Break in time before switching to synthetic.


15 replies to this topic
  • v8rman

Posted October 27, 2013 - 10:06 AM

#1

My yz 450 motor probably has less 12 hrs on it. I think it would be ok to switch to synthetic after 5 hrs.

What's your story?


Edited by v8rman, October 27, 2013 - 10:40 AM.


  • grayracer513

Posted October 27, 2013 - 12:01 PM

#2

There isn't any reason why you couldn't have broken it in on synthetic in the first place.

Please don't tell me that you still have the original oil fill in it at 12 hours.

  • v8rman

Posted October 27, 2013 - 12:10 PM

#3

No not original oil.
Synthetic oil is a bad idea when breaking I'm a 4 cycle motor. I thought most people were aware of this. The synthetic oil works a little too good and doesn't allow the rings to seat

  • grayracer513

Posted October 27, 2013 - 02:36 PM

#4

Most people are aware of an enduring myth.  There is absolutely nothing wrong with using synthetic oil during break-in.  Several of the most expensive high performance automobile engines made are shipped with it from the day one start-up, and many will void their warranty unless you can prove you never used anything else.

 

The only flaw in using a synthetic for break-in is that it's expensive to throw it away when you change the oil after the first hour of running. Otherwise, it's a complete crock, pure and simple.



  • Spud786

Posted October 27, 2013 - 02:51 PM

#5

You mean like mobil1, rotella t6? those are okay I think they are talking about real synthetics, Ive seen some of the group 5's right on the bottle in the past, say avoid use during breakin. some have noted not to use in the first 1500 miles with a new motor.

Personally , I think 300 miles of street with strong bursts of accel and decel, and a final top end run at 299 miles, equals broke in good enough to switch.

  • grayracer513

Posted October 27, 2013 - 03:42 PM

#6

Mobil1 is a real synthetic.  At least most of the line is, including the only two that should be used in a YZF, V-Twin and Racing 4T.  They're straight poly-alpha olefins.  Any oil that's so full of friction modifiers that it would be labeled as unsuitable for break in would probably fail to meet the T90 spec of JASO MA, which means it won't work with a wet clutch anyway. 



  • v8rman

Posted October 27, 2013 - 03:45 PM

#7

Personally I think this is a valid concern. I know a fellow club member had some experience with this issue, so I do not agree with running synthetics until the motor is broken in.

I don't mind hearing other opinions. Actually the reason I thought about this subject is because my son just bought a Harley and they didn't recommend using synthetic oil until 1000 miles. Don't know what the big 5 recommend.

  • grayracer513

Posted October 27, 2013 - 08:30 PM

#8

OK, one of you who believes this please explain how it is that synthetic oils interfere with breaking in a new engine.



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  • v8rman

Posted October 28, 2013 - 06:50 AM

#9

Just makes sense to me. The load factor is a lot higher with synthetics. Less friction etc. With a regular oil the rings would be exposed to more wear, therefore allowing the rings to conform to the cyl. shape.

I imagine the engine manufactures you mentioned are rather high performance motors and would have tighter tolerances. Perhaps they have already been "run in" at the factory.

  • v8rman

Posted October 28, 2013 - 07:17 AM

#10

Back in the day as an auto mechanic we used a straight sae 30 with no additives to break in new motors.

  • grayracer513

Posted October 28, 2013 - 09:08 AM

#11

I imagine the engine manufactures you mentioned are rather high performance motors and would have tighter tolerances. Perhaps they have already been "run in" at the factory.

 

Imagining and knowing for a fact are two different things.  One of the "high performance" cars being shipped with synthetics oils in them (since 2011) is the entire Honda car line.  That's primarily because you can't really make a 0w-20 motor oil out of pure petroleum base stock.  The Cadillac Northstar family of V8's, their high performance V6, and the Corvette and Camaro HP engines are sometimes "dead spun" on a machine that turns the crank without firing the engine, but this is done WITH the same original factory fill of Mobil1 full synthetic.  In today's world, where there is the expectation that engine in a new car will last AT LEAST 200,000 miles.  That can't be accomplished without holding tolerances during manufacturing that are equal or better than those sought after by race engine builders 30 years ago.

 

Just makes sense to me. The load factor is a lot higher with synthetics. Less friction etc. With a regular oil the rings would be exposed to more wear, therefore allowing the rings to conform to the cyl. shape.

 

This belief is based on three fundamentally false premises. 

 

The first is that there is some major difference in the lubricity of synthetic oils.  There isn't.  Oil out of the ground is loaded with stuff that has to be removed and separated from from it in order to turn it into motor oil.  Group IV and V oils (PAO's and esters) are built from scratch in a lab, so they are by their very nature completely free of any contaminants that weren't deliberately included in them.  Even the Group III oils that are so highly refined as to be legally allowed to call themselves "synthetic" are not as chemically pure as the group IV/V oils.  But that doesn't make them slipperier, nor does it make them lube any better.  That's all done with the additive package, same as with Groups I, II, and III.  What true synthetics are natively capable of is improved thermal endurance and tolerance of contaminant accumulation compared with conventional oils.

