Britbike forum Forums British motorcycles in general British motorcycles in general Break in oil

I recently had the displeasure of having to disassemble a newly built motor. It was started and run for about 5 miles on cheap 30w non detergent oil. The new cams and lifters were scuffed in that short amount of time. The case for using a high zinc break in oil got stronger for me.....

Mike,
Did the builder use assembly lube?

Ed from NJ

I am the builder. Yes, I used Harley Davidson assembly lube. I find it to be quite thick and sticky, moreso than the red permatex lube.
This is a race motor that suffered a top end failure. Valve spring pressure is set fairly high so that could have had something to do with the scuffing.
The research I've done has indicated that Lucas break in oil has significantly more zinc than others.

I wrote earlier that:
I had mis-remembered that the approximately 500 pages in the 2" binder were API and SPIE, but it turns out most also are ASTM publications on engine oils, that aren't bound in booklet form.

Assembly lube dissolves in oil so its function is to protect the wear surfaces of a new engine in the crucial initial seconds until the oil pump manages to get oil to the remote locations. Once the oil reaches it, it's washed away so no longer offers any protection. Even if the assembly lube itself has a very high Zn content, the total quantity of it is so small that, once its dissolved in 4 qts. of oil, the overall Zn content of the oil will be raised insignificantly.

Lucas break-in oil, which is what I also use, has a Zn content of 3635 ppm. As already mentioned, after break-in, I then switch to Valvoline Racing Oil boosted to at least 2000 ppm with Lucas Zn additive. For what it's worth, I'm not necessarily recommending Valvoline over any other brand of oil, but I am recommending 2000+ ppm based on my research. Anyone who feels that oil with a lower Zn content is fine is welcome to ignore my recommendation.

I thought that zddp is only a last resort for when the oil film has broken down due to thrashing. In my 650 handbook it says that when using full performance you should close the throttle occasionally to suck some oil in to the cylinders. I never ride like this although they were expecting me to.
Dave

Agree that assembly lube is very temporary.
Since I've started racing I've had to maybe not ignore what I've learned building street motors, but understand that it is only a starting point for making a reliable race powerplant. If my school of hard knocks education can help someone else, that's good.
And like MM, feel free to think I'm full of scheise.

I know of a race engine builder that will run the engine at 2000 rpm with lighter valve springs for 20 minutes to break in the cam, and then fit the complete racing spring package. He says that is the best way to get his preferred cam and tappet combinations to survive. I don't know if that makes sense in your situation but I suppose it's worth knowing about the option.

Because of the microscopic asperities on the as-machined tappet and camshaft surfaces, the initial pressure on the oil will be much greater than it will be once the asperities are worn away during the bedding-in process.



Since Pressure=Force/Area, initially the oil film will be supporting just the peaks of the asperities so the Area will be small, and hence the local Pressure on the oil film will be high. If the oil isn't up to the task, and too much contact takes place, the frictional heating will be enough to cause localized welding, transferring metal between the two components that in turn will cause scoring or scuffing. However, if the break-in oil is up to the task, only a fraction of the asperities will make contact at any one time, so the frictional heating will be small, and the surfaces will bed into each other without problem.

Even after the cam and tappet are bedded in, there still is high pressure on the oil film between them. And it's not just the force of the valve springs, it's also the additional force due to the inertia of getting the mass of the tappet, pushrod, lifter, and valve into motion. Our Britbike engines operate at fairly high rpm, and inertial forces increase with rpm. That's the reason for a high Zn content (~2000 ppm) even after the engine is broken in.

I think considering the complete oil additive package before choosing an oil is worthy of some thought.

I would be looking for an oil additive package that has some of the following anti-wear additives:-
- a high level of ZDDP somewhere around 1800-2000 ppm. Note that the ZDDP is a polar molecule attracted to metal surfaces but only activated under heat and load, when the ZDDP is activated it forms a phosphate glass film, protecting the underlying metal. I don't know how much heat and load it needs to activate, so that's something to research.
- Boron offers much greater protection than even Zinc by increasing the load-carrying capacity of the oil by as much as 8 times in a 4-ball load test.

