[Kevin_The_Clean1]

Originally Posted by kyrix1st

I believe BMW still uses the conventional "break-in engine oil" with special additives for bedding in the piston rings. So I would stick with the 1200-mile break-in under normal circumstances.

Exactly. This is the very same point that some people seem to keep missing & glancing past. We still have no idea what weight of the factory fill before the RIS is completed truly is. When the mind doesn't want to acknowledge thing it selectively chooses a different path. Sure it would cause no harm, but in the long run I don't think it's going to make a stronger engine. In fact, it might be a touch weaker.

[aerobod]

With the new pistons and camshafts I’m installing in my Caterham, the manufacturers quote the majority of ring and cam lobe break-in is accomplished in the first 20 minutes of running between 2000 and 3000RPM or 30km of moderate road use in those rev ranges. They then allow full-load dynomometer runs after that. This is with modern thin (1mm) low spring rate rings with a 45 degree cylinder wall cross-hatch pattern.

[RockCrusher]

Originally Posted by kyrix1st

I believe BMW still uses the conventional "break-in engine oil" with special additives for bedding in the piston rings. So I would stick with the 1200-mile break-in under normal circumstances.

That has to be some magical oil to allow just the right amount of wear yet avoiding excessive wear.

My experience is the rings break in (seat) within a minute or less time after firing up a rebuilt engine. Since the cylinder wall finish was done to what the factory called for and the rings were factory supplied rings I have to believe this ring seating time was similar to what a new fresh off the factory assembly line engine would experience.

The rebuilt engine was filled with the oil the factory recommended and was nothing special.

The rings seat because the cylinder bore finish is conducive to causing wear to the rings so they quickly make full contact with the cylinder.

At the same time the cylinder walls wear too. The cylinders do not wear smooth though. One can still see the crosshatch pattern in the cylinder wall. This provides depressions which retain oil and help prevent further metal to metal contact.

For non iron cylinder material the process is a bit different. But the end result is rings still seat and thus conform to the cylinder.

I'm hesitant about passing this on but I was told yesterday for the M engines they are run on a dyno before being installed in a vehicle.

I don't know how long.

Another car brand it was claimed its highest performance engines were run for 42 minutes. Not allowing any additional time to get the engine into the dyno and hooked up and then after the run disconnect the engine and remove it from the dyno and then change the oil/filter, for say a run of 10,000 engines this dyno run time represents 420,000 minutes, or 7000 hours, or 291 days.

Anyhow, I was told at the end of the time on the dyno the oil/filter is changed.

I have no details on if this is special oil or just plain old BMW oil. I would have to believe that it is plain old BMW oil.

If (big if) the above is the case then the M engines at least come with some run time. Not broken in (completely) but at least with the rings seated and I'm sure with some confidence the engine is free of issues and makes the advertised power. While the rings seat running on the dyno the engine is not broken in. That takes the engine in a vehicle and running and powering a vehicle over a span of time during which time it experiences a variety of loads which allow the break in process to progress to the point the engine is considered out of break in and ready for whatever...

And if (again big if) the above is the case then that can explain why there is nothing in the owners manual regarding a *premature* oil/filter service. There is no restriction necessary because there is no special oil/additive package being prematurely removed.

To be sure there are restrictions even after the engine has done its time on the dyno and is now in a vehicle. Mainly RPMs and vehicle speed restrictions. This is in recognition that a new engine (and drive train) has a higher level of friction and friction is heat. The limit on RPMs is to avoid a too high an engine speed that results in excessive heat causing a break down in oil and damaging say the cylinders/rings. But it can also compromise a cam lobe and lifter.

[DutchBoysRacing]

So my cars been stuck at the VPC for some reason. Its been over a week since it got to Oxnard VPC (12/7/2023). I know other forum members got their cars on the 10th and 11th from the same vessel + vpc.

If I go over my miles (1200) for break in, does it void my warranty? For example, if I go do my track day after hitting 1200 miles but don't do the service.

[JABCAT]

Originally Posted by DutchBoysRacing

So my cars been stuck at the VPC for some reason. Its been over a week since it got to Oxnard VPC (12/7/2023). I know other forum members got their cars on the 10th and 11th from the same vessel + vpc.

If I go over my miles (1200) for break in, does it void my warranty? For example, if I go do my track day after hitting 1200 miles but don't do the service.

I wouldn't do a track day before having the break-in service completed. Everything I've read, and talking to the SA, says there's a very small window BMW accepts past 1,200 miles. I've seen between 50 & 150 miles.

[FrankWhite!]

Originally Posted by JABCAT

I wouldn't do a track day before having the break-in service completed. Everything I've read, and talking to the SA, says there's a very small window BMW accepts past 1,200 miles. I've seen between 50 & 150 miles.

I’ll call BS. I had my service at 1500 miles and they didn’t say a word.

[RockCrusher]

Originally Posted by DutchBoysRacing

So my cars been stuck at the VPC for some reason. Its been over a week since it got to Oxnard VPC (12/7/2023). I know other forum members got their cars on the 10th and 11th from the same vessel + vpc.

If I go over my miles (1200) for break in, does it void my warranty? For example, if I go do my track day after hitting 1200 miles but don't do the service.

I agree with JABCAT. Would not track the car before having the break in service done.

Don't have any knowledge of if delaying the break in service has any effect on the warranty. There is probably some upper threshold.

Regardless I would not risk the engine in trying to delay the break in service very much beyond the 1200 miles.