Do I have to punch my cylinder?

[grayracer513]

You build your engines your way, I'll build mine the way I did the last 4 or 5 Hundred.

[Shawn_Mc]

That's some of the worst advice I've ever seen in print. All lubricated parts should be pre-lubed on assembly, piston an rings included. In 35 years as a professional mechanic, I have never assembled one top end dry, and none of them have failed to seat properly.

Ya think so huh?

What's "properly"?

Pm Ron Hamp and ask how he assembles the top end on one of his AMA National 505 class winning stock bore and stroke 450's (that make well over 60 horsepower).

Or God rest his sole, Smokey Yunick on how to achieve a .3% leak down.

Thats 1 third of one percent, not 3%.

Back in the day we thought we were hot shit if we could get the leak down to 3 percent. Now youre nothing more than a back yard hack at 3.

Slathering them up is old school, but unless your using pale oil (and sparingly at that) your throwing away a ring seal you thought impossible.

Back in the day, motor oils weren't so good and you could get away with sliming everything up and still get a decent seal. But oils today are so damn effective now that they can prevent the ring from seating with the vigor that it could had you done it another way. Most competition engine builders now use Titanium Nitride powder dusted into the ring lands and thats it. Maybe a smear of something on the skirt.

Before you react all agro like, sit down and think about it. Stuff changes.

I've been taught: If you stop learning, you may as well just lay down and die...

[Wayward Son]

lets keep this thread to sharing methods and theorys.dont turn it into a flame war or i will shut it down.

agree to disagree at minimum,but be respectful of experience.

i build motorcycle motors daily for a living.

the piston,rings and cylider go together dry.my motors are proven winners and power makers.so i stick with my methods.

[FFRacing79]

Just a point to think about. And to verify my comments here, I have been personally involved with one of the top plating companies in the past.

Your Ball Hone, unless an expensive diamond or high silicon content hone, will NOT leave a crosshatch in your nicosil cylinder(It might appear to, but if you were to run your motor for even 10 minutes afterward, any crosshatch you thought you had would be gone!). All your basic auto parts store hone will do is break any "glaze" your cylinder might have. Once the glaze has been removed, it will show any remaining original crosshatch.

As an example, if you were to leave a standard ball hone run in a good quality nicosiled cylinder for say an hour, what you would have is one trashed ball hone and a cylinder that has lost NO nicosil and retains the same dimensions you started with.

As far as assembly lube, once you have cleaned your cylinder with ATF and the paper towel, the residual ATF is more than sufficient lube to run your motor. Excessively dousing the piston and cylinder with pre-mix or motor oil will only prolong breakin.

This is only my opinion, though learned from building hi-po professionally raced motors for many years and from rebuilding many(100s) of amateur raced motors as FFR.

I am not saying anyone elses procedures are wrong, just that they are not always the way I would do it. Tdub

[Wayward Son]

i agree on the atf.thats what i use to clean the cylinders as well.

[grayracer513]

Ya think so huh?

What's "properly"?

Properly is when it's done inside the first hour, uses no oil, and lasts. Dunking a piston in a bucket is certainly unnecessary, and won't accomplish anything that a few drops of oil won't do except to generate a lot of smoke. But unless someone can offer me a good explanation of why I should dry start a top end, I won't.

Besides, the oiling system will be on line in a few seconds anyway, so it seems to me that nothing is accomplished by dry starting except to run the risk of scoring damage on initial startup. The dry condition will be replaced fairly quickly by a normally lubricated one. I don't see how pre-oiling rings on assembly could possibly prolong break-in more than the 90 seconds or so that it should take to arrive at a fairly normal running condition It never has for me), but it certainly seems like a good way to avoid trouble.

[Wayward Son]

the goal is to keep the oil off the ring faces.

your most certianly correct about the oil jet spraying the piston and cylinder immediately.thats why oiling up the piston is not needed.thats also why the "dry start up" you fear isnt possible either.

your method works for you.but that doesnt make other methods wrong.

[DigilubeJay]

With all new parts including quality, precision bearings, there will be a mismatch of sufaces immediately. And probably an even greater mismatch of surface with the rings, as the spring action of the ring itself provides pressure and increases the coefficient of friction.

These surfaces will wear at each other no matter what, once the motor is turned over.

The severity of this wearing process is totally dependant on the surface preperation.

This is all at the microscopic level. And the little hills and valleys (or asperities) of the surfaces when new, are protruding far enough (in ALL cases) that a simple fluid film cannot keep them seperated, and as a result they get sheard off.

