The Break-In Game
#1
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Here's an article from the late-great Gordon Jennings that I learned a lot from. Enjoy!:
The Break-In Game, article by Gordon Jennings, Cycle Magazine, May 1997
Two questions have plagued my life as a motojournalist: The first is, "I'm thinking of getting a motorcycle. What shall I buy?" Then comes the second: "How should I break in my new motorcycle?" No satisfactory answer exists for the first question, as preference in such matter is so individual. I don't know anyone well enough to choose a motorcycle for them.
Giving break-in advice is much less dangerous and it's more in my line of work. I believe I can add to the scanty information provided by most owner's manuals. These manuals typically admonish owners to keep engine speed below a certain level and/or refrain from using full throttle. They don't say why the limits are necessary, or what damage might result from non-compliance.
Fortunately for all of us, motorcycle manufacturers have done a lot to solve the special problems of parts beginning life in service.
Their built-in solutions to those problems are so good your new bike's moving parts will settle into peaceful coexistence without much help from you, as speed crazed motojournalists know from long, shameful experience.
New motorcycles delivered into the unkind hands of magazine test riders get no help at all. Careful break-in for most magazine test bikes means no wide-open, red-line running until there are three digits [if that—Ed.] showing on the odometer. That is not a good procedure to follow with a new motorcycle you own and will have to repair if it breaks. But, the fact that 30-plus years of new models have survived magazine guys' abuse speaks volumes for motorcycles' quality.
For the purposes of discussion, I'm going to assume you'd prefer to ease your new motorcycle through its break-in period undamaged. Your best chance of attaining this goal lies in understanding what's happening during those crucial first 500 to 1000 miles.
The tenderest of all new or newly rebuilt engine's tender points is at the scrubbing contacts between rings and cylinder bores.
Actually, it's the top compression ring that gets the big load because it uses pressure on the upper cylinder for its sealing action. Gas pressure above the piston pushes the compression ring down against the bottom of its groove and out against the cylinder wall.
With gas pressure in the upper cylinder at 500 pounds per square inch or even more at part throttle, the load on the oil film separating
ring and cylinder wall is also 500psi. If the ring gets past the oil and into direct contact with the cylinder, friction heating will cause melting at the contact point.
What happens next with plain iron rings is that a tiny bead of melted metal from the cylinder becomes welded to the ring's contact face.
The bead, traveling with the ring, then picks up more metal from the cylinder until it grows too large and breaks away from the ring.
Once this separation occurs, the built-up metal particle scores the piston skirt before migrating down to the crankcase, where it does more damage until captured by the oil strainer.
Advances in piston ring technology remove most of the dangers from the break-in period. Today's new engines have their top rings faced with chromium or molybdenum, metals that do not readily friction-weld to an iron cylinder wall. The worst you get from a chrome- or moly-coated ring scrubbing roughness from the cast-iron cylinder bore are some small scratches.
Case iron, of the kind used in cylinders, has a porous microstructure that readily wets with oil and then retains it fairly well. It has
the further advantage of containing numerous small graphite particles, which are themselves a lubricant. Despite these favorable factors it is still necessary to finish the cylinder bore with a relatively coarse-stone hone moved up and down as it spins to make cross-hatched scratches, which hold oil on the cylinder walls and help control oil consumption.
When you're building a racing engine you can finish-hone the bores to be so smooth they don't need a breaking-in. You can't do that in
street-engines, as the smooth bores would soon become polished, and a little roughness is required for oil control. The small volume of
gases cross-hatching leaks past the compression ring, moves oil down to the oil ring, then blows it through the oil return holes to the crankcase. In my racing days, I attempted to raise an engine's compression ratio by heli-arc welding more aluminum to the pistons' crowns. I tested the concept on an old piston, one I carefully measured before adding metal and was gratified to find negligible distortion after the welding. Alas, when I performed the same operation on a new piston it distorted so much down at the skirt as to be utterly unusable.
On a hunch, I placed an old piston and a new one on a tray and slid them into a 500-degree F oven, leaving them in for 30 minutes. The old piston came out of the oven just as it had gone in, but the new piston was badly warped. I should have anticipated this, as complex castings and forgings like pistons end up with a lot of locked-in stresses by the time the manufacturing process is completed.
A new piston's internal stresses are relaxed by heating, and if this occurs with the piston in an oven, but otherwise unrestrained, the metal squirms like mad and ends up distorted. The same piston, closely confined in a cylinder, will take on a shape much better suited to its surroundings. It is not surprising that this should be the case, as even after break-in the pistons in a running engine are a light-interference fit in their bores. Only the oil film between them and cylinders' walls prevents seizing.
