Okay, lets hear some opinions on this.
Attached is an article that I have seen posted on other forums.
There does seem to be some valid points but the theory is certainly not mainstream.
What are your thoughts here?

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

well.....not sure on his theory about breakin but i guess there must be some validity to it....i mean back in my jet-ski/snowmobile/dirtbike days everytime we rebuilt an engne, all we did was mix up the first tank extra rich.....like 32:1 or so instead of the normal 50:1 and ran it hard just like its been running for years. Never had any failures other then our own stupidity for forgetting to tighten something up!

Coming from a family with a fairly successful racing history in cars, boats and sleds, I was ALWAYS told to break it in like you are racing it AFTER it had ample time to get to proper temperature and some additional oil in the mix or put some oil in the tank if it was injected for the first tank full. I have always done so and NEVER had a problem. I am sure many opinions will be presented, but for me what mototune said has worked for me!

When I was a kid I worked in a bike shop, Triumphs, BSA, Suzuki, Bultaco, Hodaka.........We put new bikes in service and then ride them about a mile from the shop to a back road with a two mile straight. We'd run those things flat out in the first 15 minutes of their life and then listen to the sales guys telling the customer about the never ending "break in". The BSA Rocket 3's would never build power if ya didn't run the crap out of em right away. I've always done the same thing with my Yamaha outboards, the break in is the time it takes me to get to open water I'm going to be "breaking in" triple new 300hp Yamaha's next week, I'll let ya know how it goes

BTW how much time is on a dyno'd motor before it's doing it's first " pull " ?

my cousin has a 21' superboat and just put a new merc 225 on it at the beginning of the summer...he called merc racing and asked what the proper break in it...they told him to run it real hard...put the trim all the way down and plow...heat up the engine...they said that people think they have to baby it, but in reality run the **** out of it...he did that and has had no problems whatsoever, and now he doesnt think twice about running wide open throttle for 30-45 min...we were hesitant to run it hard, but so far so good

Justin

I agree with Shane. After it has warmed up, drive it like you stole it!

I've always brought em' up to temp and nailed it . Broke one in at Laud. last weekend....

I recently broke in a pair of 300X's on a new 24ft Liberator cat. The break-in instructions said to run it 4500-5400rpms for the 1st hour. DO NOT idle more than 5 minutes in the entire hour! The rev limit is set at 5400 for the 1st hour or so. I was trying to break it in for a customer in a 1 1/2 mile long lake. Well, 5400 rpm was 99 mph! I went around and around this lake for 1 hour and 15 minutes and went 88 miles on the GPS. It's run great ever since and is now in upstate NY. I love beatin the crap out of a boat!

Warm it up, check the gauges and see how many RPM's you can get out of it has always worked for me. Drive it like you stole it.
Have never had powerhead problems due to wear or break in problems, the only powerhead I've lost was due to a plugged jet in a carb.

Caleb