Inside the engine, other additives like detergents, dispersants, and viscosity index improvers compete against the Zinc by trying to disperse it or compete with it for surface space, possibly with negative consequences.

So there is good reason for having a high level of ZDDP level and also some Boron to protect the engine.

If the ZDDP hasn't been activated by heat and pressure and turned into a phosphate glass film, there is a danger that the ZDDP could be washed away by the detergents, dispersants and VI improvers.

Just my tuppence worth of course.

This is where I leave this oil thread, since such a discussion almost certainly will be mostly opinions, not facts. I'm happy to trust that any major name-brand oil (e.g. Valvoline, Castrol, Havoline, etc.) will have the additives, other than Zn, that will keep my bikes happy, and not spend the time trying to determine what each brand contains, and then try to compare which individual additives in a given brand might be better or worse than those in another.

One of the really big improvements in oils over the eons have been the additive packages that reduce rust and corrosion
- particularly from the acidic blow-by products that occur in the 1st few minutes from a cold startup.
If you get your used oil analyzed by one of these oil analysis co's, its often one of the first things they report that has been depleted.

And as any taxi or truck driver will tell you, if it never cools down it will never wear out..........................................

I agree and I was basing my thoughts on the additive package in the MOTUL 20w50 classic oil I mentioned earlier which has a high ZDDP level of over 1800 and also Boron as an EP anti-wear additive.

Of course, without rigorous scientific tests, it's impossible to determine how these oils perform in the real world, so I guess its down to the individual to choose which is best for their bike.

Pretty much standard procedure for most serious auto engine builders to run at 2000 rpm for twenty minutes often with light springs to break-in cam and lifters. Fine for a water cooled engine not so much for our air cooled ones. Even with a large fan on I would still be afraid of excess heat build up after even a couple of minutes. If I can I like to do first starts when the weather is cooler. Also, start it up and never let it sit and idle keep the rpm above 2000 for a few minutes. Then go on a ride always keeping revs above 2000 even when you are caught at a light for the first 100 miles or so.. Need to ensure that splash lubrication is going on. Also, try to minimize time spent trying to dial in an idle. Got plenty of time to do that after the engine is broken in.

Are we actually talking about running in just the rings and bores? Is break in oil ok for the rest of the engine or do you change to a normal mineral 20w50 after the rings have seated?

Dave

If you have installed new cam and lifters proper break-in of those is critical. As mentioned auto engine builders say 20 minutes to break in a new cam. Rings generally do most of their breaking in during the initial start but will continue to bed in say for the first 500 miles. The engine might smoke a bit out the pipes on first start but should stop shortly after indicating initial ring break in occurred. If you used a 20/50 dedicated break in oil, I would use it for the first 500 miles and then change to your normal preferred oil along with a new filter.

...Hi; may be a dumb question but how about the clutch slip with a SAE30? Is for cars not bikes