Given time, your new motorcycle's pistons will adjust to life of whizzing up and down in cylinders. Heating will relax the locked-in
stresses, and confinement will keep them from warping into aluminum pretzels. Repeated cycles of heating and cooling, as occur when you
ride your new motorcycle and then park it for the night, work the pistons into shape, but they have to be treated with consideration
while still new and nervous. If you pay heed to the advice given in your owner's manual, those pistons will settle in without having
their skirts scuffed or distorted. The rings will appreciate it, too, and if you treat your new motorcycle with enough consideration
to keep the pistons and rings healthy, you won't do any damage to other vulnerable bits, like bearings, gears, and cam followers.
You'll avoid post-break-in engine damage by avoiding a couple of things too many riders have made habit. Do not ever, ever zing a cold engine up to high revs, as this will pound in the pistons' skirts before you can moan "engine rebuild." The other bad habit is the lengthy warm-up, which just prolongs the period in which acids
condense on cold cylinder walls and eat at everything. Fire it up, ride away just be gentle with it until it's warm and ready to roar.
One last thing: Give yourself a little time to become accustomed to that new motorcycle. There's nothing more depressing than throwing your brand-new bike down the road. –Gordon Jennings, May 1997
The Break-In Game, article by Gordon Jennings, Cycle Magazine, May 1997
Two questions have plagued my life as a motojournalist: The first is, "I'm thinking of getting a motorcycle. What shall I buy?" Then comes the second: "How should I break in my new motorcycle?" No satisfactory answer exists for the first question, as preference in such matter is so individual. I don't know anyone well enough to choose a motorcycle for them.
Giving break-in advice is much less dangerous and it's more in my line of work. I believe I can add to the scanty information provided by most owner's manuals. These manuals typically admonish owners to keep engine speed below a certain level and/or refrain from using full throttle. They don't say why the limits are necessary, or what damage might result from non-compliance.
Fortunately for all of us, motorcycle manufacturers have done a lot to solve the special problems of parts beginning life in service.
Their built-in solutions to those problems are so good your new bike's moving parts will settle into peaceful coexistence without much help from you, as speed crazed motojournalists know from long, shameful experience.
New motorcycles delivered into the unkind hands of magazine test riders get no help at all. Careful break-in for most magazine test bikes means no wide-open, red-line running until there are three digits [if that—Ed.] showing on the odometer. That is not a good procedure to follow with a new motorcycle you own and will have to repair if it breaks. But, the fact that 30-plus years of new models have survived magazine guys' abuse speaks volumes for motorcycles' quality.
For the purposes of discussion, I'm going to assume you'd prefer to ease your new motorcycle through its break-in period undamaged. Your best chance of attaining this goal lies in understanding what's happening during those crucial first 500 to 1000 miles.
The tenderest of all new or newly rebuilt engine's tender points is at the scrubbing contacts between rings and cylinder bores.
Actually, it's the top compression ring that gets the big load because it uses pressure on the upper cylinder for its sealing action. Gas pressure above the piston pushes the compression ring down against the bottom of its groove and out against the cylinder wall.
With gas pressure in the upper cylinder at 500 pounds per square inch or even more at part throttle, the load on the oil film separating
ring and cylinder wall is also 500psi. If the ring gets past the oil and into direct contact with the cylinder, friction heating will cause melting at the contact point.
What happens next with plain iron rings is that a tiny bead of melted metal from the cylinder becomes welded to the ring's contact face.
The bead, traveling with the ring, then picks up more metal from the cylinder until it grows too large and breaks away from the ring.
Once this separation occurs, the built-up metal particle scores the piston skirt before migrating down to the crankcase, where it does more damage until captured by the oil strainer.
Advances in piston ring technology remove most of the dangers from the break-in period. Today's new engines have their top rings faced with chromium or molybdenum, metals that do not readily friction-weld to an iron cylinder wall. The worst you get from a chrome- or moly-coated ring scrubbing roughness from the cast-iron cylinder bore are some small scratches.
Case iron, of the kind used in cylinders, has a porous microstructure that readily wets with oil and then retains it fairly well. It has
the further advantage of containing numerous small graphite particles, which are themselves a lubricant. Despite these favorable factors it is still necessary to finish the cylinder bore with a relatively coarse-stone hone moved up and down as it spins to make cross-hatched scratches, which hold oil on the cylinder walls and help control oil consumption.