It's been recognized by the auto industry that once a motor has been "broken in" that the only real severe situation that a running engine sees is during start-up and shut-off. At this time the fluid film provided by the oil and pump is comprimised. There must be some sort of barrier lubrication existing on the parts to protect during these severe conditions, or major wear will occur.

And for many years, auto engines did indeed wear at a high rate during extreme conditions...until there was more understanding of hydrodynamic and barrier type lubrication. Oil mfg's started concerning themselves more and more with the additives in the oil that will adhere to the metal surfaces in order to provide the much needed protection when the fluid film (hydrodynamic) regime failed to protect.

With advances in barrier lubrication technology, it was found that some additives can actually change the way the microscopic asperities react when they meet each other and shear one another away. Some of these additives can cause the molecules at the oxide layer to actually 'bend over' rather than completely shearing themselves off at the hilt.

It was found that this bending of the asperities, rather than a severe shearing off, allowed there to be less microwelding of the metal as it is being removed.

Moly does indeed serve as a great boundery lubricant, but it works differntly than the situation I have been describing.

There are other chemicals that are better at the sort of protection we are discussing.

And ATF is full of some of these types of chemicals that will reside at the oxide layer of the metal surface once applied, and will "come to life" so to speak, when they are needed.

Phosphorus and boron are two typical types of barrier adds that would be contained within an ATF (especially type F ATF). And that is why I suspect such good results when a person cleans the engine parts with ATF...because you aren't simply cleaning the little valleys out of debris, but you are also embedding those important additives into the oxide layer of the metals.

Slothering oil onto the surfaces does nothing, really..unless the oil is full of barrier adds that can be beneficial, because the fluid film of the oil itself is useless for the intital extreme conditions. Even if you used an oil that has barrier additives, as they all do today, the concentration of these additives is desinged to deposit themselves onto the surfaces during an extended run period. It takes a bit of time, from the fluid flowing around the parts, for any amount of these adds to collectively depost and adhere enough to be beneficial.

A rebuild fluid is designed specifically to add a concentration of these important chemicals to the metal surfaces, to provide a more uniform and tighter wear pattern at the microscopic level, without waiting for the flow of the engine oil to deposit such items. The flow of oil in an engine is "almost" immediate, but the concentration of the protective additives, in the small volume of oil, during that time is minimal, even with the most robust of engine oils.

The science behind what happens during a dry start-up and run is sound.

As is the science behind what happens with a chemoabsorbed barrier additive treated surface at start-up and run.

[ripntear]

lets keep this thread to sharing methods and theorys.dont turn it into a flame war or i will shut it down.

agree to disagree at minimum,but be respectful of experience.

i build motorcycle motors daily for a living.

the piston,rings and cylider go together dry.my motors are proven winners and power makers.so i stick with my methods.

Where's the "Flame War"? It's just 2 different opinions.

Why would you shut it down anyway? I don't see you having the justification to even make that comment.

[Wayward Son]

where did i say that it was a flame war?i was just asking that it not be turned into one.rather kept on track to a informative thread.

i dont have to justify my request.

i would and will shut i down if it had turned into a flame war.

this thread has alot of potential for good info.i would hate to see it ruined by bickering.

[ripntear]

Well,

It's a shame that grown people have to tip toe or be overly sensitive toward others when expressing there opinion or risk getting repremanded. There is not a single curse word in this thread and nothing offensive.

There are people on this site claiming to be "experts" then there are people who truly are experts. A professional and an expert are two totally different categories but can be both.

A "professional" does it for a living but may not be good at what they do.

An "expert" has the knowledge from experience to be an authority in their field and are highly respected. They have every right to comment on matters that pertain to their expertise. Some are more eloquent (sugar coat) in their approach, others may get straight to the point and call a spade a spade.

No one has to respect anyone for anything. Respect is earned not given.

[dunecj2a]

Well I started it because I have heard so many different opinions on what to do. This is my first 4 stroke and I dont have alot of $$$$ to throw around. I wanted to make sure I did it right. I don't have alot of faith in the dealers here in town. Plus everyone of them tells you something different. Here are some of the responses.

1. Yamaha only dealer - Don't do anything to the cylinder. Its Nikasil it needs no deglazing or honing. Oil the piston and your fine.

2. Yam/Suz/Pol. 10 dealer chain in AZ(Wal-Mart of bikes) - Hone it , oil it down and slap it together. No machine shop though we send it out, back in 3 days. ??

3. Non Specific shop - No matter what, bore it and replate it

4. Old school shop(does all the machine work localy) - Don't do anything, Wiseco doesn't recommend honing or deglazing. Its Nikasil so if its not damaged don't do anything. Oil down piston and go.

