The trials and tribulations of buying a "make run"

[dirt dame 561]

Soooo....I love old 1986 Kawasaki KDXs....so much so that I bought my old KDX back after it went through two other owners. But one wasn't enough, especially when certain parts are simply no longer available. I wanted a parts bike, but it couldn't be JUST a parts bike. It had to be a reliable and at least somewhat attractive trail runner as well. After looking for another stablemate to keep Bentley The KDX company, I finally stumbled across ol' Fugly. I had looked at a few bikes, but the owners wanted way too much for them and weren't willing to deal any on their worn out POS greenies. Personally, I think that I paid too much for Fugly. That being said, I think that anything that isn't free costs too much. This is because when you buy an old bike, you never know exactly what you are getting (unless you buy it from me, of course). Let's say you pay 300 bucks for something that "ran before I parked it ten years ago". How good is that guy's memory really? Probably only about as good as the shape that that bike is in. If it is truly a "make run" bike, where you just overhaul the carb, grease up the cables and maybe throw some fresh tires on it, then you probably got a good deal. But you never know what will happen once the bike fires up and doesn't run the way it should.

Welcome home, you green piece of neglected dookie.

Take ol' Fugly f'rinstance. I soaked his carb overnight in parts cleaner and blew out all the jets and passageways in the carb body. The engine fired right up (after about thirty kicks, anyway, and black goop ran out of the muffler for about fifteen minutes before the engine cleared) and I rode the little machine back and forth on the easement. It felt pretty snappy, but wanted to load up at idle. The jetting was all pretty lean compared to a normal KDX of that vintage, so I wondered what might be wrong. A quick look at the reeds showed that they were pretty burnt up and all warped. I dug up some used reeds from Bentley and popped them in. The bike ran better, but I had gotten a peek at the backside of the piston while I had the reeds out and it looked pretty sad. The bike felt like it had plenty of compression when I kicked it, but that wouldn't tell an accurate story. So I popped the head and drew the piston to the bottom of the stroke. Aluminum was sticking to the cylinder wall in a couple of places and there was a gouge or two. Hmmmm, probably the victim of too many unscientific jetting experiments. I decided to check the main bearing on the ignition side of the engine. The seal hadn't leaked and there was no play in the bearing. It was an encouraging sign, so I ordered a piston.

Yummy....the dirt was stuck to the machine like cement.

While waiting for the piston, I decided to go through some of the other systems. I started at the back of the bike, since the rear brake locked up on me when I applied it on the driveway. Yep, the shoes were worn out. I popped on a new set. Drive side wheel bearing was rough and loose so I tossed one of those in too. Linkage was okay, but I wanted to change out the oil in the shock. But the bumper was missing, so I would have to take it all the way down, and since I was going to go that far, I might as well put in a fresh sealhead.

Though the shock fluid was practically pitch black, the piston bushings had minimal wear.

Why a purple shock spring? Why not? Hmmmm, looks like I have one too many vent hoses hooked up in this picture....

When the piston arrived, it was the moment of truth. And the truth was that the cylinder cleaned up nicely with a flex honing, but I couldn't bring myself to put that nice piston on top of the wilty bottom end. Sure....the rod would go on a little while, but it is simply not in my DNA to do that kind of repair. It was time to order main bearings, seals and a rod kit and dive in.

Luckily, I was psychologically ready to build this engine (even if not so monetarily so ).

Doing the splits, MC engine style.

Cruddy rough mains, but the transmission looked as though it had never been used!

There weren't wear marks on any of the shift forks or dog and slot interfaces of the gears. Tranny bearings all ran smooth. It was a purdy sight.

The dirty black heart of the scoundrel, now languishing in the garage, waiting on new parts. Oh wow, now I have time to rebuild the forks!

Now some of you might ask why I would get a junker and do a complete overhaul on it? The answer is that when I am done I will have a good ol' pal of a bike that I will cherish and it will run great for many trouble free years, since I took the time to fix everything on it. I might even make some time to make it look pretty.

Stay tuned for when the bike that will soon be known as the former Fugly gets his new name and a photo shoot.

[mctrails 38]

Interesting story because I'm in the middle of the same project with a 2004 KTM 200. Big differences are my parts are really expensive and I needed A LOT of them. Just finished buttoning up the engine 2 hours ago so things are moving forward. I need to do the suspension and then put it all back together.

I think you might finish before I do. Good luck with the rest of your project. Maybe we can do a break in ride together. That would be cool.

[Spaugh 1]

Nice work mimi. Are you using ATF?

