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I was browsing a local bike forum, getting as much information as I possibly can, and I came across this....

http://www.mototuneusa.com/break_in_secrets.htm

Anyone have any opinions on this?

I don't know enough about this kind of thing to make an educated opinion in either direction.

Professor? Vikash? Anyone? Ideas? Thoughts? Concerns?

I know a local at MachVMotorsports (sure you guys have heard of them), has an SRT-4. He redlined it right off the lot, and has been going STRONG since he got it.

I've read that before over at NABISCO. Seems to make sense but I have no idea if it's really true or not.

First, most vehicles I've seen have over or close to 20 miles even if they're brand new.

Second, a lot of companies break their engines in at least partially at the factory.

Third, while this might apply to 13k rpm bikes, I don't think it makes as much difference in a car as far as sealing, though I would tend to agree and lean towards a more aggressive break in than too passive. In no case should you drive at a constant speed to get the mileage over with. I wouldn't call it BS, but I guess I'd fall somewhere between his method and the book method.

Steve

I've been wary of the break-in on modern engines for a long time. I think it's more of a ritual than anything nowadays.

Well, Steve, I'm looking at 12,000 RPM's that I have to work with on the bike, and 0.05 miles on the clock (no sportbike test rides, and they are crated and shipped, no need to drive them to get them anywhere).

So I have those precious first 20 miles to work with.

Factory spec says under 4,000 RPM for the first 500 miles, and from 500 to 1000 miles, I have to stay under 6,000 RPM. But I have 12,000 RPM's to work with!!!! AHHH!!!!

So I have been thinking that I will simply ride however I feel comfortable. I'm not gonna hit the redline for the first 20 miles probably, but I'll probably go to 6k or so.

Why would car makers suggest a method of break-in that can actually harm engine performance?

I think the theory is logical but I don't know how practicle it is. In your case where you'll have those 20 miles to work with, I don't know. I'd say that most break-ins now-a-days are a little on the easy side. But I'm no engine expert and have never actually owned a car with less than 170k on it.

I've yet to own a car that has less than 90k on the clock. This will be the first vehicle I have seen roll over 1-mile.

Me? I dunno. I just buy used cars.

I was tuaght(sp?) to drive it how it's going to be driven by a good backyard mechanic friend of mine, and have witnessed his "break-ins" and his engines have lasted a long time. This is on reconditioned old original parts (block, ect) in typical hot rod fashion. This is how I broke-in my 390 in my 1966 Ford F-100. I've only put on around 15,000 miles in the last 5 years, I'm in process of transferring it over to another, long on-going project.

I can tell you that piston aircraft engines are run hard for the first 50 hours or so. Granted, they don't see over about 2700 rpm at WOT because of the propeller, but a new / overhauled engine is always placarded against extended low throttle operation until the first oil change usually. They're also run on mineral oil for that time frame.

I'm going to have to disagree.

The worst thing you can do to an engine in the break-in period is drive it at constant high speeds. That will basically break-in only one side of the rings, the side that is forced against the cylinder under load. This is 10 times worse than running the engine hard at a variety of different speeds.

I would like to add something I read in the Car and Driver four-seasons test of their Evo. They were explicitly informed that if they are easy on the engine for the first 1000 miles, the engine will break-in with more power, and will not burn oil later in its life. Following those instructions, they babied it for the first 1k and then commenced the abuse . They said they never had to add any oil ever in the 40,000 mile test, and they talked to other owners who beat them senseless right off the lot and now had to add a quart of oil before changes.

When I finally buy a new car, before I even take it home, this is what I will do to it: I will drive to a deserted road and accelerate from 30mph to 50mph, then decelerate under engine braking back to 30mph and repeat that process about 10 times. Then for the next 1000 miles I will try to balance acceleration and deceleration under engine braking as best I can, and then after 1000 miles, I will change the oil.

What they say on the site i think has some merit. The worst thing you can do is baby/lug an engine during break in.

I think it depends on the application. If you're building a race engine, then yes this method may have its advantages. But if you're driving an engine as a daily there is no reason to sway from the manufactures recommendations.

ok, moving on past the break-in stuff, he has an article on head porting- and according to him, our heads ARE BETTER than the wrx ones.

You should read this:
http://mototuneusa.com/think_fast_intake_porting.htm

I'm not sure that information is as relevent for your turbo car. There is no valve overlap and the volumetric effeciency doesn't compare to that of a modern sportbike. Additionally, the sport bike is tuned to reach peak power very close to its redline, not the case with the subies.

I'd say that like everything else, there's too big, but there's still too small, his graphs just dont show that.

Phil - sounds similar to the break ins for 2-stroke outboards. I'd follow mfg recommendations, but I wouldn't just hold 4k or whatever for several hundred miles. I think it would be better to run it in in traffic so you are always accelerating or decelerating up to the rpm.

Steve

Hmmm, I've been asking this question all over.

One reply I got was this:

"I have heard this before many times. My dad who was a motorcycle mechanic and worked for kawasaki for many years told me the same things about running an engine hard in the beginning and changing the oil right away."

Hmmm, I think I'll just drive it normally and engine brake a lot.

Go with what he says, engines have different rings, piston design, or cylinder materials, requirements, and capabilities. While they may be similar in operation, I don't think break in should be the same for everything. That's a non-SAE opinion.

Steve

I'm with Steve on this. . . .

for instance, just think of all the different kinds of engine blocks. Some iron, some aluminum, some closed-deck, some open. . . They're not all going to react the same way to different kinds of heat cycling. . . that goes for heads, pistons, etc too.

There is lots of baloney in that article. Anyone who uses that much html is suspect in the first place...

the one nugget in there is the synthetic oil thing. I've heard lots of folks say to use mineral-based for the break-in, then switch to synthetic after a couple changes

Professor - What is your take on motorcycle break-in then? Should I give it a good run for the first 20 miles, or should I baby it, but change the oil before the first recomended service at 500 miles?

cars-good

motorcycles-bad

that's about as much as I know about 'em

I've always heard that lot acceptance testing on bikes included pulling a motor off the line and running it to full load/open throttle/redline a few times, then the engine gets drained and plopped into a bike. Don't know how true that is.

I did my breakin a little harder than reccomended by going full throttle to around 60% rpm fairly early, but i wouldn't go to the extent of the guy on the website. I wouldn't want to turn my bike's engine in to a science experiment.

If he is saying that the truth is opposite of popular belief for ignition advancing, fuel injection timing, cam timing etc, then I don't neccessarily want to believe anything this guy says.