Any proof 2-stroke break-in isn't as good w/synth?

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I read the below link, but what this guy says regarding against using synthetic oils isn't specifically directed at 2 stroke use, but rather 4 stroke--so is there any reason his views might apply to 2 strokes as well? (the 2 stroke piston pics show what he claims are differences from the method of break-in, not the type of oil used) From what I have seen, there are a lot of folks on both sides of the fence with this issue. Bottom line is I'm getting a new piece of 2 stroke equipment today and I'm wondering if I should break it in with say 16 or 20:1 Pennzoil air cooled (now AeroShell Oil Sport Plus 2) dino/mineral for the 1st gallon before I switch to Mobil 1 racing 2t, or just start off with the latter? Comments from others that I thought were noteworthy are in bold.

http://mototuneusa.com/break_in_secrets.htm
BreakInF3Pistons.jpg

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These Honda F3 pistons show the difference. Although these pistons came out of engines which were raced for a full season, they weren't set-up with any special clearances or other preparation. These engines were never worked on prior to being raced. They were totally stock as built by Honda. The only difference was the break in method they used...

The one on the right was broken in as per MotoMan's instructions. The one on the left was broken in exactly according to the owner's manual. The resulting leaky rings have allowed pressure to "blow by" down into the crankcase on acceleration, and oil to "suck-up" into the combustion chamber on deceleration. Needless to say, this bike was slow !!

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It is a myth that is not good to break in an engine on fully synth oil. The process just takes a bit longer (quite a while in fact). Using inferior oil for the break-in process never seemed such a good idea to me, unless you want to run the engine directly out of the box.


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The slower the running in process, the better it will be for your engine, because running in really is a damaging process, where small material particles are forced to part with the underlying metal. and hopefully, the resulting roughness is less than it was before. When the parts finally mate up correctly, there could well be more damage than needed. The more gradual the mating process, the better, and the longer you will enjoy your engine.

http://www.rcuniverse.com/forum/gas-engi...tion-print.html

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For running in the content should be high, and forget all the [censored] of different oil for the first gallons. Use the best oil you can get from the get-go. You do not want to wear an engine, you want smooth surfaces.

http://www.rcuniverse.com/forum/gas-engines/6971065-new-engine-break-print.html

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There's zero need to use a non synthetic oil during the break in. Why rush the break in? I don't know about you other folks, but like Pe and **** I prefer to have the best possible lubrication running through my engines from the first spin.


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It is important break in your engine with an oil such as lawnboy or so on. If you use a full synthetic during break in it does not allow the engine to fully break in.


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Totally not true, nothing wrong with breaking an engine in on synthetic oil and it WILL break-in completely, might take another hour or two but no problem. Do you think companies like Stihl, Echo, Husky, Poulan,and Homelite, don't know what they are doing? They include fully synthetic oil with their equipment when purchased new in the box with instructions to use fully synthetic oil from day one and forever. I've been doing it for many years, you telling ME my engine have never broken in?


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After a few thousand engines broken in with synthetic I think I can say with conviction they most certainly do break in. Those stating they do not clearly don't have all that much engine time under their belts, and are limited in the number engines they have run and the length of time they have run them.
 
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You getting a new DA-35?
wink.gif


I've been a fan of Stihl Ultra HP. For new engines I mix at 32/1 or 40/1. Tune the top for max rpm then back it off a couple of hundred. You can tell when things start working properly.
BTW, Pe Reivers was an engine genius. He unfortunately died this year and is greatly missed.
 
Originally Posted By: Taildragger
BTW, Pe Reivers was an engine genius. He unfortunately died this year and is greatly missed.

Oh wow, didn't know that. I read a lot of his posts, he seemed extremely knowledgeable. He's one of the people that recommended using synthetic from the start, and never changing brands of oil. I'm not even into RC planes, but was just greatly interested in his findings on 2 cycle oils. Some think that the whole dino vs. synthetic debate for break in originated from the automotive world:
Originally Posted By: Reg# 43897
Honestly, I cannot see it making any real-world difference. Too many people are making assumptions based upon the possibility that some four stroke engines' ring-seating was slowed by the use of a synhetic base oil. I just don't see it making any difference for a two stroke.

I can agree w/ a reduced mixture of synthetic two stroke oil on liquid cooled applications (not sure about AC apps, so I will not speculate) but that's about as far as I would go.

Originally Posted By: Cujet
I've never found that "break in" oil helps in any way.

I used to race SeaDoo's and had a small business building the Rotax race engines for local racers. At no point could I make any type of reasonable determination that wear levels changed with different break in procedures or oil ratio's.

We'd build engines, thermal cycle them a bit (start/stop, cool down check for leaks) then slowly cruise out the intracoastal into the ocean where short full throttle runs were immediately made. That was as much break in as they ever got. These things were absolutely thrashed, over-revved and run without much consideration to engine life. Yet they held up perfectly.

When they were disassembled, sometimes after as much as 250 hours of racing and practice, wear rates were never an issue.

Because a non racing engine has tighter piston to wall clearances, I'd use caution during the warm up phase, always.

I though this was a great post (talking about 4cyl though):
Originally Posted By: olddognewtrks
I'm working from memory here, from Circle Track Magazine articles, but...
The late, great Smokey Yunick found that his Trans-Am racing series engines (from Traco?)produced 20-30 more h.p. when he bolted on 'mule' heads (standard, not the racing parts) and gently broke in the shortblock for 30 hours on the test stand. These were the 305 Chevy SB engines, basing at 405 hp, and he got 430 by letting all the parts gently make friends. He had taken photos and done impressions of the rings with fast and slow break-in, and found scratches in the ring faces from fast/rough break-in.

