Split Cases and replace parts for the F^@$ of It...

Hey all,

Well received an ass chewing last night from my longtime friend Dennis (motorcyclerecyclers702@yahoo.com)on why I'm not splitting the cases and replacing the bearings, seals, checking the shift forks, gears etc...

Since I don't know the history of this bike on how it was ridden or maintained (image says not so well) I know he's right but damn it.... This may be a little out of my experience... Not to mention special tools required. :blink:

So my question to all of you is the following.

Get off my lazy ass and just friggin do it (for piece of mind over nothing else) or these old KZ's are built like a train and should be ok...

How many of you have had issues after upgrading to 1015cc & .365 lift cams or higher?

Meaning, new & higher compressions caused severe lower end problems....

What kind of problems can I expect in getting these bearings out? Special tools required. I've read where some of you had freeze (wifes freezer :whistle: wont go over well) then heat etc...

I'll have to get out the shop manual and start pricing these components... Damn it.... I know he;'s right and if I don;t and this blows up in my face I'll never here the end of it...

Now I know most of you are going to agree with my old friend (actually I do as well) but I'd like to hear some experiences of what others have encountered in not following this advice...

I know, I know, split the damn cases you old bastard...

Thanks,

Old Man Rock

I'm not real mechanically smart, but I tend to want to take the path of least resistance and not court trouble. In other words, if it ain't broke, don't fix it. Get it running good, you may not have a problem. Everything I've heard is the bottom end of these motors are pretty durable.

This may be a good idea if you're adding power with the big bore kit though. I don't know how much more that would stress the bottome end.

Sorry not to be more helpful. Good luck whatever you decide.

Are you going to keep it?????
Has to be my first Question.

As you said, you know all to well what happens when the upgrades arrant done.

Bearings, I don't worry much about them. That being said.
If you don't do the crank + cylinder studs oil leaks
and blown head gaskets are sure to follow.
Fix it and keep it. Clean it up and sell it? HUMMMM
If it was mine Id fix it either way.

Although, We all know someone who knows it all
and would buy that bad Kaw. And then say,
I got that old man rock good on this one. Sell it to that guy.

Good Luck
XENU

If you don't do the crank + cylinder studs oil leaks and blown head gaskets are sure to follow.

Neither of these (oil leaks, knocks, smoke etc...) when orginally purchased and started seem to be an issue. Same time, this is all stock 900 OEM components.

Do the crank, meaning get it welded?

Cylinder studs meaning HEAVY DUTY HEAT TREATED CYLINDER STUDS as such from APE?

What about HEAVY DUTY MAIN BEARING STUDS?

As for the bearings, well hell If I already have this all apart I should just replace for the hell of it...

See what I mean, might as well replace every damn thing...
:woohoo: :blink: :woohoo: :blink: $$$$$$$$... hahahahaha!

She's going to be a keeper for sure for I have waited 30 years for this KZ900... :pinch:

Thanks, much appreciated.

Old Man Rock

omr take it from a fellow who has just had his engine out twice in the last three weeks .while kneeling beside the engine where you are checking the countershaft sprocket with the engine in neutral roll the countershaft through and listen to the transmission.there is one ball bearing behind the cover that is behind your countershaft sprocket,on the other end of the shaft is a needle bearing.behind the clutch basket is another ball bearing and a needle bearing on the opposite end.if they are rough you will both feel and hear the noise.if they roll through smooth your tranny is prolly fine.this is not like an inserted bearing motor,i.e. you do a top end and spin the rod bearings.how did the oil look?were there metal chunks in it?if you don't here any tell tale noises,i might suggest to fire it up and listen for noises and see how she sounds and go from there.you can always roll the motor back out and split the cases then.there are no "special"tools required and nothing jumps out at you ;-}.you can leave the top end intact and just pull the bottom cases and all is exposed.it is your bike tho and you need to do whatever gives you that warm comfy feeling.you can also do the top end in the bike if the studs need replaced,so you can do it piece meal or whole hog it's your baby!hth
leon

You will only have to do it once, my 76 900 was sleeved to 1105 30 years ago. Its got 10.25 pistons, a ported head, 395 lift 260/260 cams, Kerker pipe, Dyna ignition & coils and 29mm smoothbores. Still hauls after 30 years and you dont have to be a 16 year old gymnist to ride it. Lost in the 70's:laugh:

Shaft seems fine, no noise, slop or side to side movement. Oil is dark but no metal shavings what so ever. Under or above I didn't have any oil leaks.

