Soon to be putting my motor back together and I would like some educated opinions on the best break in procedure. Thanks

 

From all my home work.. checked compression... should have been 195.. checked it 180 both... went out an did 30-60 10 times (3ed gear). Rechecked compression 195 both cylinders,rings set... an have never looked back...

 

For both of my builds I put on 500-600 miles with non-synthecic oil running the bike not to exceed 4500RPM, while cruising would occasionally run up to 3500RPM. Varied RPM during rides. Compression was good 195-200ish after about 300 miles. Did a service to synthetic, got tuned and was done. I think the big thing is not to ride it like you stole it until the rings have a chance to set.

 

You're gonna find 'educated opinions' all over the chart. I followed the moto-tune method (also recommended by a local highly respected indy mechanic) for my 2010 FXD....dino oil, warm engine, run up to about 60 mph in 3rd gear, decelerate by letting off the throttle, then doing the whole thing over and over about 15 times or so. Then change oil at 100 miles, 500 miles, and then switch to synthetic (all 3 holes) at 1000 miles. Does it work? I have a friend now at about 80 K that followed the technique, and he doesn't use a drop of oil between 5K engine oil changes, and still has excellent bleed down compression. Will it work for me? Don't yet know, only at 3K, but doesn't use any oil. Hoping for the best!

The dealership will tell you 'easy does it', and maybe that works just fine too! Maybe these engines are well built enough to survive a wide range of break-in methods.

 

In a past life my profession was engine rebuilding, granted it was automotive, but the same principles apply.
I always advised people to break it in like they were going to drive. If you baby a motor during the break in period and then start jumping on it, you will stress the motor. Change the oil after 500 miles to rid it of any break in shavings, then again after another 1000 miles.
I learned this method from numerous engine rebuilders when I was training and have always followed it.
Ever notice how if you drive at a certain speed on the freeway the vehicle will tend to settle in at that speed even without trying to?

 

Mine has about 40 miles on it. Just got it back from getting it dyno tuned. I did two heat cycles at home and let them do the rest. The last build they broke in for me looked great!

 

You dyno tuned with less than 40 miles on the motor?

 

Yep, almost 100% sure it has less than 100 miles on it.

They place that tuned it builds engines all the time. They specialize in dyno tuning. I really doubt they would do anything to my fresh build that they wouldnt do on their own. They are a very well known shop recommended by my head guy. The last build I did was done the same way. Cylinders looked new after 7k hard miles.

 

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here ya go. This is how I have always done this.

hope I don't leave anything out.

.........But, better done on a dyno by a trusted tuner........

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1.
Prime the oiling system by cranking the bike with the plugs out.
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(need to see oil pressure)
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Start the motor, look for leaks,
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Run the bike for as short of a period as possible, just a minute or two max.

2.
first ride out, allow the bike to warm up by way of some light riding,
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5 mi or so on my way to an area safe to do my WOT pulls.
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Once the bike is up to temp, begin my WOT pulls,
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3rd gear, from 1500-2000rpms up to 4000,
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coast down (motor braking) to 2000 or so
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and then repeat, 8-10 times.

3.
Stop and let the bike cool.
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After the bike has cooled, take another ride, avoiding constant speeds and rpms.
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Accumulate 50miles or so and change the oil.

4.
Ride moderately for 200mi and again change the oil.
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below is from Kevin Baxter.. HeadQuarters..
http://hqperformance.blogspot.com/
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On many occasions over the past couple years I've heard the term "break in map".
I've never really understood what this meant so I decided to ask around.
I was really surprised at the answers I got...
the most common was "I like to run it richer during break in so the engine won't overheat".
This, under no terms, is the correct way to break in an engine.

As I've said before on this blog, I'm not here to debate how to do engine break in.
There are dozens of opinions but I will say confidently, running it rich in the beginning is not the way to do it.
Doing so will permanently damage the engine causing power loss you will never get back.
The idea is to run the engine as little as possible to get close to a proper desired a/f ratio so nothing is damaged,
then run it hard during the break in once you achieve that desired ratio.
Outling break in procedure is important to explain why rich mixtures during break in is a critical mistake.

Here's why...

The piston ring seal is really what the break in process is all about.
Contrary to popular belief, piston rings don't seal the combustion pressure by spring tension.
Ring tension is necessary only to "scrape" the oil to prevent it from entering the combustion chamber.
If you think about it, the ring exerts maybe 5-10 lbs of spring tension against the cylinder wall.
How can such a small amount of spring tension seal against thousands of PSI (Pounds Per Square Inch) of combustion pressure ??
It can't.

So how Do Rings Seal Against Tremendous Combustion Pressure ??

Rings seal against the combustion pressure from the actual gas pressure itself.
It passes over the top of the ring, and gets behind it to force it outward against the cylinder wall...
which is why they are beveled.
The problem is that new rings are far from perfect and they must be worn in in order to completely seal all the way around the bore.
If the gas pressure is strong enough during the engine's first miles of operation
(as in WOT),
then the entire ring will wear into the cylinder surface,
to seal the combustion pressure as well as possible.

The Problem With "Easy Break In" ...
The honed crosshatch pattern in the cylinder bore acts like a file to allow the rings to wear.
The rings quickly wear down the "peaks" of this roughness,
regardless of how hard the engine is run.
There's a very small window of opportunity to get the rings to seal really well ...

the first 20 miles.

If the rings aren't forced against the walls soon enough,
they'll use up the roughness before they fully seat.
Once that happens there is no solution other than bore, new rings/pistons, and start over.

What compounds the problem is the overly rich fuel mixture I mentioned above.
The rich fuel mix will dilute the oil.
Dilute the oil too much and you'll wash the oil from the cylinder walls
because the rings aren't seated and fit tightly to prevent the mix from staying above the top ring.
Remember the rings aren't sealed in the beginning,
so the raw fuel washes down the cylinder and piston skirt.
When you do that, you accelerate the wear on the ring and cylinder wall before the ring has time to seal...
then you don't build the cylinder pressures you should
and the engine will NEVER reach its full power potential....EVER.

Happy Motoring!
Kevin

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I guess what I am mostly trying to say is that alot of people put way too much thought into the break in process.