break in
Stellar HDF Member
Joined: Sep 2007
Posts: 2,453
Likes: 667
From: Vancouver Island B.C.
http://joegibbsdriven.com/products/breakin/index.html
http://www.amsoil.com/storefront/brk.aspx
http://royalpurple.com/breakin-oil.html
Lots of break in oil. Usually the downside to synthetics is cost to dump so quick. It is all about seating the rings. The clean piston was from one that was assembled and used as a "training" bike for 3300 miles on the dyno. The one that is "improper break in" shows how the top ring has not sealed, resulting in lower compression and power. You have a short time to seat the rings and that takes cylinder pressure.
Road Master
Joined: Jun 2010
Posts: 1,221
Likes: 4
From: Annemasse (border of Geneva-Switzerland) facing Mt-Blanc.
You want to 'form' your piston rings as well as possible, and this is done by the wear of the new rings while they polish off the machined surface of the inner cylinder walls. The rest of the engine (cams, bearing races, etc...) must remain new.
In the 70's (on this side of the pond) it was common practice in racing shops to hand polish each cylinder with it's piston and rings. It was done by hand, on a bench, with diamond powder and light engine oil (sometimes canola oil) after honing the cylinder on a drill press. Then a good rinse with kerosene and we were ready to go.
The better machining surfaces we have today don't allow the 'individual feel' of a better break in method and I suspect we can only play with the wear of the rings, so I rode my new EG the way I expect to ride it after the first oil change, but only taking heat from the cylinders into account. Now it's perfect.
In the 70's (on this side of the pond) it was common practice in racing shops to hand polish each cylinder with it's piston and rings. It was done by hand, on a bench, with diamond powder and light engine oil (sometimes canola oil) after honing the cylinder on a drill press. Then a good rinse with kerosene and we were ready to go.
The better machining surfaces we have today don't allow the 'individual feel' of a better break in method and I suspect we can only play with the wear of the rings, so I rode my new EG the way I expect to ride it after the first oil change, but only taking heat from the cylinders into account. Now it's perfect.
Intermediate
Joined: Oct 2011
Posts: 39
Likes: 0
From: Colorado Springs
I took it easy for the first 100 miles to make sure nothing was leaking and everything was attached properly. Then gradually increased how I was going to ride it. When I got up to 300 miles I rode it like I stole it, and been riding the chit out ever since. Have 6000 with ZERO issues.
Road Warrior
Joined: Mar 2007
Posts: 1,377
Likes: 8
From: Atlanta, GA
My last motor was a 95'' It had 8000 miles and the crank spun. When I broke it in ,I did it the Motomans way and when I tore it down it was clean, pistons and rings where checked and they were in awsome, damn near new . Motor ran very strong.
Now it's a 103 and I broke it in the same way. 500 miles and again, very strong tight motor.
Now it's a 103 and I broke it in the same way. 500 miles and again, very strong tight motor.
http://www.mototuneusa.com/break_in_secrets.htm
Seasoned HDF Member
Joined: Mar 2010
Posts: 38,456
Likes: 6,377
From: Honah Lee
Motoman is correct in the the rings seal with the high pressure gas from the expanding combustion of the gas and air mixture burning. I have rebuild quite a few engines and you can see this when you machine a cylinder. With the piston at the top the first ring starts about 3/16" . On a worn engine from here down about 1" in the cylinder there will be a area that will be about .005 bigger than the rest of the cylinder from wear. The top ring actually travels another couple inches but the wear will be nominal since the pressure must actually start dropping after an inch or so travel.
What Motoman is missing however is the fact that this pressure that seats the rings and the movement that causes this wear to seat in changes little whether you are turning 2000 or 5000. Granted if you buzz it up to 5000 ever gear shift it will indeed break in faster. However if you drive like that all the time it's just going to wear out faster simple because the engine did a whole lot more revolutions for the amount of miles you have gone if say you never turn much over 2800 rpm and got into the higher gears sooner.
Another interesting fact is that the way the rings seal causes the groove in the piston to get wider. Once the groove gets too wide you loose this seal. The wear in the cylinder and on the piston OD will still not really look all that bad. Of course the piston is trash because the groove is too wide and the cylinder needs bored since the 1" long wear area would leave the cylinder out of round belled out in this area if you tried to rehone it for your crosshatch.
This is why I believe it make little difference in how you break it in. However it is just my opinion.
What Motoman is missing however is the fact that this pressure that seats the rings and the movement that causes this wear to seat in changes little whether you are turning 2000 or 5000. Granted if you buzz it up to 5000 ever gear shift it will indeed break in faster. However if you drive like that all the time it's just going to wear out faster simple because the engine did a whole lot more revolutions for the amount of miles you have gone if say you never turn much over 2800 rpm and got into the higher gears sooner.
Another interesting fact is that the way the rings seal causes the groove in the piston to get wider. Once the groove gets too wide you loose this seal. The wear in the cylinder and on the piston OD will still not really look all that bad. Of course the piston is trash because the groove is too wide and the cylinder needs bored since the 1" long wear area would leave the cylinder out of round belled out in this area if you tried to rehone it for your crosshatch.
This is why I believe it make little difference in how you break it in. However it is just my opinion.
Last edited by Jackie Paper; Dec 1, 2011 at 10:47 AM.
Road Captain
Joined: Oct 2011
Posts: 554
Likes: 5
From: San Diego, Ca.
