Testarossa's 78 KZ1000 Fighter Build

roy-b-boy-b wrote:

As concerning the bearing. I have seen bearings with the same,as you call bumps.
I doubt they are bumps. I would make a wild guess and say the engine has probably set for a extended period in hot and humid weather and condensation set in.

I personally would reuse the bearings. Use scotchbrite to remove the bumps.

Roy

Roy,
Upon further examination, they are definantly bumps. They are in the neighborhood of 0.005" proud. I think you are spot-on with the cause, this bike sat in the Houston, Tx area for at least 10 years. It looks to me that the layers of different material are separating and pushing the top layer up. Just like having rust under your paint. Actually they all appear in areas that show no witness marks from wear. Funny to see just how out of round these bearings are. My concerns about reuse are twofold. Lack of oil pressure, and potential that the bumps cut loose and float around in the oil.

newOld_kz1000 wrote:

Hi, have not done a build like this but would like to at some point -- what $$ budget are you estimating for completing it (not the Hi-Po motor, just for finishing it with your 'streetable' motor)? I'm guessing $1000 to $2000 for finishing the bike 100% complete including bodywork, paint etc. (since you're a machinist and can do the work yourself). Meaning just on parts, not any labor. Close?

NewOld,
I think you are close, and I'm guessing close to the $2000 mark. What I have got so far is $400 for the KZ, and $260 for a donor GSXR. I expect to re-coup 100% of that $260 since I have a good radiator, cooling fan, subframe, most of the plastics, exhaust, motor(core), and a rough gas tank that I can sell. I'm using a 78 KZ750 tank that I got off Ebay for $50. I'll be painting so lets say $300 for supplies. $250 for various gaskets, and seals, I really want that black Kerker so $525 Yikes! New tires $300. Just that stuff adds up to $2085, but again I suspect that, in time, that GSXR will pay for itself. I will also have some extra KZ parts that will put some money to the good. I'm sure that those funds will go into things like electronic ignition, new pistons, etc.

This is a sweet build!

I almost got into a similar build a year ago, but changed my mind. It looks like you might change my mind back again!

Keep it goin'!! :laugh: :laugh:

testarossa wrote:

newOld_kz1000 wrote:

Hi, have not done a build like this but would like to at some point -- what $$ budget are you estimating for completing it (not the Hi-Po motor, just for finishing it with your 'streetable' motor)? I'm guessing $1000 to $2000 for finishing the bike 100% complete including bodywork, paint etc. (since you're a machinist and can do the work yourself). Meaning just on parts, not any labor. Close?

NewOld,
I think you are close, and I'm guessing close to the $2000 mark. What I have got so far is $400 for the KZ, and $260 for a donor GSXR. I expect to re-coup 100% of that $260 since I have a good radiator, cooling fan, subframe, most of the plastics, exhaust, motor(core), and a rough gas tank that I can sell. I'm using a 78 KZ750 tank that I got off Ebay for $50. I'll be painting so lets say $300 for supplies. $250 for various gaskets, and seals, I really want that black Kerker so $525 Yikes! New tires $300. Just that stuff adds up to $2085, but again I suspect that, in time, that GSXR will pay for itself. I will also have some extra KZ parts that will put some money to the good. I'm sure that those funds will go into things like electronic ignition, new pistons, etc.

Sounds reasonable, encouraging too, with the part out of the donor bike. Would love to hear the final outlay. And good luck to you, everyone here can help! Pictures welcomed too, it's very informative for those of us thinking about a build in the future...thanks. I only wish I had your machinist skills, that part I'll have to tackle when/if I decide to do it.

Monday update here. I sucked it up and finished tearing the engine down today. Pleased to say that everything in there looked good. Did have some funky thick black oil in the bottom of the pan, but zero sludge deposits anywhere. Did have two of the case bolts break off, but I'm actually surprised that there weren't more. Also, looks like the alternator rotor spun on the crankshaft. The end of the crank was slightly galled and that bugger was a bear to remove. I need to get some pics of the hidden bolts to remove before you try to split the cases. I'll try to post these tomorrow.







You will notice that the number one piston has been removed from the rod. This was necessary to remove the crankshaft assembly from the upper case half. All of the other pistons came out easily. I suggest that you remove this piston before you split the cases. BTW to remove the piston just pull the circlip out at the end of the wristpin and gently tap the wristpin out from the other side with a brass punch.

One more quick pointer here for removing those pesky phillips head cover screws.

Here's one of my funky clutch cover screws.



Get out your #3 phillips head screwdriver and your hammer.





Put that screwdriver in place and give 'er a couple of good wacks to get it seated real nice.



