New Engine/Rebuilt Engine Break In Procedure

[Lion]

Fellow bikers and riders, I have found this interesting article regarding the break in procedure of your new bike or rebuilt bike. Feel free to share your opinions and experience.

 

I as a new bike owner would also like to know what and how is the best way to break in the new engine with optimum results.

 

New or Rebuilt Engine Break-in Procedure

 

A recommended engine break-in procedure.

This is a summation of many articles on the subject found on the internet. Some of the information is from MOTORCYCLIST Feb. 1991, titled GIVE IT A BREAK-IN (How to make your bike run stronger and live longer), and some is from a Textron Lycoming "Key Reprint" article.

 

The first few hundred miles of a new engine's life have a major impact on how strongly that engine will perform, how much oil it will consume and how long it will last. The main purpose of break-in is to seat the compression rings to the cylinder walls. We are talking about the physical mating of the engine's piston rings to it's corresponding cylinder wall. That is, we want to physically wear the new piston rings into the cylinder wall until a compatible seal between the two is achieved.

 

Proper engine break in will produce an engine that achieves maximum power output with the least amount of oil consumption due to the fact that the piston rings have seated properly to the cylinder wall. When the piston rings are broken in or seated, they do not allow combustion gases to escape the combustion chamber past the piston rings into the crankcase section of the engine. This lack of "blow-by" keeps your engine running cleaner and cooler by preventing hot combustion gases and by-products from entering the crankcase section of the engine. Excessive "blow-by" will cause the crankcase section of the engine to become pressurized and contaminated with combustion gases, which in turn will force normal oil vapors out of the engine's breather, causing the engine to consume excessive amounts of oil.

In addition to sealing combustion gases in the combustion chamber, piston rings must also manage the amount of oil present on the cylinder walls for lubrication. If the rings do not seat properly, they cannot perform this function and will allow excessive amounts of oil to accumulate on the cylinder wall surfaces. This oil is burned each and every time the cylinder fires. The burning of this oil, coupled with "blow-by" induced engine breathing, are reasons that an engine that hasn't been broken in will consume more than its share of oil.

 

When a cylinder is new or overhauled the surface of it's walls are honed with abrasive stones to produce a rough surface that will help wear the piston rings in. This roughing up of the surface is known as "cross-hatching". A cylinder wall that has been properly "cross hatched" has a series of minute peaks and valleys cut into its surface. The face or portion of the piston ring that interfaces with the cross hatched cylinder wall is tapered to allow only a small portion of the ring to contact the honed cylinder wall. When the engine is operated, the tapered portion of the face of the piston ring rubs against the coarse surface of the cylinder wall causing wear on both objects.

Each tiny groove acts as the oil reservoir holding oil up to the top level of the groove where it then spreads over the peak surface. The piston ring must travel up and down over this grooved surface, and must "hydroplane" on the oil film retained by the grooves. Otherwise, the ring would make metal-to-metal contact with the cylinder wall and the cylinder would quickly wear out.

 

 

However the ring will only ride on this film of oil if there is sufficient surface area to support the ring on the oil. When the cylinders are freshly honed the peaks are sharp with little surface area. Our goal when seating the rings on new steel cylinders is to flatten out these peaks to give more surface area to support the rings, while leaving the bottom of the groove intact to hold enough oil to keep the surface of the cylinder wet with oil. See illustration. At the point where the top of the peaks produced by the honing operation become smooth and the tapered portion of the piston ring wears flat break in has occurred.

 

When the engine is operating, a force known as Break Mean Effective Pressure or B.M.E.P is generated within the combustion chamber. B.M.E.P. is the resultant force produced from the controlled burning of the fuel air mixture that the engine runs on. The higher the power setting the engine is running at, the higher the B.M.E.P. is and conversely as the power setting is lowered the B.M.E.P. becomes less.

B.M.E.P is an important part of the break in process. When the engine is running, B.M.E.P. is present in the cylinder behind the piston rings and it's force pushes the piston ring outward against the coarse honed cylinder wall. Piston rings are designed to take advantage of the pressure and us it to push the rings out against the cylinder wall. Therefore, as pressure builds during the compression stroke, the rings are pushed harder against the cylinder wall which aids in seating the rings.