Think about this. When you hone a cylinder, you are actually microscopically cutting threads in the cylinder wall. Cross hatching is cross threading, and the surface is microscopically torn and folded over. When the rings initially run on this torn and folded metal, it can either gently wear it away and be flushed away, or it can be torn away and be mashed into or gouge the ring face. Smooth rings seal. Rough rings can't. Secondly, think of all the VISIBLE flecks/filings/[censored] being deposited in your oil in those first few miles.

Seriously; I've seen metal flake oil from every new engine I've done an oil change on (very subtle, but take your clean pan with the oil in it and look at it in the sunlight). Do you really want to pound that abrasive [censored] into the piston skirt or bearing shells? I prefer to flush it out ridiculously early (less than 50 gentle miles) and use a new filter and oil for the next couple hundred miles, where I do start with the 'goose it and let off' cycling. And I change the oil again after a couple hundred miles.

Recent experience: Last fall I changed the oil in my new 03 Mazda Protege at about 50 miles. The otherwise new clear oil had black/gray/silver stuff in it that would actually SETTLE OUT to the botton of the catch bucket in a minute or so.
I think I'll listen to Smokey. He had patents out the wazoo and did development work for the Big Three, and ran well at Indy too.

That is in line with what the late Pe Reivers said: "Use the best oil you can get from the get-go. You do not want to wear an engine, you want smooth surfaces."
 
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Stihl thinks enough of using their full synthetic from the beginning that they double the warranty if you buy a six pack of ultra or 6 bottles of their premix at the time of purchase.

Ed
 
Originally Posted By: jhellwig
2 strokes just take a little longer to break in with syn. They still break in.

I think you are right. The thing is some people apparently carry over what they've heard regarding automotive/4 stroke applications to 2 stroke--based on info like this:

http://www.amsoil.com/shop/by-product/motor-oil/gasoline/break-in-oil-%28sae-30%29/
cylinders_500.jpg

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Quickly Seats Rings
The primary goal during engine break-in is to seat the rings against the cylinder wall. Properly seated rings increase compression, resulting in maximum horsepower; they reduce oil consumption and prevent hot combustion gases from entering the crankcase. To achieve this, however, the oil must allow the correct level of “controlled wear” to occur between the cylinder wall/ring interface while maintaining wear protection on other critical engine parts. Insufficient break-in leaves behind peaks on the cylinder wall that prevent the rings from seating. The deeper valleys, meanwhile, allow excess oil to collect and burn during combustion, increasing oil consumption. Too much wear results in cylinder glazing due to peaks “rolling over” into the valleys and preventing oil from collecting and adequately lubricating the cylinder wall.

AMSOIL Break-In Oil’s friction-modifier-free formula allows the sharp peaks on newly honed cylinder walls (fig. 1) to partially flatten. The result produces more surface area for rings to seat against, allowing formation of a dynamic seal that increases compression, horsepower and torque (fig. 2).

Notice that Amsoil doesn't manufacture a "break in oil" for 2 cycle engines? If one was warranted you'd think they'd have created such a product by now.
 
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There is also a school of thought that it isn't the oil that affects the break in as much as the way the engine is operated. The harder the engine is round the better the rings seat.

The nice thing about two strokes is that the only part of them to break in is the rings. All the other moving parts are on ball or needle bearings that don't have anything to break in so it can bee run hard from the begining.
 
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In my Husky 455 Rancher owner's manual it indicated avoid full throttle for the first 10 hours. With a chainsaw it was hard to do. It came with semi-syn oil
I break everything in like Smokey--don't rush it
 
I bought a lot of new Polaris atvs, two strokes and the Polaris dealer always said, run 8 ounces of oil in the gas tank, with the oil injection for the first two full tanks. I bought my Craftsman weed eater, 21 years ago. I ran it full throttle since it was new, I never babied and cut some serious stuff with it for long hours. I always ran it a little rich, I like all the smoke. 20:1, never leaner than 32:1. Its 21cc and still running strong. I just broke off the flex shaft, I got into some fence. I just ordered a new one. I really want to see how long that thing will run.
 
On another note, my Dad bought a McCollah, many years back. He babied it. He would just cut the weeds at a idle. rev it up every now and then. It lasted about two years. Two strokes like to run, run them hard. Why I cant believe they got replaced in Dirt Bikes, but they are coming back. I love em'
 
Originally Posted By: Panzerman
Two strokes like to run, run them hard. Why I cant believe they got replaced in Dirt Bikes, but they are coming back. I love em'


I ride a 2001 KTM 380EXC, 2 stroke. While that particular bike's 2 stroke engine is not well refined or configured, it still has wonderful advantages over many of the current crop of 4 strokes.

And, it's still on it's original set of piston and rings! Properly built cared for 2 strokes can last a long time!

As I've said before, with my 2 stroke racing engines, I simply use the oil and ratio I need from the start. And, after a few thermal cycles, the engine is ready to go.

Can you imagine a 2 stroke aircraft engine being required to remain at 50% throttle for the first 10 hours? The first flight would result in a crash. These engines are typically run a few times on the ground to check for leaks/problems and then are required to produce full power for take off and climb. AND, they hold up properly, last for years and perform very well.
 
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Originally Posted By: steve20
In my Husky 455 Rancher owner's manual it indicated avoid full throttle for the first 10 hours. With a chainsaw it was hard to do. It came with semi-syn oil
I break everything in like Smokey--don't rush it


Stihls manual says about the exact same thing, but I think it specifies no full throttle only when unloaded and not in the wood. And instead of hours it specifies 5-15 tanks of mix, which would probably put you right around the ten hour mark...

If Husky and Stihl are on the same page, its time to listen.
 
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