[TrophyHunter 15]

I put air in my tires when they need it.

Nicely done Mimi...!

[kkug 147]

Mimi --nice collection of Bead Hones. Looks like you are realy set up. Good for you.

[BelnapAir 0]

Wish I had your tool collection! Nice work on a quality build!

[Bagstr 288]

Great to see a journey woman at work. Thanks for sharing the process.

[dirt dame 561]

Nice work mimi. Are you using ATF?

I am using ATF type F in the tranny (1.78 a qt at Walmart!) and Dextron III in the front forks.

Wish I had your tool collection! Nice work on a quality build!

I have lots of tools because I worked at a dealership and was trained by Kawasaki Motor Corporation in Santa Ana and also later on ran a repair shop. I finally sold my Serviquip cylinder boring machine last year to some CZ vintage shop in Nevada because I hadn't actually done any bore jobs since about 1990 and the machine took up a lot of space in my already overstuffed garage. I still have all the rest of my tools though.

[dirt dame 561]

So I got my rod kit and started to press down the crankshaft assembly.

You can see where the conrod was riding directly against the cage instead of the pins.

Pressing out the other side.

All ready for a new pin and all the trimmings. Where did I set that kit down?

Oh noes! Houston, we haz a problem! So I had to call the manufacturer of the rod kit and get them to mail me a new thrust washer. Guess I won't be putting that crank assembly up today.

[Spaugh 1]

please post pics of your crank rebuild and balancing and the tools\jig you are using.

[Zenosan 2]

I like your press set up Mimi. Mine looks clunky compared to yours.

[robertaccio 412]

good move on the deeper and deeper rebuild.

you know that it would failed at the far end of the riding area in the most inopportune moment on a weird hill or something similar. Good work you are getting very well aquainted with the latest greenie in the stable.

[dirt dame 561]

please post pics of your crank rebuild and balancing and the tools\jig you are using.

Those pictured above are IT (well that and a truing stand with knife edge bearings and a dial gauge). I only have the takedown tools and a twenty ton press, which can also be used to help put the crank back up. But as far as a crank building jig, I have nothing. I measure the width at four points around the flywheel halves before they come down, then scribe a guideline across the two halves directly opposing the side where the crank pin goes in. First I have to visually line up the crank as I prepare to press it up. The halves cannot "walk" at all. After I have the halves lined up that way, I can press for clearance and adjust toe out and toe in till I manage to achieve less than a half thousandths of run out on the truing stand....or I can repress the dang thing trying to get the "walk" out of it until I tear my hair out and find somebody with a building jig and have them jig it up and press it.

[Spaugh 1]

please post pics of your crank rebuild and balancing and the tools\jig you are using.

Those pictured above are IT (well that and a truing stand with knife edge bearings and a dial gauge). I only have the takedown tools and a twenty ton press, which can also be used to help put the crank back up. But as far as a crank building jig, I have nothing. I measure the width at four points around the flywheel halves before they come down, then scribe a guideline across the two halves directly opposing the side where the crank pin goes in. First I have to visually line up the crank as I prepare to press it up. The halves cannot "walk" at all. After I have the halves lined up that way, I can press for clearance and adjust toe out and toe in till I manage to achieve less than a half thousandths of run out on the truing stand....or I can tear my hair out and find somebody with a building jig and have them jig it up and press it.

sounds fun. you could end up with a nice vibrating bike. may or may not be a bad thing.

[dirt dame 561]

sounds fun. you could end up with a nice vibrating bike. may or may not be a bad thing.

Trust me. I once put an engine up that was one and a half thousandths out. It was not a lovable ride.

[DustyRock 0]

Koooool ! I havent split the cases on a bike (read happy) since my Maico 440 chipped a couple of teeth on 2nd. Good feeling to be able to do this stuff yourself. Very nice write-up & the pics make it all come together. Thanks for sharing.

[dirt dame 561]

So the right thrust washers arrived for the rod kit. Thanks to the Hot Rods folks for getting those out to me as quickly as possible, as they are not a local company. And up went the crank assembly.

It was absent when I split the crank, but I always use a piece of aluminum between the ram and the crank part when I put the crank assembly back up, so if the parts shift slightly, the ram can't actually ever accidentally touch the crank spindles and ruin them in any way.

The crank is marked so that I can visually align the two halves, then a straight edge is used 90 degrees from the pin to keep "walking" to as close to zero as possible, since I don't have an expensive truing jig. As the rod goes back together, it's time to make sure it is getting pressed to the proper side tolerances also.