 

The higher the B.M.E.P, the harder the piston ring is pushed against the wall. The surface temperature at the piston ring face and cylinder wall interface will be greater with high B.M.E.P. than with low B.M.E.P. This is because we are pushing the ring harder against the rough cylinder wall surface causing high amounts of friction and thus heat. The primary deterrent of break in is this heat. Allowing to much heat to build up at the ring to cylinder wall interface will cause the lubricating oil that is present to break down and glaze the cylinder wall surface. This glaze will prevent any further seating of the piston rings. If glazing is allowed to happen break in will never occur. Also, if too little pressure (throttle) is used during the break-in period glazing will also occur.

 

Most people seem to operate on the philosophy that they can best get their money's worth from any mechanical device by treating it with great care. This is probably true, but in many cases it is necessary to interpret what great care really means. This is particularly applicable when considering the break-in of a modern, reciprocating engine.

For those who still think that running the engine hard during break-in falls into the category of cruel and unusual punishment, there is one more argument for using high power loading for short periods (to avoid excessive heat) during the break-in. The use of low power settings does not expand the piston rings enough, and a film of oil is left on the cylinder walls. The high temperatures in the combustion chamber will oxidize this oil film so that it creates glazing of the cylinder walls. When this happens, the ring break-in process stops, and excessive oil consumption frequently occurs. The bad news is that extensive glazing can only be corrected by removing the cylinders and rehoning the walls. This is expensive, and it is an expense that can be avoided by proper break in procedures.

 

We must achieve a happy medium where we are pushing on the ring hard enough to wear it in but not hard enough to generate enough heat to cause glazing. Once again, if glazing should occur, the only remedy is to remove the effected cylinder, re-hone it and replace the piston rings and start the whole process over again.

 

We asked four top motorcycle engine builders what they do to ensure peak power output and optimum engine life. Here is a capsulation of their responses.

 

"If the wrong type of oil is used initially, or the break-in is too easy, rings and cylinders could (read will) glaze and never seal properly. A fresh cylinder wall needs some medium to high engine loading to get the piston rings to seat properly for good compression but make sure you don't lug or overheat the engine. Use high quality, low viscosity oil (Valvoline 30 weight), no synthetics, too slippery. If synthetics are used during initial break in the rings are sure to glaze over.

 

An engine's initial run should be used to bring oil and coolant (air, oil, and/or water) up to operating temperature only, with little or no load, then shut down and allowed to cool to ambient temperature. This is important. After each run the engine needs to completely cool down to ambient temperature. In Texas, especially in the summer, that's still pretty hot. After a cool down period, start it up again and take the motorcycle for it's fist ride (you hope).

This time give the engine light loads at relatively low rpm and stay out of top gear. Lugging the engine, i.e., low RPM with a lot of throttle (manifold pressure), is more detrimental than high rpm. Another key is too constantly vary engine load during the entire break-in period. A constant load is not ideal for breaking in bearing tolerances. This second run should last only 10-15minutes before another complete cool down.

 

The third run should see slightly higher rpm with light to medium power loading using short bursts of acceleration to help seat the rings. Again 10-15 minutes of running should do it and again avoid top gear. A forth run should consist of light to medium engine loads with a few more bursts of medium-high rpm, and lasting just 10-15 minutes varying the engine load and again avoiding top gear. Next while the engine is still warm drain the oil and change the filter. This gets out the new metal particles that are being worn away. Most of the metal particles will break away within the first 50 -75 miles. To ensure the rings seat well, use the same high quality oil and don't be shy about short duration high rpm blasts through the lower gears after the oil has been changed.

 

A few more 15-20 minute sessions should be used to work up to the engine's redline gradually increasing the engine loads. After some definite hard running and 250-500 miles it's a good idea to check the valves. After 500 miles re-torqueing the head is suggested. Switch to synthetic oil but not before 500-1500 miles. Most of the engine experts warned of the danger of breaking in the engine too easily and ending up with an engine that will always run slow whether it is from tight tolerances, inadequate ring seal or carbon buildup. Engine load is more detrimental than rpm because of the head created internally, so avoid lugging the engine but rev it freely especially in the lower gears. Basically, be sure not to get it too hot but be sure to seat the rings properly.

