1980 Kawasaki KDX80 back to life

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#16
One "extra" part. I looked through every parts PDF for this model and can't find anything like it. It looks like a wheel spacer but mine are all accounted for. It was in the bucket of parts I got with the bike but that doesn't necessarily mean anything.
extra_part.JPG
So into the parts pile it goes!
 
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#17
So… that just about wraps this one up, I need some new rear brake shoes as the travel is all used up but that’s no big deal.
A few items if anyone is considering such a project:
  • Assume that the guy selling the thing is lying – it will be in much worse shape than he will ever say.
  • Check eBay or some on-line parts stores for part availability before you buy, a good item to check is the carb intake boot – those kinds of rubber parts will always crack and many replacements are long gone. OEM body parts are rare also.
  • Don’t be afraid to order from overseas – lots of these weird parts are actually available from Thailand but go through eBay.
  • Everything takes longer and cost more than you originally thought – that’s just a fact of life and applies perfectly to an endeavor like this. (this took almost 5 months – and I’m retired!)
  • Never, ever, tell your girlfriend or spouse how much you spend on these things – this is self explanatory.
Fill the tranny and put some premix in and it fires right up in 3-4 half hearted kicks, settles into an idle and I am all set. Some photos:
KDX_1_s.jpg

KDX_9_s.jpg

KDX_10_s.jpg

KDX_12_s.jpg

KDX_14_s.jpg

KDX_11_s.jpg
 
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#19
Update,

It fired up ok and ran "fine" but just didn't seem to have any spunk, I have no baseline what this thing should perform like but certainly lacking something. Long story short - the spark arrestor (remember this is a KDX) was plugged up guessing 90 %. Of course its non-removable so I poke and stick whatever I have to free up some flow area. Wind up drilling a 3/8" hole through the center, I will work on something bigger but I need a drill extension of nearly 12".

And ... holy cow, feels like double the hp. I am most pleased. I will look into a straight thru aftermarket silencer but I am not hopeful, the OEM silencer has a curved pipe welded to the main silencer portion so its not a simple bolt-on (think universal muffler) endeavor.
 
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#20
KDX80 # 2 - or here it goes again!

Yep, found another, but this one will not get the "full monte". No powder coating or zinc plating. Tank mostly shot, had to send that out for professional repair. Missing the side panels and front # plate. It didn't have spark - turns out they put new points in it and had to re-solder the wire to the top of the condenser - well - they had a huge gob of solder and that was shorting out on the flywheel, so at least that was a simple fix. At least the crank is good. Wheels and hubs good. The usual, new seat cover, rebuild the forks, new handle bars, and throttle cable, I will keep the clutch cable and front brake cable. The rear shocks are shot but they are all shot this vintage.

The shift shaft was shot (shift lever welded to the shaft) so took the motor apart and checked everything over, a couple of busted fasteners no big deal. Pipe has a 5" hairline crack that needs welding, engine cases needed a bit of a weld job also.

I won't be doing detailed updates like the last one, we'll just see how it goes. Got everything apart and the frame primed:
 

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RM_guy

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#21
I just wondering how hard it will be to not to the "full monte" once you get rolling! Looking forward to see it as it progresses even if you can't do all the detailed pictures.
 
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#22
Engine # 2 is done, the cylinder has a significant score but I'm going to run it for now - bought a NOS cylinder and piston, not sure if that will make it on the bike or not. "Paint Drying" in pic #2, going to be 95 deg today so I thought I would give the paint a good set.
engine_final_s.jpg

parts_drying_s.jpg
 
Likes: BSWIFT
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#23
Assembly - looks just like the first one...
* pipe out for welding - two 3" cracks
* seat out for a new cover
* tank is out for a major overhaul
* a few misc items still on order; rear tire, "Kawasaki Green" paint, misc nuts & bolts, tank decals, front fender

That's my 1978 125RM behind the KDX

assembly_1.JPG
 

RM_guy

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#24
That RM in the background brings back fond memories. I raced the ‘77 RM 125. 3 of my friends made a deal for $1100 a piece and then we bought FMF hop up kits for them.
 
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#25
More:

* Somehow the clowns that owned this thing before threw-out the rubber tank pads - how is that possible? replaced with new OEM ones.
* The non OEM coil was mounted with one 10-24 bolt with a wing nut so I made a real coil mount.
* The rear tank mount is a mystery. I have the correct OEM rubber mounting block but after 2 hours of trying on KDX #1 to make it work I gave up and made my own - same for KDX #2. I cannot find a pic anywhere of what its suppose to look like - very unlike the typical Japanese assembly quality. Its like everything is a 1/2" off - the tang on the tank will simply not fit into the OEM mounting rubber block. I originally though I had a tank from a different model but both these tank are identical.

under_tank_s.jpg