When you're building a racing engine you can finish-hone the bores to be so smooth they don't need a breaking-in. You can't do that in
street-engines, as the smooth bores would soon become polished, and a little roughness is required for oil control. The small volume of
gases cross-hatching leaks past the compression ring, moves oil down to the oil ring, then blows it through the oil return holes to the crankcase. In my racing days, I attempted to raise an engine's compression ratio by heli-arc welding more aluminum to the pistons' crowns. I tested the concept on an old piston, one I carefully measured before adding metal and was gratified to find negligible distortion after the welding. Alas, when I performed the same operation on a new piston it distorted so much down at the skirt as to be utterly unusable.
On a hunch, I placed an old piston and a new one on a tray and slid them into a 500-degree F oven, leaving them in for 30 minutes. The old piston came out of the oven just as it had gone in, but the new piston was badly warped. I should have anticipated this, as complex castings and forgings like pistons end up with a lot of locked-in stresses by the time the manufacturing process is completed.
A new piston's internal stresses are relaxed by heating, and if this occurs with the piston in an oven, but otherwise unrestrained, the metal squirms like mad and ends up distorted. The same piston, closely confined in a cylinder, will take on a shape much better suited to its surroundings. It is not surprising that this should be the case, as even after break-in the pistons in a running engine are a light-interference fit in their bores. Only the oil film between them and cylinders' walls prevents seizing.
Given time, your new motorcycle's pistons will adjust to life of whizzing up and down in cylinders. Heating will relax the locked-in
stresses, and confinement will keep them from warping into aluminum pretzels. Repeated cycles of heating and cooling, as occur when you
ride your new motorcycle and then park it for the night, work the pistons into shape, but they have to be treated with consideration
while still new and nervous. If you pay heed to the advice given in your owner's manual, those pistons will settle in without having
their skirts scuffed or distorted. The rings will appreciate it, too, and if you treat your new motorcycle with enough consideration
to keep the pistons and rings healthy, you won't do any damage to other vulnerable bits, like bearings, gears, and cam followers.
You'll avoid post-break-in engine damage by avoiding a couple of things too many riders have made habit. Do not ever, ever zing a cold engine up to high revs, as this will pound in the pistons' skirts before you can moan "engine rebuild." The other bad habit is the lengthy warm-up, which just prolongs the period in which acids
condense on cold cylinder walls and eat at everything. Fire it up, ride away just be gentle with it until it's warm and ready to roar.
One last thing: Give yourself a little time to become accustomed to that new motorcycle. There's nothing more depressing than throwing your brand-new bike down the road. –Gordon Jennings, May 1997
#2
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i know i know i cant believe the nerve of iroc questionin the almighty chris...but its actually not his words so here goes [8D]
these questions are based off my 05 cbr so...
first off does this post apply to the newer fuel injected bikes? i only ask cause when i cold start mine it auto revs (auto chokes) at 2500-3000...nothin i can do will change this so i can either feather the clutch in and out til it warms up or just let it sit and run til it idles down(usually takes like 3 minutes or so)
second question is off that comment ...am i hurtin the bike lettin it run til it idles back down?
o and is startin the bike in cold weather that bad on it even if ur gonna ride it?
these questions are based off my 05 cbr so...
first off does this post apply to the newer fuel injected bikes? i only ask cause when i cold start mine it auto revs (auto chokes) at 2500-3000...nothin i can do will change this so i can either feather the clutch in and out til it warms up or just let it sit and run til it idles down(usually takes like 3 minutes or so)
second question is off that comment ...am i hurtin the bike lettin it run til it idles back down?
o and is startin the bike in cold weather that bad on it even if ur gonna ride it?
#3
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"Almighty"? Sheeee-it.
This article was written back in '97, back when only Bikes Made Weird (BMW's) were the only fuel-injected bikes.
I personally prefer to start the bike and let it idle at 1800rpm with the choke just long enough for me to put on helmet, gloves and dog, but Honda's engineers probably know more about the characteristics of the metal parts in your CBR, so it's probably best to trust their fuel-injection's enrichener settings.
Starting a bike in cold weather is not bad, BUT starting it and letting it idle in your garage for several minutes (instead of properly winterizing it) a few times a month is very bad, IMO. Fouled plugs, dead batteries and burnt-up starter motors are some of the symptoms we'll be reading in here soon. Fortunately we won't have to read about the shortened engine life due to over-rich idling causing the oil film on the cylinder walls to be fouled (or even rinsed away in some cases) by the excessively rich condition.
