cylinder block mill

And don't forget to watch valve to piston, valve to valve, and head to piston clearances :laugh:

dshelly wrote:

why don't you just bore it and get some 10.25:1 or 12.0:1 pistons. Then run bigger valves and port the head? That will make a huge difference. If you Mill the Head it's gone forever. Otherwise you can always go back down on compression by just a piston swap.

Or a thicker gasket

I can’t give you advice on the optimum compression ratio regarding head milling, as I am not an engineer as such, just advice from life experience….

I have GS1000s with a Yoshimura 1085 big bore kit (the real yoshi deal not just a muffler ). It had a blown head gasket one time, nothing major just poor quality gasket and as the kit was fairly new it should have been pretty simple even told this mechanic “don’t do any thing to it just replace the gasket and seal it up”.. I thought.
When I went to pick it up, the bill (in 1991) came to $875 WTF!
“We do things properly here,” said the mechanic….:dry:

Anyway to cut a long story short… MY GOD! I have never seen anything blow so much smoke, worked it out to go through something like 500ml of oil every 300ks and god was it noisy…. again, WTF!

Reluctantly and with a lot of pressure from a friend I took it to another mechanic (heres a tip: find a mechanic where 70% or more of his work is fixing other mechanics stuff ups, that’s a good mechanic… plus being a drag racer helps also), those “we do things properly” guys really did a number on my motor. They had milled the head down so much (it already was when the kit was fitted…. wankers!) that the piston was slapping against the head and also ground the piston ring edges flat…why?
The new mechanic told me “you are lucky it didn’t smash a piston or rip out a ring”…

Ahh, That’s why!

Point is…. all was not lost he skimmed the top off the piston, cleaned the head up, put on an aftermarket thicker gasket and machined out the ring landings for Arais rings (cheaper than yoshi, $18 a set as apposed to $42) now after an extra $1200 and some 5000ks later, this thing kicks like it should!


Don’t think that things are stuffed if there is a mistake made I.e. mill too much off the head… as there are always alternatives!

subby wrote:

I can’t give you advice on the optimum compression ratio regarding head milling, as I am not an engineer as such, just advice from life experience….

I have GS1000s with a Yoshimura 1085 big bore kit (the real yoshi deal not just a muffler ). It had a blown head gasket one time, nothing major just poor quality gasket and as the kit was fairly new it should have been pretty simple even told this mechanic “don’t do any thing to it just replace the gasket and seal it up”.. I thought.
When I went to pick it up, the bill (in 1991) came to $875 WTF!
“We do things properly here,” said the mechanic….:dry:

Anyway to cut a long story short… MY GOD! I have never seen anything blow so much smoke, worked it out to go through something like 500ml of oil every 300ks and god was it noisy…. again, WTF!

Reluctantly and with a lot of pressure from a friend I took it to another mechanic (heres a tip: find a mechanic where 70% or more of his work is fixing other mechanics stuff ups, that’s a good mechanic… plus being a drag racer helps also), those “we do things properly” guys really did a number on my motor. They had milled the head down so much (it already was when the kit was fitted…. wankers!) that the piston was slapping against the head and also ground the piston ring edges flat…why?
The new mechanic told me “you are lucky it didn’t smash a piston or rip out a ring”…

Ahh, That’s why!

Point is…. all was not lost he skimmed the top off the piston, cleaned the head up, put on an aftermarket thicker gasket and machined out the ring landings for Arais rings (cheaper than yoshi, $18 a set as apposed to $42) now after an extra $1200 and some 5000ks later, this thing kicks like it should!

You heard the sound of the pistons hitting the head and didn't record it :ohmy: That was a good scare story to hear. It's like the Friday the 13th warning. What color and what type is your bicycle So I know it's you and can give the quarter without having to listen to the hype :woohoo:


Don’t think that things are stuffed if there is a mistake made I.e. mill too much off the head… as there are always alternatives!

Well I've heard enough to know that theres
secrets here within. There must be another conspiracy going on. The iptimum squish ocurrs at blow up :laugh: Hit the garage at midnight two days ago and tore that engine down, lifted it up with my mighty strength onto the bench and when u loctite your cam bolts up high on the threads like I did cuz..... They were tight coming out! everything looks good cept second gear combo was worn rounded and the bushing seemed loose. Im gonna tear the 1000 motor apart and check whats in that one. My 1015cc kit has around 12thousnad miles on it. The tops of the pistons looked alot smaller than the bore! I put ten thou feeler gages and it fell in like ( who should I pic on ), didn't dare try any more guages! Machine shop bored them crooked for me years back and I just can't pretend anymore that the work was top notch. So I'm pulling my sponsorship( Won't eat any more of their free cookies on the counter). My little wiseco's are so dinky! They shhrunnkk! :ohmy: Could I build the surface up with jb weld? :woohoo: :blink: I didn't check the shifting acutation before taking it apart. I'm not confident the gears are being pushed together like the should be. I'm swapping trannies :woohoo: It's gonna be fun to see what this new tranny can do! Once the head blows off that's all I'll have left! Anyone want a countershafy nut that was forced over a tack weld? It didn't do so well. Little over a week and I'm sending the head in, yeah right. Right. And it's gonna work cuz I am the man who can. If you come see me working on this bike never mind the caution tape aroung the yard, it's mandated by the city council. They softened the blow by telling me it's so none of your secrets will get out...it's not a transformer, once again the smoke seems to be coming from my garage roof. Piston falls to rest in school playground, children laugh at it
's puny size! Being a 1015 guy has it's down side. But things are looking up! Reflecting back to yesterday, I have a hell of a mess in the garage. And I like it that way! I'm taking pics as I go so I'll get them together one day and post away. YEAH RIGHT! WHATEVER MANN! Well see about that! OK OK! Give me some time. :side:

nads.com wrote:

subby wrote:

