easy handling, but strong and powerful.


played a little bit with 2003 fenders, because the german importeur for ufo and mayer plastics is out of busines . so its hard to get a new rear 87 fender without paying 5x of the normal price.


sandblasted and painted the camouflage-frame in kawi-green



and... now i can realize my long planned fork-change-project..
out are going the 89 41mm usd-forklegs


and now in going forklegs of a 50mm wp-extreme conventional fork from a husaberg 501.. inner diameter of the upper clamp is the same like the wp-clamps, so i needed only 2 buschings , that my father made for me.


still without frontbrake, but looks awesome. the fork is the best conventional fork, that was ever made and sold to the public. performs like a knife in warm butter  

[sandblaster]

Looking very good!
Broken snap rings on the trans shafts are more common then you think.
I have bought many bikes with that same problem.
That's a good reason to replace them during a rebuild.

[motopunk]

thanks... and i cant wait to make first testride,to feel how much diferent the fork will perform on the mx-track, but without frontbrake it will be kamikaze... ... as i bought this fork, i could tip with only one finger on the upper clamp and it moved a little bit... no other of the stock or modified forks, that i ever rode, was performing in this way...

with the tranny i thought first, that it is much more damaged, like it was on my 83 kx250 ...  snap rings getting old over the years and loose their tightnes... and on a used bike, you never know, what all was happened over the years...  as i picked up the 87, there was nothing except the fresh piston, that not needed attention.. and slowly step by step it turns into a blue/green diamond... 

last year i could so much things not do, because of the breathing problems and headache around the clock. sometimes i could eat painpills like bonbons and nothing happened. and now 3 months after surgery it goes slowly back to normality... and holy s**t..with this handycap and hard painpills i made my last 3 races last year and was at least second place all over in the championchip...only ten points back to get the champion... ;O)

[bens87braap]

Awesome love it great job

[bens87braap]

What gearing ratio is good for all round ridding on the 87 mine is 13t  47  and out on the trails im allways looking for a next gear.  Should I change front or rear or both?

[motopunk]

What gearing ratio is good for all round ridding on the 87 mine is 13t  47  and out on the trails im allways looking for a next gear.  Should I change front or rear or both?

the oem gearing was always 14 -47 from 1983-1989 ...you should try this first.

 it works good for all kind of riding conditions.. for mx i change the rear sprocket sometimes into 48 or 49 . that allows in deep sand or mud to use the next higher gear a little bit earlyer   

changing the countershaft sprocket to +1 or -1 effects roundabout the same change of 4 or 5 teeth on the rear sprocket.
you can calculate it a little bit :
divide rear sprocket and counter sprocket and you get your ratio. the bigger the number you get = slower bike, smaller number = faster bike

example : 47 : 14 = 3,357   
              47 : 13 = 3,615 

              3,357 is smaller than 3,615 (your actual gearing) , so it will be faster by the same rpm´s the engine makes ..

[bens87braap]

sweet i will jump up to a 14 front and leave the 47 on rear i will let ya no how i go after shocks arive then I can ride again soo upset without a real dirt bike 

[bens87braap]

I read this topic and love it I wasnt game to fabricate my own pipe so i waited 5 years until I for one I think i was Luck to get my pro circuit pipe from California off Ebay for 80 AUS cost me more than that to get it posted down under 

[motopunk]

I read this topic and love it I wasnt game to fabricate my own pipe so i waited 5 years until I for one I think i was Luck to get my pro circuit pipe from California off Ebay for 80 AUS cost me more than that to get it posted down under  

with the gearing always go the easiest way... 

this pipe-modify-rebuild was my only option . the pipe on the bike was simple scrap. no good used were offered on the market and i had this old 96-pipe still laying around. that was worth the try and the bike runs great with it  
on the 87 kx 250 could used aftermarket pipes of the 88/89 that still offered new by pro circuit and fmf... but i found them also only in us...

[bens87braap]

i looked at the 89 exhaust option is it just the springs and location of the springs all that is different?  the pics i see have 2 springs where the 87 has 3? 

[Goat]

 Looking good. I do miss the camo paint job though 

[motopunk]

i looked at the 89 exhaust option is it just the springs and location of the springs all that is different?  the pics i see have 2 springs where the 87 has 3? 

thats not important enough to  use only 2 instead of the 3 springs. it will still work... the 3rd spring can also hooked  up in the same hole upside of the pipe on the flange... 

on my kx500 conversion i use a honda cr500 exhaust . the cr500 pipe is mounted with 4 springs to the cr500 cylinder ... but on the kx500 cylinder are only holes for 3 springs..