Starting the bike in cold weather isn't bad at all, but I'd take it out for a 10-mile ride each time. And if it's too cold for that, I'd get a battery tender Jr and winterize the bike.
Good luck and let us know how it goes.
Peace!
-CCinC
This article was written back in '97, back when only Bikes Made Weird (BMW's) were the only fuel-injected bikes.
I personally prefer to start the bike and let it idle at 1800rpm with the choke just long enough for me to put on helmet, gloves and dog, but Honda's engineers probably know more about the characteristics of the metal parts in your CBR, so it's probably best to trust their fuel-injection's enrichener settings.
Starting a bike in cold weather is not bad, BUT starting it and letting it idle in your garage for several minutes (instead of properly winterizing it) a few times a month is very bad, IMO. Fouled plugs, dead batteries and burnt-up starter motors are some of the symptoms we'll be reading in here soon. Fortunately we won't have to read about the shortened engine life due to over-rich idling causing the oil film on the cylinder walls to be fouled (or even rinsed away in some cases) by the excessively rich condition.
Starting the bike in cold weather isn't bad at all, but I'd take it out for a 10-mile ride each time. And if it's too cold for that, I'd get a battery tender Jr and winterize the bike.
Good luck and let us know how it goes.
Peace!
-CCinC
#4
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first off lol i just got the bmw crack....
ok really now...idk that honda engineers agree that lettin the bike run at a choke lvl idle for several minutes is what they desire or not lol all i was sayin is thats its difficult to operate my bike when its revvin 3 grand lol..
i do ride my bike 7 miles one way everyday (that its not raining/snowing/sleet or if it rains on monday alot then stays below 32 on tuesday...not a good riding day) so thats a total of 14 per day mininum atleast 4-7 days a week. the battery doesnt seem to have any troubles poppin off every morning
i obviously do respect your opinion on the matter or i wouldnt bother asking. the many years and many bikes you have owned/still own speaks volumes to me about the care/knowledge u have on them. as far as the honda engineers lemme check the manual just in case there is a foot note about it
ok really now...idk that honda engineers agree that lettin the bike run at a choke lvl idle for several minutes is what they desire or not lol all i was sayin is thats its difficult to operate my bike when its revvin 3 grand lol..
i do ride my bike 7 miles one way everyday (that its not raining/snowing/sleet or if it rains on monday alot then stays below 32 on tuesday...not a good riding day) so thats a total of 14 per day mininum atleast 4-7 days a week. the battery doesnt seem to have any troubles poppin off every morning
i obviously do respect your opinion on the matter or i wouldnt bother asking. the many years and many bikes you have owned/still own speaks volumes to me about the care/knowledge u have on them. as far as the honda engineers lemme check the manual just in case there is a foot note about it
![Big Grin](https://www.kawasakiforums.com/forum/images/smilies/biggrin.gif)
#5
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here is an interesting article regarding engine break in that ive seen posted a few places
http://www.mototuneusa.com/break_in_secrets.htm
http://www.mototuneusa.com/break_in_secrets.htm
#6
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That little smiling dufus with the glasses always seems to come up whenever the breaking-in new engines is brought up.
He says plenty about "myths", "popular opinion" and "large [unspecified] numbers of people" but I don't think he's going to be the one honoring your warranty if you prematurely destroy your engine.
So he's done some barnstorming with 300 engines and that's admirable. But KHI's engineers probably went through more engines than that determining the shapes of the internal engine parts, the alloys they're made of and in the wording of the "myth" perpetuated in our owner's manual.
Most of us (and probably also KHI's engineers) were already aware that the pressure above the rings is what is forcing them down, out and sealing them against the cylinder wall. He points out the obvious as if it were a technological breakthrough that KHI's engineers weren't already aware of.
And I love how he begins the paragraph with "Nowadays, the piston ring seal is really what the break in process is all about." BWAHAHAHA! Errm, the piston ring seal has ~always~ been 'what it's all about'.
I've heard reports of people claiming to gain a fraction of a horsepower by 'running it hard', but none of these people bought two bikes to conduct proper experimentation to qualify this statement. Anyway, to me an engine that lasts more than 50,000 miles without burning oil is infinitely preferable to one that has an extra fraction of an hp during its first 20,000 miles.
People are going to break-in their engines however they like, but Motoman's method will never be employed by me. And the more widespread his technique becomes, the less likely I am to ever buy a used bike from some other poor sap who ruined his engine with it.
Peace!