This does two things for you 1)the impact can help loosen seized threads, and 2) it swages the head of the screw to fit the tip of your screwdriver exactly.

Now without moving the screwdriver, get both hands on there, lean your weight on that screwdriver, and "Man-Up."
Remember lefty-loosey.

This really helps with munged screw heads and seized threads.
Also helps if you can hit it with some penatrating oil the day before you actually try to un-screw it.

testarossa wrote:

OMR I had considered your idea about the steering stem, but I was concerned about the KZ stem being welded into the lower clamp. So did you grind out the weld, and then press out the stem? Which direction did the stem press out? This sleeve would def. be easier to turn than a whole new stem. A little less "Government Work" would be easier to get approved by the Boss-man.

Plummen, I must know what your comment was about my bearing pic. I have two guesses 1.)No comment-if you can't say anything nice... 2.)Hit quote button, then pass out as the unconscious finger left clicks the Submit button. I'm really dissapointed about those bearings, b/c other than those bumps, I'd reuse them. And those little buggers are kinda expensive.

Anyways, I didn't make too much progress today. Just popped off the jugs, and I'm pleased with the state of the union of the cylinder department. I also gave my work bench a nice protective coating of 10w40. I was forced to go for a ride on the zx-10r today since the weather was soo nice in Houston today.

Here's a couple of pics for you pic hounds:

i got in a hurry and screwed up! :laugh: its in the middle of your post,it basically says ive seen worse so dont worry.just clean em up

An impact driver works very well. Not to mention no risk of injury.
The Phillip head screws on these older Jap bikes are different than what most of you have for screwdrivers. With the correct screwdriver bit, there will be no marring of the screw head.
Your pointer about setting the screwdriver first is good though. You are correct in that the force will break the corrosion formed by years of aluminum to steel. When reassembling, I use a little bit of Bel Ray assembly lube. It fills in all possible air gaps and prevents future corrosion. Don't worry about the bolts loosening up in time. If you use just a little, you won't have a problem.

gershom wrote:

An impact driver works very well. Not to mention no risk of injury.
The Phillip head screws on these older Jap bikes are different than what most of you have for screwdrivers. With the correct screwdriver bit, there will be no marring of the screw head.
Your pointer about setting the screwdriver first is good though. You are correct in that the force will break the corrosion formed by years of aluminum to steel. When reassembling, I use a little bit of Bel Ray assembly lube. It fills in all possible air gaps and prevents future corrosion. Don't worry about the bolts loosening up in time. If you use just a little, you won't have a problem.

Good point about the impact driver, but I don't have one, so you get the poor man's version. Also good point about the assembly lube. If you do nothing to steel screws in aluminum housings, then you will suffer the ravages of galvanic corrosion.

As to the different Phillips heads from the Japanese you are also correct, but I don't think these fasteners are on my bike. JIS (Japanese Industrial Standard) screws do not have the torque-limiting tapers inside the "cross." They should also be marked with a dot outside the cross as in this example:



You will also notice the lack of a radius on the corners in the picture.

I believe that my fasteners are regular phillips head as they have no dot and they do have the radius on the corners. I have no idea if they are correct for the bike or not since I have only owned the bike for one year. Who knows what the PO did with the bike. My guess is that these fasteners are correct as my bike was built in the USA. Here's a pic of the best three fasteners I could find from my bike:



Plummen-I see it now. Usually I just blaze past the quote since I wrote the quoted section. That comment was hiding in plain sight. Would you still use those bearings if I told you that the light colored dots in the pictures are bumps that are 0.005" tall? Its really amazing to see just how much of those cam bearings never touched the cam journal.

Tomorrow's lesson will be how to tear down an upside down fork for those that are doing the conversion like me.

As promised here is the disassembly of one of the fork legs from my donor 1995 GSXR 750. This should be basically the same for any modern upside down fork. Generally speaking these forks need seals and dust covers replaced either from age or from the PO's tendancy to wheelie the bike alot. Unfortunatly, you have to tear the forks completly apart to get the seals out, and this does require special tools - usually.

Let me start with my disclaimer: I post this information for reference only. Please note that these forks have coil springs under compression, which can store a significant amount of potential energy. Anyone who attempts this himself must do so, knowing that a certain risk in inherent in this type of repair. Furthermore, I accept no responsibility for any personal injury or property damage that anyone incurs by attemting this repair themselfs.

I apologise in advance as this post will, necessarily, be lengthy with many pictures. I am assuming that you know how to get the front fork legs out of the triple trees, or you have no business trying this one.