I rode kind of easy for the first 150-200 miles, varying the speed/rpms-speeding up/slowing down with the gears, cranked it a little harder after that, but never anywhere near full throttle. I hit 500 miles 2 days ago, and changed the oil, HD black filter and HD 20w50 "dino" oil. Still haven't gone wide open yet, but plan on doing it soon. HD said to change oil at 1000 miles, but I didn't like the idea of metal in my oil for another 500 miles. I'm going to do another change at 1000 miles, along with all other 1000 mile service items. By the way, when I put the pipes on, I found the rear brake linkage (the rod at the rear brake cylinder) attaching bolt was ready to fall out! I'm not sure what part of the manufacturing/delivery process this bolt is supposed to be tightened, but if it fell out the result could have been disastrous!
Last edited by A Seabee; Dec 1, 2011 at 11:12 AM.
Outstanding HDF Member
Joined: Nov 2008
Posts: 2,246
Likes: 19
From: Cypress, TX
Warm it up. Ride it like you stole it varying the RPM consistently in all gears. I run it to redline. Don't lug it and don't overheat the motor in the process. Don't use cruise or hold the throttle steady. I use cruise after 500 miles but this is the first bike I've had with cruise. Dump the oil after a couple of hundred miles. Dump again around 500. Change to synthetic at 1000 miles. I've always done my race bikes that way (but I was rebuilding them often not because of wear its just what you do) and I've got 35K on my SG and its still quick (for a tank) and doesn't use a drop of oil.
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Elite HDF Member
Joined: Nov 2010
Posts: 3,846
Likes: 173
From: Simi Valley, CA
not an expert but
http://joegibbsdriven.com/products/breakin/index.html
http://www.amsoil.com/storefront/brk.aspx
http://royalpurple.com/breakin-oil.html
Lots of break in oil. Usually the downside to synthetics is cost to dump so quick. It is all about seating the rings. The clean piston was from one that was assembled and used as a "training" bike for 3300 miles on the dyno. The one that is "improper break in" shows how the top ring has not sealed, resulting in lower compression and power. You have a short time to seat the rings and that takes cylinder pressure.
http://joegibbsdriven.com/products/breakin/index.html
http://www.amsoil.com/storefront/brk.aspx
http://royalpurple.com/breakin-oil.html
Lots of break in oil. Usually the downside to synthetics is cost to dump so quick. It is all about seating the rings. The clean piston was from one that was assembled and used as a "training" bike for 3300 miles on the dyno. The one that is "improper break in" shows how the top ring has not sealed, resulting in lower compression and power. You have a short time to seat the rings and that takes cylinder pressure.
You want to 'form' your piston rings as well as possible, and this is done by the wear of the new rings while they polish off the machined surface of the inner cylinder walls. The rest of the engine (cams, bearing races, etc...) must remain new.
In the 70's (on this side of the pond) it was common practice in racing shops to hand polish each cylinder with it's piston and rings. It was done by hand, on a bench, with diamond powder and light engine oil (sometimes canola oil) after honing the cylinder on a drill press. Then a good rinse with kerosene and we were ready to go.
The better machining surfaces we have today don't allow the 'individual feel' of a better break in method and I suspect we can only play with the wear of the rings, so I rode my new EG the way I expect to ride it after the first oil change, but only taking heat from the cylinders into account. Now it's perfect.
In the 70's (on this side of the pond) it was common practice in racing shops to hand polish each cylinder with it's piston and rings. It was done by hand, on a bench, with diamond powder and light engine oil (sometimes canola oil) after honing the cylinder on a drill press. Then a good rinse with kerosene and we were ready to go.
The better machining surfaces we have today don't allow the 'individual feel' of a better break in method and I suspect we can only play with the wear of the rings, so I rode my new EG the way I expect to ride it after the first oil change, but only taking heat from the cylinders into account. Now it's perfect.
After reading the information provided I'm still not sure this isn't just some marketing scheme. On one hand they all say you want a "controlled" wear for seating the rings, but you still need maximum protection from wear for the other rotating assemblies, specifically the cams and lifters. These two characteristics seem mutually exclusive to me. How does the same oil provide for controlled wear of one surface while completely preventing wear of another surface? One of the links actually said the additive package contained no friction modifiers and then later stated high levels of zinc and phosphorus. Aren't zinc and phosphorus anti-wear friction modifiers?
I'll never have the resources or time to test all of these oils myself so I'll have to form my opinions based on the research of others. When analyzing the claims presented by those doing the research, there are some claims that make perfect sense and others that seem questionable. Like anything else, you can't simply accept what others say with blinders on, you have to access the information and form your own opinions.
At this point in time, my opinion is that any high quality motor oil is more than likely adequate for engine break-in, just like any high quality oil is adequate for everday usage. Are there differences between oils evident in laboratory tests? Absolutely! But in the real world those differences become harder to detect.
Road Master
Joined: Sep 2006
Posts: 1,062
Likes: 4
From: Arizona
This is how I did it when it was brand new.
http://www.mototuneusa.com/break_in_secrets.htm
Steve at GMR broke it in on the dyno when the 107" was built.
Bike ran great both ways.
http://www.mototuneusa.com/break_in_secrets.htm
Steve at GMR broke it in on the dyno when the 107" was built.
Bike ran great both ways.