What color and what type is your bicycle So I know it's you and can give the quarter without having to listen to the hype :woohoo:


quote]

No need for the quarter, I don’t have any friends who care enough that’s why I’m on this forum…

Here are those numbers without the hype….endulge

Piston to head clearance is determined by rod material, mass of a piston and piston speed. Alloy rods require more than steel, extra 0.010. On drag motors, no less than 0.015… On long period racing engines, no less than 0.025. Most Japanese bikes get away with 0.030….

Piston to valve clearance depends on cam timing and valve train mass. The most common problem with broken valves is not from vertical clearance, but lack of radial clearance.

Piston to valve clearance (at TDC) on KZ should be .030 minimum cold.

Nads, start with the basics!

What is the technical definition of squish clearance? Where is it measured from (from what to what)? What is the differance between squish clearance, and total deck height?

How close can I get is .025 too close? The base gasket was super thin and aftermarket junk from the beginning. I'm going to assume deck height is jug to base no space. Solder will tell me piston height. I've got .050 on a old gasket. I looked at it and :woohoo: There ain't nothing wrong with it! It's broke in, nice shape to re-use.

I used red silicon aroung the stud holes and no o rings, same around the cam tunnel. It was all just solid. Must have helped to degrease it and wipe off the excess, that stuff held up good. I'm good on the valve end, measure that too. I should have measured it before I took it apart :laugh: SO I can go by valve clearance previously known. Not, I'm screwed. Bang. :blink: I figure If I have 10.25 and with the cams 280@.020 the mill amount is not going to be much to take it over 12.01, I can tell by the piston to valve clearance I can take .030 off that head and use it with the .050. Piston to valve can afford .030. clearance, it's been measured before :huh:

I'll measure it before I run it and get the total. This block is'nt going to settle, it's been there done that. I think I could even use sealer on the block, no damn gasket. I'm sick and tired of nursing old shit gaskets and cutting new ones that waste to dark resin on the aluminum. They burn up if they get over 100deg. :woohoo: Yeah that stuff.

The head studs scare me they look bouncy. Like weeeeeeeeeiiiiiirrrrrrr while the engine is running. NOt good! I think the center four could use some help. That to me is the center of mass. The end crank bolts and smaller case bolts ALL around need to be good and solid, the way i run my cam timing the motor is smooth at high rpm just not perfect. It's more the flow action in and out that makes the motor suffer vibrations due to the hold up through the head. Ignition timing can bring on a good strong pulling motor out of my bike and would be good for low gears and an attempted quarter. But. It's not the smoothest at high rpm. I can back it off and it gets smoother the power band moves up and it accelerates effortlessly. None of that can be true because I have it apart :lol:

Basically what I'm doing now is raising the compression ratio to 180psi min. Then opening up the heads for more flow. Then Putting on some carbs at least six mm larger 28mm. Then Ill degree the cams for record ( check the deck height) take the retard on the intake cam and run with it. One way or another I'm gonna make those cams make as much high rpm power as they can. It'll take me awhile but the work needing to be done will never slow me down. The motor that is. I always moniter clearances so I know where I'm at before I run it. Cuz I know I'm going to run it. Hard. As long as it takes it in stride it'll do it all day long. Long as there is oil pressure. Don't touch the pump or think about it is one of my rules. I just know it's working and leave it to work, how would like someone getting in the way when your trying to work? I'm just one of those guys that will never have an oil pump go out... We know who the oil pump guys are. We respect them all for taking the fall. BUT. I'm going to find out If this head will be the solid component of output for this motor. I figure if the flow reaches that of the gpz I've got a chance to make things work in my world. The fit, the finish. THE RIDE. Park it, look back... Every time you see something you cut it off. Pretty soon it better be looking good or your in trouble. I'll have this bike done before the snow melts. Heck I'll be happy just looking at then clean work. I can't be missing gears anymore, I won't have the clearance. Problem solved, I don't miss gears. It won't be popping out of second anymore., I don't need to be missing any gears, that's sloppy. I can picture myself going from first to 3rd if I wanted I could do this with the front wheel off the ground and the throttle near wide open through it all. Kz's balance well to me. If you got the easy power, I ride my bike for one reason, to have fun. The bike has to have modern day performance and look. It has to have individual, unique charactor such that only one person could create. I made my bike to be clean. And it paid off. The set of the bike represents the way and the angle that I take on life. :woohoo: And I don't even know how that happened. :huh: