engine building and break in.... Myths?
08-24-2014, 08:29 AM
#1
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SuperSport
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Location: Thousand Oaks, CA
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engine building and break in.... Myths?
so i built up my "street" VTR engine a while bike with STD bore JE pistons. now i am doing the same with my "track" VTR engine and 2 things have come to light that i wanna run past you fine folk.
the 2 problems i have uncovered
1. Honing Cylinders is POINTLESS and actually HARMS your engine; the only exception being on damaged/rebore to OverSize cylinders.
Article to support this :
Careful with That Hone, Eugene!
2. "Easy" break-in on the new rings is bad and results in burning of oil and loss of power leading to overall damage. For example "taking it easy" for the first 600 miles, as per the manufacturers recommended break in procedure results in improper ring seal leading to problems and poor performance. the theory is that to properly seal new rings, which do not rely on spring tension to seal as they have minimal spring tension, but rather the gases getting underneath the rings and forcing them out against the wall helping them to seal properly. the only way to achieve this is through running the engine hard on acceleration and deceleration, loading the engine both ways. during decel, the vaccum created sucks out any particles rather than them getting get between your rings and piston and eventually causing damage to the cylinder wall.
Article to support this:
Break In Secrets--How To Break In New Motorcycle and Car Engines For More Power
Now neither of these articles are where i learned of these so called automotive "myths". Rather i learned of them on a recent trip to the Monterrey Rolex Historic's AKA Vintage car racing. I am close with a few of the drivers and there mechanics which build and rebuild these motors all the time. so this is coming from knowledgeable people who do this professionally. Now the premise of these practices being refuted is that engine's are made to a much better quality, with much finer tolerances, and higher quality parts than motors of decades past and these "ancient ways" are not only unnecessary, but down right bad.
ahhh but again you say if these old techniques dont apply to new engines, wouldnt the teams racing vintage cars, still abide by the laws of the past? NO because even though the car is old, the motor is new. i recant what i said, most of the cars really arnt even the cars they are suppose to be. they usually are the body of the car, and by that i mean a fibreglass replica with flared wheel wells and all, but underneath is usually a tube chassis with purpose built race engines. usually the tail lights are about the only thing these cars share with the car they are replicating.
so my "street" engine build, i did the traditional "easy" break in, as well as a simple hone on the cylinders. but on my "track" engine, i will do just the opposite. NO hone at all, and a hard break in. i will then compare results via 1.leakdown test 2.compression test 3.Dyno runs to measure power and torque.
now i have before and after dyno runs (thanks to my mates over at ducati) of the "street" engine pre and post piston install with NO other changes.
i will do the same with the "track" engine, the only difference being no hone, and a hard break in. then i will compare the % of either increase(hopefully) or loss of power due to the changes in the build and break in procedure. the compression and leakdown should tell alot of the story as well.
should be interesting, but ive come to find out that my ducati dealer uses the "hard" break in procedure and all freshly out of the crate bikes INCLUDING the $70,000 1199 Superleggera AND in their shop, purely on Re-Ring jobs that have no damage to cylinder walls, they DO NOT hone the cylinder. they simply check for tolerance specs, and if all is well, re-ring and button it up. a number of the bikes that come through the shop have been upgraded with low friction 2 ring pistons which require changing more often. so this info is consistent with what i learned in Monterrey. hence why i am trying it all out.
i know some of you will call me stupid, and that i will destroy my engine, but i wanna know for myself what the truth is in these matters and its a risk i am willing to take. from the research ive done, and the people ive talked to, id be stupid to hone the bores, as well as loosing on power if i run the engine in easy. so we shall see! would love to know what you guys make of all this!
the 2 problems i have uncovered
1. Honing Cylinders is POINTLESS and actually HARMS your engine; the only exception being on damaged/rebore to OverSize cylinders.
Article to support this :
Careful with That Hone, Eugene!
2. "Easy" break-in on the new rings is bad and results in burning of oil and loss of power leading to overall damage. For example "taking it easy" for the first 600 miles, as per the manufacturers recommended break in procedure results in improper ring seal leading to problems and poor performance. the theory is that to properly seal new rings, which do not rely on spring tension to seal as they have minimal spring tension, but rather the gases getting underneath the rings and forcing them out against the wall helping them to seal properly. the only way to achieve this is through running the engine hard on acceleration and deceleration, loading the engine both ways. during decel, the vaccum created sucks out any particles rather than them getting get between your rings and piston and eventually causing damage to the cylinder wall.
Article to support this:
Break In Secrets--How To Break In New Motorcycle and Car Engines For More Power
Now neither of these articles are where i learned of these so called automotive "myths". Rather i learned of them on a recent trip to the Monterrey Rolex Historic's AKA Vintage car racing. I am close with a few of the drivers and there mechanics which build and rebuild these motors all the time. so this is coming from knowledgeable people who do this professionally. Now the premise of these practices being refuted is that engine's are made to a much better quality, with much finer tolerances, and higher quality parts than motors of decades past and these "ancient ways" are not only unnecessary, but down right bad.
ahhh but again you say if these old techniques dont apply to new engines, wouldnt the teams racing vintage cars, still abide by the laws of the past? NO because even though the car is old, the motor is new. i recant what i said, most of the cars really arnt even the cars they are suppose to be. they usually are the body of the car, and by that i mean a fibreglass replica with flared wheel wells and all, but underneath is usually a tube chassis with purpose built race engines. usually the tail lights are about the only thing these cars share with the car they are replicating.
so my "street" engine build, i did the traditional "easy" break in, as well as a simple hone on the cylinders. but on my "track" engine, i will do just the opposite. NO hone at all, and a hard break in. i will then compare results via 1.leakdown test 2.compression test 3.Dyno runs to measure power and torque.
now i have before and after dyno runs (thanks to my mates over at ducati) of the "street" engine pre and post piston install with NO other changes.
i will do the same with the "track" engine, the only difference being no hone, and a hard break in. then i will compare the % of either increase(hopefully) or loss of power due to the changes in the build and break in procedure. the compression and leakdown should tell alot of the story as well.
should be interesting, but ive come to find out that my ducati dealer uses the "hard" break in procedure and all freshly out of the crate bikes INCLUDING the $70,000 1199 Superleggera AND in their shop, purely on Re-Ring jobs that have no damage to cylinder walls, they DO NOT hone the cylinder. they simply check for tolerance specs, and if all is well, re-ring and button it up. a number of the bikes that come through the shop have been upgraded with low friction 2 ring pistons which require changing more often. so this info is consistent with what i learned in Monterrey. hence why i am trying it all out.
i know some of you will call me stupid, and that i will destroy my engine, but i wanna know for myself what the truth is in these matters and its a risk i am willing to take. from the research ive done, and the people ive talked to, id be stupid to hone the bores, as well as loosing on power if i run the engine in easy. so we shall see! would love to know what you guys make of all this!
08-24-2014, 09:38 AM
#2
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SuperBike
Join Date: Apr 2013
Location: Geneseo, IL
Posts: 2,017
Regarding break-in, it's always been my understanding that the engine needs to be loaded just as you outline for best ring seal. Also, you should vary RPM during break-in rather than holding a sustained constant RPM such as an extended freeway distance. I'm no mechanic, just a guy on the internet.
08-24-2014, 02:07 PM
#4
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SuperBike
Join Date: Mar 2012
Location: New South Wales Australia
Posts: 1,544
With a new car or bike I have always thrashed them .
Nothing ridiculous, just work them hard.
Never had a problem.
Usually give it a real hard hit at about 500K's.
Same goes for rebuilt engines.
I have never followed manufacturers instructions.
I believe that engines have a "Memory" kinda like an athlete and muscle memory.
You can always feel it when you drive or ride someone else's car or bike over an extended time and I believe that this is due to the way the engine has been run in.
We've all had a mate who thrashed his new bike from day one and expected for them to have major problems but their bike just kept going like stink.
No running in for me, just vary the engine loads and don't redline it for about 500 K's!
Just my two bobs worth!
Nothing ridiculous, just work them hard.
Never had a problem.
Usually give it a real hard hit at about 500K's.
Same goes for rebuilt engines.
I have never followed manufacturers instructions.
I believe that engines have a "Memory" kinda like an athlete and muscle memory.
You can always feel it when you drive or ride someone else's car or bike over an extended time and I believe that this is due to the way the engine has been run in.
We've all had a mate who thrashed his new bike from day one and expected for them to have major problems but their bike just kept going like stink.
No running in for me, just vary the engine loads and don't redline it for about 500 K's!
Just my two bobs worth!
08-24-2014, 03:42 PM
#5
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Superstock
Join Date: Jul 2013
Location: Rome, GA
Posts: 458
The important thing is to be smooth when breaking in an engine and not to snap the throttle open or closed quickly. Reason being is to not damage the bearings of the engine since on a "new" engine (IE not rebuilt to the same bore, but an actual new engine or one that has been bored out) the bore is a little tighter and jerking the throttle is hard on the bearings and rods (though generally the rods can take the punishment)
08-24-2014, 09:21 PM
#6
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MotoGP
Join Date: Jul 2007
Location: NYC
Posts: 5,033
This is interesting stuff. My only experience with breaking/running in newly bored cylinders and new pistons is on the track. To me its so hard to tell how fast or hard your going on the track but I can say its WAY faster than the street.
I think if I ran it on the street like I broke it in on the track I would look like a nut. I know for sure you cant use synthetic oil for the break in, I accidently tried that once.
So the big question is, if this method rules, whats with every OEM saying dont do it? Why would they care? Also, isnt high throttle at low rpm way more load than higher rpm? Just another thing I heard.
I think if I ran it on the street like I broke it in on the track I would look like a nut. I know for sure you cant use synthetic oil for the break in, I accidently tried that once.
So the big question is, if this method rules, whats with every OEM saying dont do it? Why would they care? Also, isnt high throttle at low rpm way more load than higher rpm? Just another thing I heard.
08-24-2014, 09:41 PM
#7
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SuperSport
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Location: Thousand Oaks, CA
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so from what i understand ( and i could be completley wrong) but the lad on the engine is dependant on the RPM, gear, and speed. for example more load is placed on the engine when you first crack the throttle as its working hard to propel you forward from a slower momentum compared to a constant cruising at a high RPM where the engine is really just keeping you at a constant speed. is important to load the engine on decel as well so basically you want to use a mixture of hard opening and closing of the throttle in various gears at various RPMs.
in regards to the manufacturers.... it baffles me too. they designed the damn engine so shouldnt they know whats best for it?
my bet is that they arnt gonna tell people to go take there bikes up to 10,000 rpm on the streets due to the MAJOR liability and lawsuits that would follow from idiots recking the bike and themselves claiming that they were just following the manufactures orders.
08-25-2014, 02:42 AM
#8
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SuperBike
Join Date: Mar 2012
Location: New South Wales Australia
Posts: 1,544
I have been in the automotive industry for 40 years and have visited many car plants around the globe.
I always have a silent chuckle when someone picks up a new car and asks about the running in procedure.
If they saw what was done to their engine in the test bed they would **** themselves.
The new engines get an absolute thrashing and then the factory tells you to take it easy.
It's a joke really!!
All things considered the engines are not connected to the drive line so the loads are much less than when installed in the vehicle, but they do flog them and I have come to the conclusion that it is to bed the rings in as most people drive their new cars like pussies and would glaze the bores up so the factory beds the rings for them and saves on warranty costs.
I always have a silent chuckle when someone picks up a new car and asks about the running in procedure.
If they saw what was done to their engine in the test bed they would **** themselves.
The new engines get an absolute thrashing and then the factory tells you to take it easy.
It's a joke really!!
All things considered the engines are not connected to the drive line so the loads are much less than when installed in the vehicle, but they do flog them and I have come to the conclusion that it is to bed the rings in as most people drive their new cars like pussies and would glaze the bores up so the factory beds the rings for them and saves on warranty costs.
