New Engine Break-In: Truth vs. Tradition

[pa-outdoorsman]

All right folks, here's a topic I hope will generate some lively discussion and also prove beneficial to guys like me who hope to own a new scoot soon.

What is the proper technique for engine break-in, and why is it necessary? Are you really not supposed to run at full throttle for a certain period? If so, why? And for how many miles? Is it truly necessary? What is the benefit of following it, or the harm caused if it is ignored?

What about changing speeds/RPMs regularly as you drive? This is another piece of advice I have heard. Again, why?

Finally, does "conventional wisdom" in terms of engine break-in still apply to today's modern, EFI engines with super tight tolerances, or is a relic of the dirty carb era?

Since there are many folks on this page with a lot of technical knowledge and time under a bike, I'd truly appreciate your thoughts on this topic and thank you in advance for sharing!

[Kansas kymco]

There is information in the owners manual about break in procedure.  I would tend to beleive what they recomend over speculation.  That said I doubt many follow the recommendations.  I beleive most people ride it like they would normally drive it from day one.   The only thing I do is change the break in oil after a couple of hundred miles to flush the engine.  Carburetors vs FI make no difference and are not dirty emissions or mpg would be significantly worse. FI solves a lot of issues but adds complexity and cost.  Tight tolerances are more likely to cause a engine to seize up in extreme heat. 

[CROSSBOLT]

What KK said...

[Ruffus]

@pa-outdoorsman,
having been an industrial development engineer for most of my professional life in many countries, l would say so:
-motors (particularely gas, diesel, LPG, HOxygen, etc) are developed and machined nowadays with highly precise computer-steered devices.
For this and mostly cost-efficiency reason you as developer are in between this shear.
On one side you are able to produce top quality on the other side you have to see production costs.
And there is this warranty  and safety issue for producers.

But coming to quality and breaking in.
-bearings and bearing carrying surfaces are best when freshly out of the factory. Compare old/new bearing or a glide bearing surface in a motor.
-yes, there will be a certain wear and tear, 'cause different materials (cast iron, alu, plastic) have different expansion coeffizients.
(i.g. only your pistons rings are made from cast iron, alu and a hight tech coil-spring)
Therefore you will have at a new motor some metal-shavings in your first oilchange. Most companies recommand this first change after a couple of hundred kilometers or 50 hours of running.
- From this you might see why it would not be
smart to force an engine whatever from start to full performance, especially cold and with lightly off valve-clearance.
- Industrial motors have to function 100% percent from day one, or you got a problem.
-Modern oils and additives helped a lot o achieve this. Good synt oil for your scoot will help too.

But as Kansas said, most of drivers/riders don't bother to read any manual, understand and follow instructions written down there.
Got a little bit lenghty, but...

[Stig / Major Tom]

Each of the four scooters I've owned (Honda, Suzuki, Kymco, Piaggio) have at least a few words on the break-in procedure in the owner's manual.

I follow the manual.
Why?
Because - I paid good money for a new scooter.

Except:
I am embarrassed to admit that there is one conspiracy theory which I've bought into, that: "the Asians who assemble my engine and gear case have used oil derived from smashed fish-heads. Or worse, And probably mixed with a little salt water from the Pacific."

So - I quickly change it out for something with a brand name from my auto-parts store, or motorcycle shop - paying attention to the specs in the manual.

Stig

[Kansas kymco]

Each of the four scooters I've owned (Honda, Suzuki, Kymco, Piaggio) have at least a few words on the break-in procedure in the owner's manual.

I follow the manual.
Why?
Because - I paid good money for a new scooter.

Except:
I am embarrassed to admit that there is one conspiracy theory which I've bought into, that: "the Asians who assemble my engine and gear case have used oil derived from smashed fish-heads. Or worse, And probably mixed with a little salt water from the Pacific."

So - I quickly change it out for something with a brand name from my auto-parts store, or motorcycle shop - paying attention to the specs in the manual.

Stig

You could be on to something Stig, I know people who purchase a Russian built Ural sidecar/bike change the animal products oil in them. Flushing the machinings out of the new engine is a good thing.

[Ruffus]

Good points, about this fish-head mix.
But if you consider, that crude-oil is exactely produced from dead animals, well skaken up and branded to be sold to us as high tech product.😉

[JJJoseph]

Good points, about this fish-head mix.
crude-oil is exactely produced from dead animals

"dead fish & dead animals"?? I'm not so sure where some of you guys went to school, but I'm getting some hints from your profiles!  FWIW, I change the factory break-in oil at 500km & 1000km, then every 1000km forever after.  Oil is cheap, and small=frame Kymcos only use .7 litres.  That's about $2 if you're counting pennies!

[Ruffus]

@JJJoseph, 😅
was not meant  that serious, this fish head issue, l guess.

But seriousely now, at times when l was responsible for an overseas plant, and therein a couple of, let's say standalone "brakeshoe assambling lines" which each of them had a lenght of appr. 210 meters, hight of around 8 meters and 6 meters wide, l tried to get the best available lubrications in as possible.
There where/are external oil tanks/sumps of 800 liters to have the chance for maintenance without stopping production.
Costs of POL were only a minuscule bullet at the bill.

I personally think, standart factory oil which was/is filled by CHANGZHOU  KWANG YANG MOTOR CO, is not worse than any other brand available in EU or Asia or USA.
I might guess again, but this company buys any good brand motor oil for less than $200,- a barrel of 200 liters. And they check delivered quality like l did!
Coming back to breaking in:
Yes, there should be a change after appr. 500 klicks to
 your favourite brand as long as it matches closely motor producers guidelines. But not for being a low quality stuff, but for getting abrasive particles out of circulation.
And Yes again, changing oil every 1000 km will keep our pride and joy healthy.

[Kansas kymco]

"dead fish & dead animals"?? I'm not so sure where some of you guys went to school, but I'm getting some hints from your profiles!  FWIW, I change the factory break-in oil at 500km & 1000km, then every 1000km forever after.  Oil is cheap, and small=frame Kymcos only use .7 litres.  That's about $2 if you're counting pennies!

Talk to a Ural owner the gear lube they use is NOT petroleum based. You can look up what crude oil in the ground is made from before it is extracted and refined into various petroleum products. I  would put my knowledge of petroleum- refining,  product specifications and distribution against yours.

I do agree the small quantity they use is it cost very little to use  a  quality oil.

[de dee]

  my break ins "  by moto USA  2011 downtown 300i ,. ride to a steep hill near home  1 mile long ,  rev motor and WOT to top of hill,  ride to turn around , hit top of hill at red line, 70 MPH close throttle till bottom of hill,  do this for 25 miles, go home and change oil,  Reg oil ,  do same thing again till 50 miles change oil.  then ride like tom ,  then change oil every 1000, Km.s then go to dealer for the 600 Km. change ,
  used yager 2009  14,000 Km.s   did same thing   
  new Piaggio B V 350, 3 Km.s  noticed dealer put full sysn, oil in new scooter, trailord scoot home,  and rode to my hill ,  did the break in USA style,  comming back from Boston,  on a nice hill I went over 100 MPH for a short ride, then speed limit home to canada,