 

So that's it, sure a lot different than keeping under 4000 rpm for 500 miles then under 5000 rpm for 1000 miles. Maybe bike manufacturers are being super cautious at the expense of your motor's performance? I think that they take the cautious route that works over time (1000 miles, or about 20 hours of break in) versus a faster route that can be more easily screwed up."

[Lion]

This is the break in procedure of a RC-51 aka Honda VTR1000 posted up by some foreign biker. Any feedback?

 

When I break-in a bike I try to follow a very serious order of operations & so far I have had very good success with it. My last 3 new bikes have always dynoed at the upper end of the horsepower scale when compared to the same model bikes on the same dyno.

 

These are the guidelines I use for all my new bikes:

 

Lots of heat cycles! run it & let it cool off, run it & let it cool off.

 

#1 rule is never maintain a steady speed during break-in. Always keep the revs going up & down. Nothing is worse on a new bike than putting miles on it at a steady rpm especially on the interstate.

 

For the 1st 150 miles I take it real easy never exceeding 75% of the redline(i.e if redline is 10,000 then I would not go over 7500) I take extra special care to listen for as well as feel any anomalies in the valvetrain and driveline. I am also very smooth on the throttle no jerky movements or ham fisted off & ons & I never hold the throttle at the higher rpms if I go to 7500rpm I immediately shift & bring the rpms back down.

 

From 150 to 250 miles I try to liven up the process by introducing brief spurts up to 90% of the redline, but once again I never stay there immediately bring the revs back down & maybe once or twice run it to the redzone & back down but don't hit the hard limiter.

 

250 to 600 miles It's spirited riding, but still making sure to keep the rpms fluctuating & I routinely take it up to close to redline without hitting the hard limiter.

 

600 miles I change the oil & inspect it thoroughly, hell I even cut open my oil filters & look LOL

 

600-1200 miles normal riding but still with caution & smoothness in my actions & I still try to vary my rpms on the highway even though by now that's damn near impossible cause I'm usually commuting to different rides.

 

After 1200 miles I flog it, wheelies & top end bursts, but I still don't hold it wide open for any real duration of time until around 1500-1700 miles.

 

Many RC51 Owners have commented that they have followed these instructions & their personal results were right along the results I have reported in that their bikes also produced dyno charts that were at the upper end of the scale for power output of similarly or identically equipped machines. There is no guarantee that my way works nor any scientific tests to prove it, but commonsense & the dyno results should go a long way in helping you to decide what is the best way to break your bike in properly.

 

 

 

A couple other notes:

 

Yes there are professional tuners out there that recommend that you flog the hell out of the bike right from the start to instantly seat the rings etc & yes I will admit that those bikes have in many cases produced a little more peak horsepower initially, but what everyone fails to realize is that those professional race tuners are going to end up rebuilding that motor at least once if not twice a season (sometimes more often than that) & they don't care if engine wear is accelerated or not. Most of us want a reliable good performing motor & my break-in procedures will give you that. I've been doing this for many years & living in Memphis have seen many bikes bought in the afternoon & being dragraced that evening & they always end up smoking within about 1500 miles.

 

The aviation industry has without a doubt the most explicit & detailed break-in procedures for internal combustion motors. The reason for this is that they MUST be reliable as an engine failure in the air has the potential to be alot more dangerous than an engine failure on the ground. Their engine break-in regimens consist of many of the exact same key elements that mine do. Heat cycles, no initial steady rpms & ever increasing rpm peaks.

 

One final note is that even though the engine may be broke in properly many times the transmission still takes longer. It is not uncommon for a motorcycle transmission to need 1800-2000 miles to get fully broke-in & during that time is susceptible to accelerated wear just as the motors are. You may even notice that the more miles you put on your bike the better the transmission starts to work. During break-in keep your shifts solid & smooth, use the clutch for both upshifts/downshifts & just generally be aware that all new metal parts need time to bed in properly.

 

[Lion]

This is controversial... Take a break and read.

 

http://mototuneusa.com/break_in_secrets.htm

[.Hack]

This is controversial... Take a break and read.

