Car people. Hard vs soft engine break-in (Mototune method)

[Carbon]

Hard break-in vs Soft break-in

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

[Lohman446]

Noone can seem to agree on proper break in methods. Some will argue that you put it at redline throttle and let it break in there. Some will argue that its imperative not to drive a steady speed in the first several hundred miles of an engines life. Frankly, I tell people to drive it as they normally would and do not see any failures that I would attribute to failure to "break in"

[starchief1959]

I'd have to agree with Lohman. Just drive the car as you normally would. I wouldn't go taking it to the track right away (unless it's specifically a drag car of course) or racing the snot out of it. But I wouldn't baby it either.

[slade]

ehh, that just screams hype. i see a lot of colored text, question marks, and short sentences, but little substantial evidence. i wouldnt believe a word until i saw the results of a side by side test with two bikes, including detailed procedures, odometer readings, pictures of the pistons, and maybe dynotests.

[RRfireblade]

I have my own method.

It's worked for me for 20+ years.

I'm not telling either way.


Nowadays most modern engines don't need much if any real 'break' in. Most of that was back before high tolerance CNC machining and parts assembled more or less, in the rough.

Engines today are built tighter, with more precise methods , typically using better materials and design and are assembled in closer 'fit'.

My opinion is the 'break in' period of today is more to make sure the car or bike doesn't have any mechanical defects/flaws and you don't kill yourself doing something silly in the first week more than anything else.

[gmp211]

If it is a race motor, or you will beat up on it, Hard break-in.

Daily driver, soft.

[slade]

Nowadays most modern engines don't need much if any real 'break' in. Most of that was back before high tolerance CNC machining and parts assembled more or less, in the rough.

Engines today are built tighter, with more precise methods , typically using better materials and design and are assembled in closer 'fit'.

My opinion is the 'break in' period of today is more to make sure the car or bike doesn't have any mechanical defects/flaws and you don't kill yourself doing something silly in the first week more than anything else.

thats more or less what i would have expected, much more logical.

[Grey Goose]

I am a fan of the hard break in method. Cars which I have owned seemed to respond and perform better to being driven hard. Of course this may be a "I-know-300bps-is-300bps-but-an-autococker-is-more-accurate" thing.

On the real side, I wholesale cars and drive a LOT of same model/same year of production/same mileage cars through a given year. I can say without a doubt that cars drive differently after time. Whether this is a factor of break-in or maintenance, who knows... but I've had similarly well-maintained cars where one has more torque and redlines better than another.