-CCinC
He says plenty about "myths", "popular opinion" and "large [unspecified] numbers of people" but I don't think he's going to be the one honoring your warranty if you prematurely destroy your engine.
So he's done some barnstorming with 300 engines and that's admirable. But KHI's engineers probably went through more engines than that determining the shapes of the internal engine parts, the alloys they're made of and in the wording of the "myth" perpetuated in our owner's manual.
Most of us (and probably also KHI's engineers) were already aware that the pressure above the rings is what is forcing them down, out and sealing them against the cylinder wall. He points out the obvious as if it were a technological breakthrough that KHI's engineers weren't already aware of.
And I love how he begins the paragraph with "Nowadays, the piston ring seal is really what the break in process is all about." BWAHAHAHA! Errm, the piston ring seal has ~always~ been 'what it's all about'.
I've heard reports of people claiming to gain a fraction of a horsepower by 'running it hard', but none of these people bought two bikes to conduct proper experimentation to qualify this statement. Anyway, to me an engine that lasts more than 50,000 miles without burning oil is infinitely preferable to one that has an extra fraction of an hp during its first 20,000 miles.
People are going to break-in their engines however they like, but Motoman's method will never be employed by me. And the more widespread his technique becomes, the less likely I am to ever buy a used bike from some other poor sap who ruined his engine with it.
Peace!
-CCinC
#8
![Default](https://www.kawasakiforums.com/forum/images/icons/icon1.gif)
If you're talking about me, this will hopefully dispel yourmental image:
![](http://www.calamarichris.com/images/040806-chrisneoglala.jpg)
![](http://www.calamarichris.com/images/040817-chriscahitc2.jpg)
(The one on the left was in Ogallala, Nebraska on my way to Philadelphia. And yes, I'd parked the bike for the night by then mother.
)
Burt Monro was more of a live-&-let-live kinda guy; I can't seem to remain quiet when I see people doing things they'll regret later.
You may judge which is preferable in this case.
Peace!
-CCinC
![](http://www.calamarichris.com/images/040806-chrisneoglala.jpg)
![](http://www.calamarichris.com/images/040817-chriscahitc2.jpg)
(The one on the left was in Ogallala, Nebraska on my way to Philadelphia. And yes, I'd parked the bike for the night by then mother.
![Wink](https://www.kawasakiforums.com/forum/images/smilies/wink.gif)
Burt Monro was more of a live-&-let-live kinda guy; I can't seem to remain quiet when I see people doing things they'll regret later.
You may judge which is preferable in this case.
Peace!
-CCinC
#9
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Chris, no offense intended. in fact, I couldn't agree more with your philosophy. I tend to offer suggestions based on my experiences, at least when people ask. However, i've also learned that "my head" may not be (usually isn't) where others heads are (good or bad) and they will make decisions andtake actionbased on their fund of knowledge at the time. (Even if it is in direct conflict with what logic should indicate.)
Have you seen the movie "Next?" In a primitive kind of way, I think most people do this scenario analysis. It seems like they often will miss, deny,or intentionally omit key components in order to justify taking action toward an outcome. Sometimes we take action because we "don't know." Other times we take action because we just want theresult we want, and miss/deny/omit irreversable moments in the process.
A lot of riders don't think about what happens when they do certain things with their bikes, even letting it idle on full choke during the winter. What happens to the oil? What happens to the plugs? Pistons? Where does that moisture go, and when? Nahhhh; don't have time for that mental exercise!! They just wanna turn the key, have it start (every time!) and ride the he77 out of it. Oh yeah, they add gas when a light on the dash tells them to.......
Hopefully, this forum will get riders to THINK about things. Or at least provide them with information they can deny later when their bike turns to crap. Thanks for being a poster who contributes food for thought.
Have you seen the movie "Next?" In a primitive kind of way, I think most people do this scenario analysis. It seems like they often will miss, deny,or intentionally omit key components in order to justify taking action toward an outcome. Sometimes we take action because we "don't know." Other times we take action because we just want theresult we want, and miss/deny/omit irreversable moments in the process.
A lot of riders don't think about what happens when they do certain things with their bikes, even letting it idle on full choke during the winter. What happens to the oil? What happens to the plugs? Pistons? Where does that moisture go, and when? Nahhhh; don't have time for that mental exercise!! They just wanna turn the key, have it start (every time!) and ride the he77 out of it. Oh yeah, they add gas when a light on the dash tells them to.......
Hopefully, this forum will get riders to THINK about things. Or at least provide them with information they can deny later when their bike turns to crap. Thanks for being a poster who contributes food for thought.