Content type zinc phos
Champion Racing Oil Synthetic Blend 1,600 ppm 2,000 ppm
Synthetic 1,600 ppm 2,000 ppm
Champion Power Shield Engine Break-In Oil Conventional 2,700 ppm 2,400 ppm
COMP Cams Engine Break-In Oil Conventional 2,600 ppm 2,500 ppm
Lucas Racing SAE Oil Synthetic 3,130 ppm Not Disclosed
Conventional 3,130 ppm Not Disclosed
Lucas Hot Rod & Classic Oil Conventional 2,100 ppm 1,900 ppm
Lucas Magnum Diesel Oil Synthetic Blend 1,400 ppm Not Disclosed
Lucas Engine Break-In Oil Not Disclosed 3,630 ppm Not Disclosed
Mobil 1 Extended Performance 15,000 mile Synthetic 890 ppm 815 ppm
Mobil 1 Racing Oil Synthetic 1,850 ppm 1,750 ppm
PennGrade 1 Synthetic Blend 1,500 ppm 1,340 ppm
Red Line SAE Oil Synthetic 1,200 ppm 1,200 ppm
Red Line 40WT Synthetic 2,400 ppm 2,200 ppm
Red Line 50WT Synthetic 2,350 ppm 2,050 ppm
Red Line 60WT Synthetic 2,250 ppm 2,000 ppm
Royal Purple Duralec Utlra Synthetic 1,050 ppm 960 ppm
Royal Purple HPS Synthetic 1,775 ppm 1,350 ppm
Royal Purple Break-In Oil Conventional 1,150 ppm 1,030 ppm
Valvoline VR1 Racing Oil Conventional 1,300 ppm 1,200 ppm
Castrol GTX Conventional 610 ppm 750 ppm
Mobil 1 Advanced Fuel Economy Synthetic 740 ppm 675 ppm
Motorcraft Synthetic 600 ppm 740 ppm
O’Reilly’s Conventional 850 ppm 800 ppm
Pennzoil Conventional 830 ppm 840 ppm
Shell Rotella T Diesel Oil Conventional 1,450 ppm 1,050 ppm
Valvoline SynPower Synthetic 950 ppm 750 ppm

If you like reading about oil comparisons.

https://www.accessnorton.com/Oil-Tests/NortonOil.php

NickL, why are there two ppm figures for each item on the list?

first one is ZDDP second one is phosphorus.


It's all BS anyway, thousands of these old heaps were and are run on oils which
have much lower zddp and phos levels than these. They may suffer by only
lasting 25 years rather than 50, so what?
Up until a few years ago no-one used assembly lube either, i've stripped motors
that have run on oil with more dirt than zddp and they've cleaned up ok.
I don't really understand the obsession with using the very best and most modern,
most accurate, most expensive parts and methods on these old crates. They are
what they are, in my books anyway. Plus the fact that 99% of users never ride the
things on the red-line anyway, in fact most only do a few miles of plodding about.

Amen !!


Aye !!
And those that do risk mayhem and destruction !!!

In the mid 1950s, the SAE (Society of Automotive Engineers) selected a variety of new cars off the showroom floors,
ran them in on the road as recommended - and then ran them flat chat on a dyno to see what would happen.**
They (Chevs Fords Chryslers)(2 each ?) lasted an average of 7 minutes.

Conclusion(s) ?
The oiling systems weren't capable of sustainably supplying oil under pressure under those conditions.
And the cooling systems didn't adequately cool the important bits enough.
And the rods and cranks and pistons etc weren't high enough strength items to survive hard use.

Its been commented that Brit Bikes were about the same in that era. (but weren't tested, as such ?)
There were no motorways in the UK until the mid to late 1950s in the UK,
and bikes simply weren't developed for that sort of treatment.
Unless you roam into Manxs and 7Rs and KTTs and Goldies.
Or bikes that ran at Brooklands prewar (often on alcohol).

Once motorways appeared, engine development ratcheted up a number of notches.
And MIRA had an oval where they could safely explore high speed running.


We diverge from oils, a tad.
But Castrol R had no zinc, no P, no detergent, emulsifiers, anti-foaming agents, anti-corrosives.
And was the oil of choice for engines giving max performance, for decades.
What does that say ?

**The SAE tests used to be open and accessible online, but then they implemented user pays ..

whats a red line?

The red-line is the thing obscured by the red-mist...............

I just want the damned thing to not smoke. This is my third attempt at a successful break-in on this TR5T. I think I know what I did wrong (wrong crush washers under the pushrod tubes), but I'm crossing all the "T"s and dotting the "I"s this time. I will use Penn Grade SAE 30 break-in oil, and then switch to some brand of 20W50 after break-in, probably Castrol.