This last shop has alway been the one who has done any of my 2 stroke work. They always cleaned out my 2 stroke Nikasil cylinders, I stayed away from Wiseco back then though. All of my 2 strokes have been awsome and I really, really trust these old guys. But I know times change and thats what caused me to start this thread.

DirtRider has an article with Dan Dye showing how to do a top end on a YZ250F. He DOES NOT mention anything about honing or cleaning the cylinder. He DOES say to OIL the PISTON and RINGS before putting the jug back on. Seems like Chad Reed's and Team Yamaha's bikes work OK ?

I'm takin the advice I got from this thread and PM's.THANX AGAIN Real riders and people who work on there stuff. I'm honin my cylinder, oilin my piston and rings and hopefully I'll remember where all the bolts go?

I'll let you know if my bikes still runnin next week. Well hopefully I can get it started ?

[Wayward Son]

im sure you will be fine in how ever you do it.

[dunecj2a]

im sure you will be fine in how ever you do it.

[RADRick]

Ya think so huh?

What's "properly"?

Pm Ron Hamp and ask how he assembles the top end on one of his AMA National 505 class winning stock bore and stroke 450's (that make well over 60 horsepower).

Or God rest his sole, Smokey Yunick on how to achieve a .3% leak down.

Thats 1 third of one percent, not 3%.

Back in the day we thought we were hot shit if we could get the leak down to 3 percent. Now youre nothing more than a back yard hack at 3.

Slathering them up is old school, but unless your using pale oil (and sparingly at that) your throwing away a ring seal you thought impossible...

Like I've said before in here, anyone that thinks they can transfer how racers set their bikes up to how the average rider should is a fool. Settting a bike up for professional level racing has only one criteria: make the bike as fast as possible for racing. As it relates to piston rings and other combustion chamber tolerances, the race engine builder will always go towards as tight as can be achieved while not inhibiting operation. What does the racer care about longevity? All he wants to do is win the next race. Since the engine will likely be torn down after 1 or 2 races, the engine builder has little concern for what works long term, only with what wins races. Cost is usually not a big factor to a pro race team, either. Not as important as winning.

Those of us who actually expect to go many miles or numerous races between teardowns would be foolish to put too much stock in how a race bike is prepped. It just isn't relative to how we ride our bikes. Processes, products and techniques aimed at professional racing are, for the most part, inappropriate for the average rider who wants reliability and long life from their motorcycles in addition to going fast. What works for the pro racer is not always the right choice for everyone else.

[Shawn_Mc]

Like I've said before in here, anyone that thinks they can transfer how racers set their bikes up to how the average rider should is a fool. Settting a bike up for professional level racing has only one criteria: make the bike as fast as possible for racing. As it relates to piston rings and other combustion chamber tolerances, the race engine builder will always go towards as tight as can be achieved while not inhibiting operation. What does the racer care about longevity? All he wants to do is win the next race. Since the engine will likely be torn down after 1 or 2 races, the engine builder has little concern for what works long term, only with what wins races. Cost is usually not a big factor to a pro race team, either. Not as important as winning.

Those of us who actually expect to go many miles or numerous races between teardowns would be foolish to put too much stock in how a race bike is prepped. It just isn't relative to how we ride our bikes. Processes, products and techniques aimed at professional racing are, for the most part, inappropriate for the average rider who wants reliability and long life from their motorcycles in addition to going fast. What works for the pro racer is not always the right choice for everyone else.

I'd expect more from someone that claims to be professional.

I think anyone a fool for disregarding any technique simply because they disagree with it's application. That neither validates or discredits the technique in any manner. It simply bristles with arrogance and ignorance.

I never cast aspersions. Some however sit in what they believe is an ivory tower. Guess what jack? They are nothing more than ground floor grunts just like everybody else and Id suggest they take thier noses out of the air and start paying attention.

The ugliest human trait is arrogance. And some wear it like a badge of honor.

[ripntear]

RADRick,

You have been warned. How dare you call someone a fool (laughing while typing). The free speech censor police are being dispatched to your house to wash your mouth out with soap and teach you some manners. Bed tonight without supper and no thoughts of Top End rebuilds for a minimum of 50years.

That'll teach you!

[ripntear]

I'm honin my cylinder, oilin my piston and rings and hopefully I'll remember where all the bolts go ?

I'll let you know if my bikes still runnin next week. Well hopefully I can get it started

You did exactly what you should have done:

1. Asked around.

2. Heard different opinions from different sources.

3. Weighed the answers.

4. Made an informed decision.

[Wayward Son]

and like i promised,this thread has run its course.