09-30-2014, 02:03 AM
#9
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Squid
Join Date: Aug 2013
Posts: 35
Yup!+1 on the manufacturers run test and tweak tune before the engine is installed. There would be a steady line at the restroom doors to change their laundry were they to see what the engines are subjected to. I don't know if it is an industry wide practice, but the largest motorcycle dealer here in our area has the guys breaking the brand new bikes out of the shipping crates and assembling them, 1. Check all fliud levels, 2. Fire the bike and allow them to warmup, 3. Twist them until they bounce off the rev limiter 2or3 times. Then take them out in the side lot and make 3 or 4 hard passes the length of the lot. Then they go to the wash bay to get the fluff & buff before going to the showroom. I thought that would be an interesting job, you get to brutalise some other unsuspecting individual brand new pride and joy and be paid to do it.
The Dragons Tail runs through my backyard
The Dragons Tail runs through my backyard
10-01-2014, 10:06 PM
#10
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10-04-2014, 11:27 PM
#14
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Honing, it's a good thing!
Honing a cylinder cleans up the carbon build up at the top and the bottom of the cylinder which needs to be removed for a proper top end job!
Run your finger on the smooth cylinder wall towards the top of the cylinder and you will feel the carbon, be careful because the top of the cylinder has sharp edges that will cut your fingers.
A proper hone will remove the glaze on the cylinder wall which may have worn the cylinder to an oval from a circle.
A good mechanic can use the honing bar to expand the ID of the cylinder wall to fit the next size of rings using the OEM piston which is the least expensive way to service the pistons.
When I do a honing job on one of my bikes I always replace the top end rod bearings.
Lots of guys use a deglazing tool and OEM stock rings thinking this is a hone but it's not.
A hone measures ID of the cylinder wall against the OD of the piston, this measurement determines how much of the cylinder needs to be removed in order to fit the next in a series of rings for the VTR.
I think you can go 3 over before a larger piston and bore job is needed using the OEM pistons.
AS far as breaking in a bike with a fresh top end I fire up the bike and wait for the oil pressure to build up as I look for leaks, if everything looks good I usually stand on her until the cooling fan turns on and then I do a slow cool down again looking for leaks and listening for any chirps or whistles from the motor which indicates air leaks.
That is how I have been doing top end jobs for the past 40 years and I have yet to toast one! I have been lucky over the years having complete access to the service area and master Honda mechanics at the local shop which has taught a lot over the years!
The shops master Honda mechanic would never turn a wrench on any of my bikes but he would explain how it needs to be done and I would go to work. If I was bored in the evening I would go up to the shop and watch them work on race bikes, my job was to grind and polish rods which taught me how to polish aluminum which I have gotten pretty good at but it is a real messy and dirty job.
Sorry for rambling!
SIRR1
Run your finger on the smooth cylinder wall towards the top of the cylinder and you will feel the carbon, be careful because the top of the cylinder has sharp edges that will cut your fingers.
A proper hone will remove the glaze on the cylinder wall which may have worn the cylinder to an oval from a circle.
A good mechanic can use the honing bar to expand the ID of the cylinder wall to fit the next size of rings using the OEM piston which is the least expensive way to service the pistons.
When I do a honing job on one of my bikes I always replace the top end rod bearings.
Lots of guys use a deglazing tool and OEM stock rings thinking this is a hone but it's not.
A hone measures ID of the cylinder wall against the OD of the piston, this measurement determines how much of the cylinder needs to be removed in order to fit the next in a series of rings for the VTR.
I think you can go 3 over before a larger piston and bore job is needed using the OEM pistons.
AS far as breaking in a bike with a fresh top end I fire up the bike and wait for the oil pressure to build up as I look for leaks, if everything looks good I usually stand on her until the cooling fan turns on and then I do a slow cool down again looking for leaks and listening for any chirps or whistles from the motor which indicates air leaks.
That is how I have been doing top end jobs for the past 40 years and I have yet to toast one! I have been lucky over the years having complete access to the service area and master Honda mechanics at the local shop which has taught a lot over the years!