![Wink](https://www.kawasakiforums.com/forum/images/smilies/wink.gif)
#10
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Offense? Sorry if I gave the impression that offense had been taken, my 9R brother.
Judging from the film, Munro sounds a lot like the guys I admire: Kevin Cameron, Maynard Hershon and Gordon Jennings. They're usually the bearded, grouch types who take what they need from established wisdom, then branch out on their own and actually experiment.
![](http://www.indianmotorbikes.com/features/munro/Burt%20Munro%20at%20home%201970.jpg)
Two things about humans, IMO, have made us a successful organism:
~We look for patterns
~We subscribe to a culture (or put another way, we do what has worked for others.)
Sadly, myths creep into and eventually saturate our culture about bike modifications and about 'running it hard'. Some people will do these things, then to overcome any ambivalence (or possible embarrassment over wasting money or causing latent damage to their engine) will convince themselves that they have horsepower gains. Since shops with dynos make money by selling aftermarket exhaust pipes (or by rebuilding engines that have latent damage after having been broken-in improperly), they are only too happy to help these myths along.
If everyone who runs-it-hard claims that they are getting more horsepower from their engines than the people who do not, a new wrinkle is introduced to our culture. Sure, Cameron, Hershon, Jennings and Munro were experimenters and tinkerers, but most of the riders I see who get aftermarket pipes don't really experiment. Heck, most of them simply pay the shop to do their oil changes for them!
My first bike was an 883 Sportster and all of the larger 1300+cc Big-Twin Harley riders would tell me I needed "Get after market pipes on that thing to let it breathe!" The funny thing was, my little stock 883 regularly walked away these highly-modified Big-Twins at stoplights. I later learned it was because they were machining and polishing their intake ports, convincing themselves that it was giving them more horsepower. All of them were doing it, and all of them were convinced that their bikes were making more power as a result. Unfortunately for them, an engine RELIES on some intake turbulence to ensure last-minute atomization of the fuel on its way into the chamber. So my little 883 'Bitchbike' was beating them like rented mules.
They accused me of boring it up to 1200cc, of hiding a nitrous bottle, having a 'sleeper', but my secret was having a bone-stock bike.![Smile](https://www.kawasakiforums.com/forum/images/smilies/smile.gif)
I'll look around for Next; thanks for the tip.
Peace!
-CCinC
Judging from the film, Munro sounds a lot like the guys I admire: Kevin Cameron, Maynard Hershon and Gordon Jennings. They're usually the bearded, grouch types who take what they need from established wisdom, then branch out on their own and actually experiment.
![](http://www.indianmotorbikes.com/features/munro/Burt%20Munro%20at%20home%201970.jpg)
Two things about humans, IMO, have made us a successful organism:
~We look for patterns
~We subscribe to a culture (or put another way, we do what has worked for others.)
Sadly, myths creep into and eventually saturate our culture about bike modifications and about 'running it hard'. Some people will do these things, then to overcome any ambivalence (or possible embarrassment over wasting money or causing latent damage to their engine) will convince themselves that they have horsepower gains. Since shops with dynos make money by selling aftermarket exhaust pipes (or by rebuilding engines that have latent damage after having been broken-in improperly), they are only too happy to help these myths along.
If everyone who runs-it-hard claims that they are getting more horsepower from their engines than the people who do not, a new wrinkle is introduced to our culture. Sure, Cameron, Hershon, Jennings and Munro were experimenters and tinkerers, but most of the riders I see who get aftermarket pipes don't really experiment. Heck, most of them simply pay the shop to do their oil changes for them!
My first bike was an 883 Sportster and all of the larger 1300+cc Big-Twin Harley riders would tell me I needed "Get after market pipes on that thing to let it breathe!" The funny thing was, my little stock 883 regularly walked away these highly-modified Big-Twins at stoplights. I later learned it was because they were machining and polishing their intake ports, convincing themselves that it was giving them more horsepower. All of them were doing it, and all of them were convinced that their bikes were making more power as a result. Unfortunately for them, an engine RELIES on some intake turbulence to ensure last-minute atomization of the fuel on its way into the chamber. So my little 883 'Bitchbike' was beating them like rented mules.
They accused me of boring it up to 1200cc, of hiding a nitrous bottle, having a 'sleeper', but my secret was having a bone-stock bike.
![Smile](https://www.kawasakiforums.com/forum/images/smilies/smile.gif)
I'll look around for Next; thanks for the tip.
Peace!
-CCinC