Ok, step 1)
Make sure that you have all of your needed tools at hand, or at least a helper who knows were in the hell all of this stuff will be. I started with three crescent wrenches, (I'll explain why as I go) my trusty workbench with vise, floor jack, various wood scraps to block things up, I used a spanner socket attachment, but you would do well to have a proper fork spring compressor, small flat blade screwdriver, and a scraper.

Step 2)
Chuck that fork leg in the vise using some wood scraps to pad the vise jaws, or you'll do some real damage here. Tighten the vise carefully. Not too tight or you'll bend the outer tube. It's a thin wall aluminum tube.



Step 3)
Unscrew the preload adjuster (the smaller hex on top of the fork.) It should stop against a circlip at the top. Don't try to remove it, just back it all the way off. This removes as much tension on the spring as possible.



Step 4)
Now get out your big wrench and undo the big hex which will unscrew the whole top cap from the fork tube.



Once it comes loose, you should be able to slide the cap up until you see this:



Those holes in the metal sleeve are where you need to hook your sping compressor up to. You should really have a spring compressor here b/c most of the newer forks will have a plasic sleeve here. I am a cheapskate, and I get away with it here since my sleeve is steel.


Step 5)
Compress the spring to expose the jamb-nut pair on the end of the dampner rod. THIS IS THE DANGEROUS PART! I did it by placing my spanner socket hook in the vise. Once hooked through the hole in the steel sleeve, the spring is compressed from the bottom of the fork leg by my floor jack.



Please note that everything needs to be in a straight line, or that spring will shoot your jack out the side. Its best to keep a hand on the tube to keep it all lined up. Now jack that baby up until you see those jamb-nuts.



Here's where you really need to have those two crescent wrenches handy. The reason I used crescent wrenches is that I had no prior knowledge of what size the nuts would be. This is no time to be fumbling to find the correct wrench.



Now undo the jamb-nuts and remove the top cap. This would really be easier with the proper spring compressor, as it should have a clip to hold back the spring while you work.

Next, carefully release the jack or compressor to remove the spring pressure. Now you are safe again.

Now for part two of fork disassembly:

Step 6)
Dump out as much of that nasty oil as you can. Work the dampner rod back and forth and this will help. You can't get it all here but every bit helps.

Step 7)
Remove the sleeve and the coil spring, being sure to keep this stuff in order. Helps to do one leg at a time, then you have the other as reference. They aren't always exactly the same, but most are.



Step
Unscrew the dampner from the bottom of the fork leg. This one took a 8mm allen wrench inserted through the bottom. Sometimes you have to use something to jamb the dampner from the top to get it to unscrew. Sometimes you can use an impact gun to undo the banjo bolt. I got lucky with this one. It was tight, but unscrewed without holding the dampner at all.





Step 9)
Now pry out the outer dust seal using a scraper with a fairly wide blade. (1") Be careful not to scratch that lower fork leg.






Step 10)

Remove the circlip with the small flat screwdriver.



Step 11)
Carefully pull the upper, and lower fork legs apart. This may require some force since the seal is a light press fit in the upper fork leg.



Step 12)
Clean up everything as you are likely quite oily by now.

Step 13)
Have a beer! You are halfway to saving yourself $250!

testarossa wrote:

OMR I had considered your idea about the steering stem, but I was concerned about the KZ stem being welded into the lower clamp. So did you grind out the weld, and then press out the stem? Which direction did the stem press out? This sleeve would def. be easier to turn than a whole new stem. A little less "Government Work" would be easier to get approved by the Boss-man.

Grind the weld off the bottom and press the stem out from the bottom. take the gxr stem chuck it in the lathe and drill a hole in the end the same size as the KZ stems bottom O.D. now cut the end off and u have a sleeve for the bottom of the KZ stem. Press the stem into the sleeve then press the sleeve and new stem back into the GSXR tree. Done. i drilled and bolted through all 3 pieces for piece of mind.
Now make new steering stops.
For the gauges , u can cut the gauge tabs off the KZ top tree and weld them on the GXSR tree.
Now just hunt up some risers on ebay. I used some off an old yz125 I think?
Here is a link to my project.
kzrider.com/index.php?option=com_kunena&...w&catid=11&id=103381

look through the projects, there are lots of guys who have documented this for your help. OMR did a very nice right up.
As for the cam bearings. if they are bent up as u say, u may be able to find new 1's on ebay, or in the for sale section hear.
If they are not to bad , u could rap emery paper around the cam journal and rotate the bearing around it to sand off the bumps. but in the end, if u are not happy with these, get some more. u should have no trouble finding good used 1's . they dont wear out.