J head forensics. Fix it or trash it.

So my social skills suck. I haven't introduced myself and I'm asking for help. Oh well.

A few years ago I got a non-running KZ1100A. I got it home and got it to run, but the more I looked it over the more PO horrors I discovered. It definitely had a hard life.

Well recently I thought I should get rid of it. Maybe part it out. So I looked at Ebay to see if parts were selling. Bought another engine. Damn Evilbay. Well that engine has issues too. So why stop there, bought another head.

Beginning to see a trend here. It needs to stop. No hope for my head, but maybe you guys can help me figure out what I've got.

So...
2 bottom ends condition unknown, assumed okay.
3 cylinders and pistons 2 of them about half worn out, 1 prolly a candidate for sleeves.
3 heads that have me going round and round.

I'd just like to get one engine running good enough to use up that second half of the cylinder life. Maybe save the rest for later or trash it. No money to do anything cool.



J HEAD #1: The original and probably the best one. Don't it figure!
Pretty much Zero shim clearance.
PO single angle valve seat grind job, prolly 3mm contact..
Valve stems ground, 2 at the limit.
Guides got about .005" or so wiggle, good enough.
4 or 5 striped cap bolts
Bearings not great visually, prolly dirty oil ... do I care?
Cam looks okay.
3 busted fins.
1 stripped spark plug.
All fixable. Is this about your average head?

J HEAD #2: from the second engine. I can be such a sucker!
Would need a valve job, but the valve stems are a bit better.
Guides okay again.
Plugs okay and fins good.
BUT this PO stripped just about every M6 bolt on it, cam caps, cam cover, even the ones on each end to the cylinders. Then tried some 1/4 bolts and stripped them. And then... put a 5/16 in place of a dowel and stripped that too. And the kicker, busted the cam cap in half.
AND THEN ran the thing with swarf in the oil and scored the cam at the bearings. (I'm guessing, but seems logical.) Might polish out?

Can you fix the threads when it is stripped out to the size of the dowel?
What does a line bore cost if you weld or replace that busted cap?
Trash?



J Head #3: This one surprised me, I thought it would be stock.
2 angle grind on the valves themselves. I'll be damned that's a new one for this beginner. Cool.
K435 cams, not so cool.
Titanium retainers and Spring kit? Missing buckets.
Ported. Juries out.
Some heli coiled cap bolts.
This thing got hot. Evidence of aluminum in exhaust ports, and stuck to valves. One intake valve and seat dented by something hard.
Aluminum eroded at head gasket edge, and porous looking in combustion chamber.

Must have been spectacular when this thing blew.

Is the alloy in that chamber a problem?
Skim it to get the head gasket to seal? 60 thou or so? Compression increase?
Too much port work for 1075cc and BS34 carbs??? Velocity - Vacuum issues?
Worry about overheated valves???
Any value in those cams?
Trash?





A half worn out 1075 with 9-9.5 compression and BS34s would be sweet.
Dream on?

Measure the Cylinder Bore, and see if it can be honed within service specification. If that's the case than you line up...

4* 13008-5037 Std Ring Set

4* 13002-1013 Wrist Pins

4* 92033-1054 Circlips

All available from Kawasaki.

I'd choose J-Head No# 1 probably and Timesert/Helicoil the Cam Cap/Spark Plug holes. Than I'd box it up and send it to Larry C (Member Here) for a Standard Valve Job, and inspect the Valve Guides. Send your Valves from No.#2 Cylinder Head along with the #1 head.

CLICK---> Repair/Timeserts

A Top End Gasket set is about $80.00 almost anywhere.

Kraz1 wrote: I'd choose J-Head No# 1

I agree that is prolly the wise choice. I think the bores are good to go as is. Maybe a light hone at most. Haven't disassembled the piston-rods. Things measure about half life.

I can't stop dreaming about the ported head though. I suspect more trouble than it is worth... just not sure. No experience.

Check your pm box

rstar45 wrote: So my social skills suck. I haven't introduced myself and I'm asking for help. Oh well.