Then, once it is out of the press, recheck the side tolerances again. This crank calls for 16 to 20 thousandths. I have 18.

I also check the width of the halves every 90 degrees to make sure that the tolerances are what they should be from point to point.

Then I check the run out at the farthest smooth point of each crank spindle. The crank will have to be wedged or pressed or possibly just whacked with a lead hammer to get the high and low runout out. Sometimes the crank has to be pressed back apart and realigned to get the last tiny bit of "walk" out of it. Any walk at all will make it virtually impossible to get the two crank spindles axially aligned and get all the runout down to a half thousandth. This is the most frustrating part of the job. Once the crank has less than a half thousandth of runout on each spindle end it is ready for re-installing into the case halves. Now I am just waiting on the main bearings and seals to arrive.

[dirt dame 561]

Been waiting on some parts and a parts washer to arrive. Today was my big day when all the elements came together and I got to put the bottom end back up.

Mmmmm, fresh, clean solvent.

Followed by fresh. clean main bearings and seals.

Next, it was time to put the rebuilt crank assembly back in. It is wedged so that the pressing will not cause it to toe in on the installation.

Ready for the tranny.

The shift drum goes in first. Make sure that it is set to neutral before installing the rest of the transmission.

Then in go the gear clusters, followed by the forks. They should fall right into the correct grooves on the drum when engaged in their respective slider gears. Then it is time to push in the fork guide shafts and spin the transmission. If everything has been done correctly and in the right order, the gear box WILL be in neutral.

Now to goop up both centercase halves with plenty of RTV. This engine doesn't utilize a center gasket, so great care has to be taken to be sure there is the right amount of goo to ensure a good seal between the halves when the cases are pressed back together.

Whee, all buttoned up and the crank assembly has been recentered in the finished case. There are no left over parts and everything looks good, so I guess it's ready to slap back into the frame.

[TrophyHunter 15]

Mimi - thanks so much for posting all of that. I know it's tedious to stop and take pics and share the process. It it appreciated!

[dirt dame 561]

I've never photo documented any part of a rebuild before. It's sorta fun. I couldn't do all the pictures required for each step (because I'd need either a tripod or more hands and then I'd be creating a service manual ).

[Bagstr 288]

Delightful Mimi, Thanks.

[Uncle Champ 116]

Mimi, as I recall you were looking for a job a while ago, what the heck - I make a living as a mechanic and you are WAY better than me when you are just screwing around on your own stuff. Hmmmm ever thought about starting your own place?

Seems like you have quite a following already.

[dirt dame 561]

Mimi, as I recall you were looking for a job a while ago, what the heck - I make a living as a mechanic and you are WAY better than me when you are just screwing around on your own stuff. Hmmmm ever thought about starting your own place?

Seems like you have quite a following already.

Back in the 80s, I went through a general motorcycle technician course, and then went to many classes to become a certified Kawasaki technician when I worked at a dealership. I did run my own shop (The Motorcycle Works and then Elite Motorcycles) for many years (hence all the correct tools and fixtures for most jobs). I do work on the side for people as often as I can, and not that I would completely disregard considering it....but being a technician full time is not the first career choice that I would make these days.

[dirt dame 561]

Well, I should have been enthusiastically posting pictures of the rebuilt KDX by now, but the truth is....that it won't run worth a darn with it's own carburetor. It will run perfectly with the carburetor from Bentley The KDX however. Since I have carefully cleaned, inspected and readjusted every part in the resto carb so that it has all the same jetting values as Bentley's carb, in theory it should run perfectly. This has led me to the conclusion that the carb body has some hairline cracks in the venturi and gasoline is leaking up from the floatbowl at an unknown and unmetered pace. No wonder the previous owner had the bike jetted so terribly lean, trying to correct and uncorrectable problem. All that got him was a starved lower end, seized piston and burned reeds before he threw the bike in a corner for a few years.

Now all I have to do is come up with the not terribly common "righthand" Mikuni VM34 body with an oval bore in good shape, and the project will be finished. Finding that carb won't be very easy though. I'll have to keep my eyes peeled on E-bay.

[dirt dame 561]

The carb on the 1986 and 1987 is built so that the idle screw and choke can both be accessed on the righthand side of the motor. There isn't even an air mixture screw on this carburetor. The lefthand side of the carb is riding right up against the backside of the airbox, so close that even the venting had to be modified so as not to be pinched by the airbox. There is no other machine (besides same era KX) that takes this setup that I know of. Every other carb has all of it's adjustments and settings accessible from the lefthand side of the motor.

Peek a boo. I don't see you....you Mikuni, you.