 

http://mototuneusa.com/break_in_secrets.htm

 

The hard break in method?

[Lion]

They mentioned not using synthetic oil for breaking in process. What are the non-synthetic or mineral EO available in Singapore then? Any experienced rider knows the answer? Pls do enlighten and share.

[Lion]

The hard break in method?

 

How's the Gixxer doing? Having fun?

 

Collecting my R6 next Sat.

[.Hack]

How's the Gixxer doing? Having fun?

 

Collecting my R6 next Sat.

 

Yup, so far so good. Nice bike. Only problem is the meter which i havent solve. Wah, 08'r6??

[.Hack]

They mentioned not using synthetic oil for breaking in process. What are the non-synthetic or mineral EO available in Singapore then? Any experienced rider knows the answer? Pls do enlighten and share.

 

You mean they didnt even use mineral oil to run in?

[Lion]

Yup, so far so good. Nice bike. Only problem is the meter which i havent solve. Wah, 08'r6??

Yup, bought a new 08 R6.

 

You mean they didnt even use mineral oil to run in?

Think they run in using mineral oil. Mineral is not synthetic at all... Not even semi syn.

[.Hack]

Yup, bought a new 08 R6.

 

 

Think they run in using mineral oil. Mineral is not synthetic at all... Not even semi syn.

 

Wah.. Damn rich man.. 08'R6.. Your gf never make noise??

 

Yup, run in is using mineral oil.

[Lion]

Wah.. Damn rich man.. 08'R6.. Your gf never make noise??

 

Yup, run in is using mineral oil.

 

She dunno.

 

Nobody wants to share their experience huh?

[.Hack]

She dunno.

 

Nobody wants to share their experience huh?

 

Kaoz... Paper cannot cover fire..

But nvm lah, she know already too late, bike buy already.

 

Btw i run in using the conventional method.

[Lion]

Kaoz... Paper cannot cover fire..

But nvm lah, she know already too late, bike buy already.

 

Btw i run in using the conventional method.

 

And how is the conventional method like?

[.Hack]

And how is the conventional method like?

 

Its written in your owner's manual. Forgot the exact numbers, should be first 1000km don't exceed 4 or 5krpm. I remember i change oil very frequently for the 1st 1000km during running in since mineral oil is very cheap, around 8bucks per bottle.

[Lion]

Its written in your owner's manual. Forgot the exact numbers, should be first 1000km don't exceed 4 or 5krpm. I remember i change oil very frequently for the 1st 1000km during running in since mineral oil is very cheap, around 8bucks per bottle.

 

The posted article was saying don't follow manual break in leh... Very stress now. Dunno which is the better method.

[.Hack]

The posted article was saying don't follow manual break in leh... Very stress now. Dunno which is the better method.

 

Run in method got 2 schools of followers, one is the hard run in method, the other is conventional method. Seems that hard run in your bike will have more hp. But i still choose the conventional below 5000krpm method.

[MS]

I have worked in the automotive engineering line for years. Currently working as an engineer in a German MNC in the automotive industry.

 

There is only 1 method of recommended running in. That is the manufacturer's recommendation.

This running in issue has been a very controversial issue in this forum. But the fact is actually a very straight forward answer. Technically, there is no evidence which proved that 'hard run in' gives more power. Hard run in is merely old wives tales. I have previously met up some SBF members and convinced them on my claims with explicit explanation. A lot of people are unable to conduct proper automotive comparision tests and jump to conclusions on engine technology.

I have no wish to argue with anyone over the net on this issue. Believe it or not is up to the individual.

 

Do not believe anything you read in the net without questioning. Please refer to the manufacturers for more details on your recommended running in. They are just an email away. Check the origin of your vehicle before calling. If your bike is from Canada, contact the Canadian representative, if your engine is from UK contact the UK representative. This is because engines that run on otto cycle produced in different countries have a different compression ratio due to fuel difference. The higher the compression ratio, the higher RON number is required. The manufacturers do not recommend a running in method that will destroy their own reputation. The team who designed the engine knows the component better than any Tom d.ick and Harry who claims to be a guru.

[Lion]

I have worked in the automotive engineering line for years. Currently working as an engineer in a German MNC in the automotive industry.