A few years ago I got a non-running KZ1100A. I got it home and got it to run, but the more I looked it over the more PO horrors I discovered. It definitely had a hard life.

Well recently I thought I should get rid of it. Maybe part it out. So I looked at Ebay to see if parts were selling. Bought another engine. Damn Evilbay. Well that engine has issues too. So why stop there, bought another head.

Beginning to see a trend here. It needs to stop. No hope for my head, but maybe you guys can help me figure out what I've got.

So...
2 bottom ends condition unknown, assumed okay.
3 cylinders and pistons 2 of them about half worn out, 1 prolly a candidate for sleeves.
3 heads that have me going round and round.

I'd just like to get one engine running good enough to use up that second half of the cylinder life. Maybe save the rest for later or trash it. No money to do anything cool.

J HEAD #1: The original and probably the best one. Don't it figure!
Pretty much Zero shim clearance.
PO single angle valve seat grind job, prolly 3mm contact..
Valve stems ground, 2 at the limit.
Guides got about .005" or so wiggle, good enough.
4 or 5 striped cap bolts
Bearings not great visually, prolly dirty oil ... do I care?
Cam looks okay.
3 busted fins.
1 stripped spark plug.
All fixable. Is this about your average head?

J HEAD #2: from the second engine. I can be such a sucker!
Would need a valve job, but the valve stems are a bit better.
Guides okay again.
Plugs okay and fins good.
BUT this PO stripped just about every M6 bolt on it, cam caps, cam cover, even the ones on each end to the cylinders. Then tried some 1/4 bolts and stripped them. And then... put a 5/16 in place of a dowel and stripped that too. And the kicker, busted the cam cap in half.
AND THEN ran the thing with swarf in the oil and scored the cam at the bearings. (I'm guessing, but seems logical.) Might polish out?

Can you fix the threads when it is stripped out to the size of the dowel?
What does a line bore cost if you weld or replace that busted cap?
Trash?

J Head #3: This one surprised me, I thought it would be stock.
2 angle grind on the valves themselves. I'll be damned that's a new one for this beginner. Cool.
K435 cams, not so cool.
Titanium retainers and Spring kit? Missing buckets.
Ported. Juries out.
Some heli coiled cap bolts.
This thing got hot. Evidence of aluminum in exhaust ports, and stuck to valves. One intake valve and seat dented by something hard.
Aluminum eroded at head gasket edge, and porous looking in combustion chamber.

Must have been spectacular when this thing blew.

Is the alloy in that chamber a problem?
Skim it to get the head gasket to seal? 60 thou or so? Compression increase?
Too much port work for 1075cc and BS34 carbs??? Velocity - Vacuum issues?
Worry about overheated valves???
Any value in those cams?
Trash?

A half worn out 1075 with 9-9.5 compression and BS34s would be sweet.
Dream on?

Cams are worth $150 all day long if they're good.

.060" off the deck is a far cry from skim....

Hi Larry, you da man... or at least one of them. :laugh:

First... ya think the alloy is OK ? How would you know, test it?
See I'm a carpenter. If it was wood I could say "Nah man that boards no good, it's got dry rot." But I don't know metal. What could reaching melting point do to the alloy? Should I bake it? stuff like that is a mystery to me.

Then... (ported) it still might not be right for me at this time, but maybe some other build?

So .060" ... Problems? Valve clearance? Squish band? cam chain?
Weld it first then skim it?

Melt it down for casting lawn ornaments?

One option I keep thinking about is to just make something run for now and hold back the better components (if I have any) for some future build when the finances are better.

There would still be a limit to how far I would go. I'm pretty sure I don't have the balls to take advantage of a big block.

Course a guy could buy now and pay later... the American way you know.

Is a J block cylinder the same as the earlier KZ cylinder so the max bore would be ____?
I've read Larry's FAQ, but I'm confused regarding models.

Have you guys seen these pistons? Chiba Japan... WTF

Comments on Cometic gaskets?

1170 is max bore with stock sleeves

I would probably stay away from cheap knock off pistons.

That looks like some sort of 1170 kit with cheap cast pistons,never heard of them.