 

Remember too, that your bike has a wet clutch.  JASO MA and MA2 requirements include a lower limit on the coefficient of friction allowed in MA/MA2 oils, which are the ones approved for use in wet clutch systems.  The oils that ship in the new Honda car line are heavily friction modified to be usable with a wet clutch, and yet there they are in a brand new engine.

 

Next, there is the assumption that a lot of wear needs to take place immediately in order to seat the rings, and that too slippery an oil will prevent this.  There are two parts to this misconception, the first being the question of the tolerances involved.  You may recall from earlier in the thread where I mentioned improper engine prep as the primary cause of rings failing to seat.  If the cylinder is not round and straight within the manufacturer's service limits, it will almost always fail to seat the rings to a good, efficient seal.  Using such a cylinder is asking for trouble, and the oil won't affect the matter.  Current manufacturing methodology produces cylinders that are normally within .0003" of perfectly straight and round, and rings to match.  Which brings me to the second flaw in this belief; there's no oil on the compression rings in the first place.  Any oil that was present above the oil ring will burn away in the first 2 minutes of operation, and if the engine was prepped right, the oil rings will be 99% completely effective upon installation. 

 

Because the 3 piece double rail/expander oil rings are so efficient, compression rings are lubed by the fuel and very, very little else.  If your YZ450 averages 6500 RPM, it would need no more than .005 of an ounce (.15 ml ), a tiny fraction of a drop, in the combustion chamber each time it fires to burn through a pint of oil in an hour.  Most of them don't burn any measurable amount of oil, so you can see from that just how dry the environment that the compression rings live in is.  The oil just simply has nothing to do with it because it isn't there.

 

The third major problem with the logic is connected to the first one about lubricity.  If you offer the premise that you need to encourage wear, and that you can't use certain oils because they lube too well, then the logical result of following that thought is that you want the lubrication in your new engine to fail.  This is complete nonsense, particularly in the first 30 minutes of the life of a brand new engine.  The parts that really hold everything together need the best lubrication they can get during that time. 

 

Normal wear in an engine is NEVER the result of metal on metal contact.  Never.  The smooth, nicely polished appearance of a good healthy, high hour engine part is all done by the oil itself.

 

And the truth is that even a plain old Group I straight grade 30w petroleum oil isn't going to fail to lube anything in the first 30 minutes of the engine's life, either, so it doesn't matter to the rings one way or other.  There's no problem with using a good conventional oil for break in if you insist, the point is simply that there is absolutely no reason not to use a synthetic oil that would otherwise be appropriate for the bike just because you're breaking it in.



  • gscx

Posted October 28, 2013 - 09:28 AM

#12

Pwnt.

  • v8rman

Posted October 28, 2013 - 10:08 AM

#13

So in essence motors shipped with synthetic oil in them are high performance motors. The break in oil for a yz 450 doesnt really matter because it was not designed to run strictly synthetic oil. So the only part of my argument you have a problem with is that I think synthetic oils should not be used because of their superior lubricity.

So knowing what we know now, why would a manufacturer not recommend using synthetic to break in a motor?

  • ka24s14am

Posted October 28, 2013 - 10:30 AM

#14

I break in my bikes with fully synthetic, never had any issues. I always break them in on a MX track and do heat and cool cycles.

  • grayracer513

Posted October 28, 2013 - 02:06 PM

#15

So in essence motors shipped with synthetic oil in them are high performance motors.

 

 

Like the Honda Accord Sedan and Pilot. Not.

 

 

... the only part of my argument you have a problem with is that I think synthetic oils should not be used because of their superior lubricity.
 

 

No, the part I disagree with is that there is any reason at all to avoid using synthetic oil during break in.  Manufacturers make a lot of odd recommendations, some that make sense in a modern world, and some that are made because, well, we always have.  There's probably somebody from risk management involved.

 

 

 I always... do heat and cool cycles.

 

That's another one.  Harmless to do that, but there's no benefit to it, either.  The only thing I pay attention to with a new engine regarding heat is to make sure that it is actually warmed up before loading it hard. 



  • v8rman

Posted October 28, 2013 - 02:33 PM

#16

[quote name="grayracer513" post="11137739" timestamp="1382997988"



No, the part I disagree with is that there is any reason at all to avoid using synthetic oil during break in. Manufacturers make a lot of odd recommendations, some that make sense in a modern world, and some that are made because, well, we always have. There's probably somebody from risk management involved.



That's another one. Harmless to do that, but there's no benefit to it

While I respect your obvious knowledge of modern 4 cycle motors, I still think the safe path to take is to use my antiquated way of thinking. You have said there is no benefit in not using synthetic oil for break in, but I see no compelling argument for using it unless a manufaturer recommends it.







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