 

There is only 1 method of recommended running in. That is the manufacturer's recommendation.

This running in issue has been a very controversial issue in this forum. But the fact is actually a very straight forward answer. Technically, there is no evidence which proved that 'hard run in' gives more power. Hard run in is merely old wives tales. I have previously met up some SBF members and convinced them on my claims with explicit explanation. A lot of people are unable to conduct proper automotive comparision tests and jump to conclusions on engine technology.

I have no wish to argue with anyone over the net on this issue. Believe it or not is up to the individual.

 

Do not believe anything you read in the net without questioning. Please refer to the manufacturers for more details on your recommended running in. They are just an email away. Check the origin of your vehicle before calling. If your bike is from Canada, contact the Canadian representative, if your engine is from UK contact the UK representative. This is because engines that run on otto cycle produced in different countries have a different compression ratio due to fuel difference. The higher the compression ratio, the higher RON number is required. The manufacturers do not recommend a running in method that will destroy their own reputation. The team who designed the engine knows the component better than any Tom d.ick and Harry who claims to be a guru.

 

Now that is what i called enlightening...

[.Hack]

Great explaination and info their by MS.

[Non Stop Racing]

never too late to do a search

 

http://www.singaporebikes.com/forums/showthread.php?t=145171

 

http://www.singaporebikes.com/forums/showthread.php?t=100508&highlight=Hard+break

 

this topic was heatly debate before. mostly of two minded. 1 who against hardbreak in , one who support it. do your research and choose .. but some how in all the thread of such topic,theres alway a pop out - im a enigneer here n there, im working automotive line bah bah. no offence ,just find too much of a conicidence. hehe . enjoy .

[MS]

never too late to do a search

 

http://www.singaporebikes.com/forums/showthread.php?t=145171

 

http://www.singaporebikes.com/forums/showthread.php?t=100508&highlight=Hard+break

 

this topic was heatly debate before. mostly of two minded. 1 who against hardbreak in , one who support it. do your research and choose .. but some how in all the thread of such topic,theres alway a pop out - im a enigneer here n there, im working automotive line bah bah. no offence ,just find too much of a conicidence. hehe . enjoy .

 

well.. I said previously its up to the individual to believe or not. And I have also explained the reasons on why the owner should listen to the manufacturer rather than merely old wives tales.

 

Those people who know me personally know my credentials in the industry. And some happen to be in the forum too. By highlighting it somehow creates a certain degree of reliability. And naturally there will be some who cannot accept it when being told off by a member of the industry. This is something that cannot be avoided and I am getting used to it. But I prefer to remain anonymous in regards to the company I represent.

 

It is not offensive to highlight the points you raised. Rather it has acted as an induction for people to think deeper on the things they read on the internet which I am encouraging. If anyone is unsure, just refer back to the vehicle builder and not on anything they read on the internet.

 

Thanks for your points raised. It has definately saved my trouble by speaking my mind in my place.

[Lion]

well.. I said previously its up to the individual to believe or not. And I have also explained the reasons on why the owner should listen to the manufacturer rather than merely old wives tales.

 

Those people who know me personally know my credentials in the industry. And some happen to be in the forum too. By highlighting it somehow creates a certain degree of reliability. And naturally there will be some who cannot accept it when being told off by a member of the industry. This is something that cannot be avoided and I am getting used to it. But I prefer to remain anonymous in regards to the company I represent.

 

It is not offensive to highlight the points you raised. Rather it has acted as an induction for people to think deeper on the things they read on the internet which I am encouraging. If anyone is unsure, just refer back to the vehicle builder and not on anything they read on the internet.

 

Thanks for your points raised. It has definately saved my trouble by speaking my mind in my place.

 

Dude, by sharing your views and information, you are much appreciated. I have decided to run-in my new bike with conventional method.

[MS]

Dude, by sharing your views and information, you are much appreciated. I have decided to run-in my new bike with conventional method.

 

no problem dude.

This is your bike and your money. You should have the rightful ownership and decision on how to deal with your vehicle. I am merely offering my advise since it's in line with my profession.

If you're interested with stuffs in the automotive industry regardless of technical stuffs, you can PM me. I am sure there are things which I don't know and you know.