The shops master Honda mechanic would never turn a wrench on any of my bikes but he would explain how it needs to be done and I would go to work. If I was bored in the evening I would go up to the shop and watch them work on race bikes, my job was to grind and polish rods which taught me how to polish aluminum which I have gotten pretty good at but it is a real messy and dirty job.
Sorry for rambling!
SIRR1
02-07-2015, 03:00 PM
#17
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Retired and certified bike mechanic here. (part timer now) Unless it's a chrome bore, I hone. Break the glaze and bed in the rings. There is however a fine line...Hone too vigorously and you increase the bore and even get it out of round. I use "BB" hones. To bed in the pistons. This is especially critical in a piston port two stroke engine as it gently rounds the transfer ports. I always build up the revs at about 50 miles or so. I would recommend a fairly easy 250 miles. The force pushes the rings out and beds them in. I know a lot of very good mechanics and we all have different techniques. Frankly, the largest part of my experience is from older superbikes. (Air cooled) I'm not sure that there IS a correct way to break in an engine. Now, anyone want to talk about the "special" factory "Break in oil"? We got into that on the ZX1441R site. I've assembled seventeen of them, including my own...And just THREE of them came from the factory full of oil. The rest? We put in off the shelf Kawasaki green label dino oil. Go figure.
Last edited by ZERO; 02-07-2015 at 03:03 PM.
02-07-2015, 04:41 PM
#18
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Join Date: Dec 2014
Location: Dallas, TX
Posts: 283
This has been of interest to me since I am doing a rebuild. Back in my shop days (and bear in mind this was for pre-1980 motorcycles, my boss insisted that rings go in dry bores. The wings were washed as were the bores in hot soapy water and left to dry. He wanted a nice coating of rust all over the bore as an assurance that it was oil free.
On start the engine was kicked through until oil showed at the open oil presser sending unit port. After that an oil pressure gauge was attached to that port and the bike was started. Once the oil pressure reached it's indicated level my boss would crank the throttle open and hold it there. He did not red line it but he did run it at 6K out of a possible 7.5. It really made you cringe if you had built up that motor but it worked.
His theory on the rings was that after less than 50 revolutions the piston skirt will be covered in oil. The only things that will happen to the rings and the bore in that time is that they will get very well acquainted.
On start the engine was kicked through until oil showed at the open oil presser sending unit port. After that an oil pressure gauge was attached to that port and the bike was started. Once the oil pressure reached it's indicated level my boss would crank the throttle open and hold it there. He did not red line it but he did run it at 6K out of a possible 7.5. It really made you cringe if you had built up that motor but it worked.
His theory on the rings was that after less than 50 revolutions the piston skirt will be covered in oil. The only things that will happen to the rings and the bore in that time is that they will get very well acquainted.
02-07-2015, 06:47 PM
#19
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This has been of interest to me since I am doing a rebuild. Back in my shop days (and bear in mind this was for pre-1980 motorcycles, my boss insisted that rings go in dry bores. The wings were washed as were the bores in hot soapy water and left to dry. He wanted a nice coating of rust all over the bore as an assurance that it was oil free.
On start the engine was kicked through until oil showed at the open oil presser sending unit port. After that an oil pressure gauge was attached to that port and the bike was started. Once the oil pressure reached it's indicated level my boss would crank the throttle open and hold it there. He did not red line it but he did run it at 6K out of a possible 7.5. It really made you cringe if you had built up that motor but it worked.
His theory on the rings was that after less than 50 revolutions the piston skirt will be covered in oil. The only things that will happen to the rings and the bore in that time is that they will get very well acquainted.
On start the engine was kicked through until oil showed at the open oil presser sending unit port. After that an oil pressure gauge was attached to that port and the bike was started. Once the oil pressure reached it's indicated level my boss would crank the throttle open and hold it there. He did not red line it but he did run it at 6K out of a possible 7.5. It really made you cringe if you had built up that motor but it worked.
His theory on the rings was that after less than 50 revolutions the piston skirt will be covered in oil. The only things that will happen to the rings and the bore in that time is that they will get very well acquainted.
A thumb print of oil on the skirt if you feel you must.. but make sure the bore and rings are clean and dry.
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