New top end break in
- Thread starter IDAHOSPUD
- Start date
swazi_matt
Active member
this is what i have used successfully and there is theory in it that makes sense - cannot remember the source (but honestly i had to find something that saved me from the horror of having to ride two tanks below powerband;-))
1st. Idling a bike for a long time is WRONG!!!!! When any motor, 2 or 4 stroke idles, it generates very low oil pressure. This increases friction inside the motor. On two stroke motors, where you have an auto lube system, when you idle the bike, there is very little airflow, and it creates a poor mix between the oil and the fuel. The oil runs along the bottom on the intake, and into the crank area, and very little gets to the piston and rings, again, causing additional friction. The longer you leave the motor idling, the more those rings and sleeve wear, simply because there is no oil lubricating it. The problem is less on 4 strokes, but a motor idling around 1500 RPM or lower, does not generate the correct oil pressure. Meaning, all the moving parts can be affected. It also takes a longer time for the oil to reach all the right places, especially if it has been standing for a while
Then on top of that, when the motor is cold, the combustion process creates acids that collect inside the motor. These acids eat away slowly at the metal and you know what happens with metal and acids.
Also, a bike that stands still, has no air flowing over the motor, cooling it down, and over time, heat will build up. The cooling system has a fan and all the rest, but the motor was not designed to idle like this, it is there to be ridden, and the air flowing over the motor actually does a big part in helping it to stay cool. The cooling system and water only cools around the sleeve, and the head, and the rest of the motor relies on air cooling.
Also, extensive carbon is being built up during the idling process, because the fuel is not burned correctly. The carbon collects inside the combustion chamber, on top of the piston and inside the exhaust. This will affect performance over time.
Then, at idle, unburned fuel can collect on the side of the sleeve, where it dilutes the oil used to lubricate the parts. Also, ring seal is poor during idle, and fuel and combustion gasses gets past the rings, and ends up inside the oil, where it starts breaking it down, and reducing the oils efficiency to lubricate the parts.
So, if you really want to mess up a good motor, go ahead, idle that sucker. I get really upset about the misinformation people feed clients, and they don?t think what the impact is of what they tell people.
So, what do you do?
You cannot ride a cold bike and give it horns.. The correct way is to start the bike, open the throttle lightly, to give the bike a bit of RPM, to get the oil pressure up, and to get the oil circulating around the motor as soon as possible. You can also turn the idle screw, to up the RPM?s to around 2000 to 2500 RPM for about 15 to 20 seconds. Once done, set the idle back to normal and as soon as possible, start riding it. Ride it slowly, and keep the throttle under ?, and if you have a rev counter try not to go over 3500 to 4000 RPM. Take it slow, and don?t give it full throttle. Ride around in the parking area if you must, but ride the thing slowly, and don?t labour the motor.
What this does, is help the motor to warm up much quicker, which limits the acid and the additional carbon build up. Fuel mixture is better, which creates a cleaner burn, and oil pressure is also at optimum, so it lubricates the motor much better. With two stroke motor, you also have a better mix of oil and fuel, so the parts get the right amount of oil they need. Also, your cooling is better, since you have airflow over the motor
You can start your ride like this, and about 5 min later, you can let rip.
Now. 2nd part to running in the motor.
A lot of people say take it easy, and don?t give it full throttle, and all this cool down nocence.
Let me again explain a few things. 1st the cool down. They claim that the cool down period is required to temper the metal rings. Metal gets harder when you temper it, so it sounds like a good plan. Well, the real facts are that you cannot temper metal inside a motor. When you get new rings, they are already treated by the manufacturer. Also, to temper metal you need to make that peace of metal red or white hot. Now, by the time you generate that about of heat inside the motor, the aluminium piston and head would have melted a long time ago, and the sleeve and rings would basically start to fuse together.
Now if you want to go by that stupid idea, there is a way to do this, and create the right amount of heat to warm up the metal to such a degree that you can start change it?s strength. To do this, drain all the oil and water out the motor, and go ride the bike like that. Once you get a light heat seize, you just about reached the right temperature to start tempering the metal. Well, I would not advise this practise, but that is actually what you need to do to temper metal, using your bikes motor.
The only time you would need to cool the motor, is when you run in the bike, on a dyno, where there is no additional airflow, like you would have while riding your bike. While you ride, the cooling system and air will take care of the rest. You can also stop for brief moments, to let the motor cool, but a 5 min stop is fine. No need to let it cool down to room temperature. The theory behind a quick stop, is to let the new rings cool down a bit, and to give you a chance to check the oil and water levels, and look for oil leaks. Once or twice is fine for a quick stop.
1st. Idling a bike for a long time is WRONG!!!!! When any motor, 2 or 4 stroke idles, it generates very low oil pressure. This increases friction inside the motor. On two stroke motors, where you have an auto lube system, when you idle the bike, there is very little airflow, and it creates a poor mix between the oil and the fuel. The oil runs along the bottom on the intake, and into the crank area, and very little gets to the piston and rings, again, causing additional friction. The longer you leave the motor idling, the more those rings and sleeve wear, simply because there is no oil lubricating it. The problem is less on 4 strokes, but a motor idling around 1500 RPM or lower, does not generate the correct oil pressure. Meaning, all the moving parts can be affected. It also takes a longer time for the oil to reach all the right places, especially if it has been standing for a while
Then on top of that, when the motor is cold, the combustion process creates acids that collect inside the motor. These acids eat away slowly at the metal and you know what happens with metal and acids.
