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My dealer told me not me not to worry about the break in period to much. He also told me to stretch the gears a little. He said the car will perform better in the long run. I still am keeping it under 4500 rpm's though. Should I follow his advice, or keep doing what I am doing? I have a manual 330i if it makes a difference. Thanks for your help.
 

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The Original Dr. Phil
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Might get better results if you asked for

Jon SHAFER :dunno:

FWIW stick to the break in guide lines. Better to be safe then sorry and the concensus here is that they are good rules to follow.
 

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Hummmmm, let's seeeeee, your dealer might want you to break the engine in wrong so you have to get another in a few years???

I think general consenious here is to break in with what the manual says...keep it to 4500 or less for 1200 miles, then gradually work your way up.

Proper break in also usually results in better oil consumption for the life of the motor.


(flame suit on)
 

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RE:

I concur with the others. It is best to stick within the guidelines laid out by the manufacturer... While I don't think that any long-term damage will occur as a result of an over-rev here or there, it's only 1,200 miles, so what the heck?

:dunno:

Keep in mind too: your ECU (and, by extension, BMWNA) is watching your every move...
:yikes:
 

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Re: RE:

Jon Shafer said:
Keep in mind too: your ECU (and, by extension, BMWNA) is watching your every move... :yikes:
Jon, you are scaring me. How do I remove this ECU to avoid the wrath of the BMWNA? God, I thought Hoover was dead.

Patrick :D
 

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This is related to motorcycles, but the concept is the same.

"...As for break-in, proper heat cycling of the engine is really more important than rev range. Many parts in a new engine have internal stresses from manufacturing processes, which are slowly released by heat. If you took a piston out of your 13-year-old Ninja and one from your absolutely brand-spanking-new GSX-R and put both in an oven at 500 degrees Fahrenheit for half an hour, you'd be surprised at the outcome. The 13-year-old scarred and worn-out piston will look like it did when you put it in. The new piston will be warped and completely destroyed. The reason is that heat unlocks the internal stresses and allows the molecules of the metal to rearrange. The same process happens inside the engine during break-in, but the cylinder walls confine the piston. Many heat cycles later, the piston has relaxed and taken on the desired shape inside the cylinder.

The bottom line - gentle break-in is important for all friction surfaces in the engine. Piston rings, crank and cam bearings also need time to bed in and heat cycling allows clearance tolerances to settle. Also during this process a small amount of metal is collected in the oil from components coming to agreement on what size they are going to be at operation temperature, which is why it's important to change the oil and filter within the first 600-1000 miles on the engine.

Other items not commonly thought of during break-in but very important for safety are suspension bushing, brakes and tires. The handling characteristics of a new motorcycle will change as these components break in. Proper suspension sag cannot be set until the bushings and shock loosen up with wear, and if you have the will power it's wise to wait until after the first scheduled service before doing any aggressive riding on a new motorcycle...
Here is the site I got this from:
http://www.t5net.com/common/faq/Engine/enginebreakin.html
 

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I love my beautiful wife.
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Great post :thumbup:

That is the best explanation I've read on the importance of a proper break-in.
 

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Parking Spot Maven
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Great info Chip! :thumbup:

Why can't the manufacturer just tell us that stuff when we ask? :dunno:

--SONET
 

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Here is the site I was originally looking for:
http://mototuneusa.com/break_in_secrets.htm

I was talking to a guy who runs several AMA Superbike/Formula Extreme and SuperSport championship teams he has says that when he gets a new crated bike for the race team he heat cycles the engine to break it in.

I don't remember the specifics, but basically he put it on the dyno under load and just hammered the throttle, it would get hot and he would stop and let it cool. Then he did this a couple more times. The jist was to heat cycle the engine. Let the part expand and contract (heat and cool) several times.

The above website includes some great detail including pics of pistons pulled from engine that were babied during break in and those that were "heat cycled"
 

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Parking Spot Maven
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Those articles contradict eachother. :dunno:

The second one seems to make more sense though. Oh well, too late now - I'm at about 700 miles now. I'm catching up to you quick Jon! ;)

--SONET
 

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SONET said:
Those articles contradict eachother. :dunno:

The second one seems to make more sense though. Oh well, too late now - I'm at about 700 miles now. I'm catching up to you quick Jon! ;)

--SONET
Seems to me the common theme in both is heat cycles vs engine RPMs. Although one talks about pistons and the other rings they both seem to say you need to let the engine heat up and cool down so everything expands and contracts.

I dunno. I have always followed the manufacturers suggestions and never had a problem. It's like the chicken or the egg!:banghead:
 
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