The head looks normal, expected carbon build up after 30 years but nothing out of the ordinary as far as I can tell. Dark brown almost black carbon color, dried and not oily or burnt oil on the valves.

Head will be cleaned (carbon), valves checked and replaced if necessary but definately cleaned of carbon, .365 lift CAMS w/new springs, new seals and guides is the game plan.

All 4 spark Plugs are normal brown wear, no oil or white burning found.

Unfortunately I can't start the motor at this time (All apart). New Wiseco 1015cc kit w/cylinder on it's way.

I was thinking get this old girl running and if need be, pull the motor after running to see if I truly have any issues in the lower end. Same time, the last thing I want to do under this concept though is end up doing some major damage for that would truly bum me out...

Banshee, was this "omr take it from a fellow who has just had his engine out twice in the last three weeks " due to not splitting the cases and getting to it? Damage report?

mtkawboy, "You will only have to do it once" translating into get off my ass, do it now and never have to worry about it again?

Thanks guys,

OMR

So, Your going to keep it. COOL
If you are going to lev it stock let it be.
Clean it up and ride the ---- out of it. those motors
are good for 80k easy. With nothing more then good
maintenance.

Now if you want to hop it up. I would suggest you find
a second motor do all the upgrades on that. Then all
you have to do is a simple engine swap.
You can find motors everywhere if you are looking for one. lots already have some good stuff in it, they just
need to be finished.

Now days a stock untouched 900 motor (to me) is worth
more then a motor that some guy says thats a 1075
You can't tell what's in there till you take it apart.
And it a good bet it has a blow-en head gasket and the guy doesn't know how to fix it, or he has fixed it three
times. Why you might ask? Because he didn't or doesn't
wont to do the upgrades for a high com. motor.

I have built several 900/1000 motors over the years mostly for other people.
The ones that were willing to spend the extra bucks
Get A motors that will go fast and be DEPENDABLE.
Others would only pay for pistons + cams. You can
count on the latter to come back and say it's leaking
oil out the head gasket, or it blue the head gasket, or
the cam chain broke and trashed the motor.
The list just go's on + on.
Spend the money and do it RIGHT the first time.........

OK im of my soap now.
No offense implied or implicated

XENU
ps the last motor I built for my self. (drag motor)
the only bearing I replaced were the out put shaft
and the clutch pusher all others have around
500 passes on them. as I said don't sweat the bearings.

FastKaw1, yes correct for the timing chain as for my old friend did last night as well, replace the chain and timing sprockets, guides, tensioner etc...

Damn it, damn it, damn it...

Ok, you've all convinced me, get off my lazy old ass and split her open... Crap, have to remove it out of the frame, once again... At least the top end is off.

At least I'll be able to sleep at night...

Friggin old bitch better be worth it... hahahahaha

Thanks guys,

OMR

When all is said and done please let us know how
it went.
Smart Move. And Good Luck

XENU

One part you might think about replacing is the bushing, for lack of a better term, where the clutch pushrod comes through the left side of the case. I have one bike where the bushing is worn which caused the pushrod to wear, eventually breaking which made me pull the output drive off the left side to replace it and fish out the broken end. In a shaft drive this job is a PITA. It is the only bike of the ones I have/had where this problem came up but as long as you have it apart......

i pulled my motor to replace the bearing behind my countershaft sprocket,because i could here it clicking the balls together when i was down there measuring to build my offset countershaft sprocket.the race had busted through the locating ring groove and the cage had come apart,freak deal(been that way for over ten years)i mistakingly ordered the doublerow bearing for the input shaft.it will install on the output shaft but hangs out of the case far enough to impede the shift mechanism.which i did not check until the engine was re-installed in the bike so therefore i had to pull the engine and r&r the bearing and re-install the engine.
i don't believe i would split my cases being as how it all sounds good and smooth,there is not that much there,some ape heavy duty studs might be a sound bet with your higher compression ratio tho.