Also, a bike that stands still, has no air flowing over the motor, cooling it down, and over time, heat will build up. The cooling system has a fan and all the rest, but the motor was not designed to idle like this, it is there to be ridden, and the air flowing over the motor actually does a big part in helping it to stay cool. The cooling system and water only cools around the sleeve, and the head, and the rest of the motor relies on air cooling.
Also, extensive carbon is being built up during the idling process, because the fuel is not burned correctly. The carbon collects inside the combustion chamber, on top of the piston and inside the exhaust. This will affect performance over time.
Then, at idle, unburned fuel can collect on the side of the sleeve, where it dilutes the oil used to lubricate the parts. Also, ring seal is poor during idle, and fuel and combustion gasses gets past the rings, and ends up inside the oil, where it starts breaking it down, and reducing the oils efficiency to lubricate the parts.
So, if you really want to mess up a good motor, go ahead, idle that sucker. I get really upset about the misinformation people feed clients, and they don?t think what the impact is of what they tell people.
So, what do you do?
You cannot ride a cold bike and give it horns.. The correct way is to start the bike, open the throttle lightly, to give the bike a bit of RPM, to get the oil pressure up, and to get the oil circulating around the motor as soon as possible. You can also turn the idle screw, to up the RPM?s to around 2000 to 2500 RPM for about 15 to 20 seconds. Once done, set the idle back to normal and as soon as possible, start riding it. Ride it slowly, and keep the throttle under ?, and if you have a rev counter try not to go over 3500 to 4000 RPM. Take it slow, and don?t give it full throttle. Ride around in the parking area if you must, but ride the thing slowly, and don?t labour the motor.
What this does, is help the motor to warm up much quicker, which limits the acid and the additional carbon build up. Fuel mixture is better, which creates a cleaner burn, and oil pressure is also at optimum, so it lubricates the motor much better. With two stroke motor, you also have a better mix of oil and fuel, so the parts get the right amount of oil they need. Also, your cooling is better, since you have airflow over the motor
You can start your ride like this, and about 5 min later, you can let rip.
Now. 2nd part to running in the motor.
A lot of people say take it easy, and don?t give it full throttle, and all this cool down nocence.
Let me again explain a few things. 1st the cool down. They claim that the cool down period is required to temper the metal rings. Metal gets harder when you temper it, so it sounds like a good plan. Well, the real facts are that you cannot temper metal inside a motor. When you get new rings, they are already treated by the manufacturer. Also, to temper metal you need to make that peace of metal red or white hot. Now, by the time you generate that about of heat inside the motor, the aluminium piston and head would have melted a long time ago, and the sleeve and rings would basically start to fuse together.
Now if you want to go by that stupid idea, there is a way to do this, and create the right amount of heat to warm up the metal to such a degree that you can start change it?s strength. To do this, drain all the oil and water out the motor, and go ride the bike like that. Once you get a light heat seize, you just about reached the right temperature to start tempering the metal. Well, I would not advise this practise, but that is actually what you need to do to temper metal, using your bikes motor.
The only time you would need to cool the motor, is when you run in the bike, on a dyno, where there is no additional airflow, like you would have while riding your bike. While you ride, the cooling system and air will take care of the rest. You can also stop for brief moments, to let the motor cool, but a 5 min stop is fine. No need to let it cool down to room temperature. The theory behind a quick stop, is to let the new rings cool down a bit, and to give you a chance to check the oil and water levels, and look for oil leaks. Once or twice is fine for a quick stop.
swazi_matt
Active member
Ok, now to how to ride the bike in. Well, here again, partial throttle or taking it easy, is in actual fact mad for the rings.
Again, let me explain.
A new sleeve is honed to create a rough surface. This rough surface is there to ?file? the rings into the right shape to match and seal correctly with the sleeve. The hone or rough surface on the sleeve is only really effective during the 1st 500Km?s or even less.
Now to the rings. A ring by itself cannot apply the right pressure to the sleeve to form a good seal. For it to create a good seal, the ring relies on the motor?s compression. The pressure moves in behind the ring, and press the ring against the sleeve,a nd create a good seal. Now it is critical to get the right pressure behind the ring to seal correctly, and for it to be ?filed? to match the sleeve. The only way to do that, is to apply full throttle. Full throttle will allow the motor to reach maximum compression, which in turn applies the right amount of force to ?file? those rings into shape. The hone or roughness in the sleeve is only there for a short while, before the rings smooth them out, and if you don?t apply full throttle, the ring swill never mould correctly to the sleeve.
Think of it this way. You are given a peace of metal, and told you have to file it into a shape, but, the file you are given will only last for a 1000 file movements. If you apply light force, you are never going to get the job done, and it will not be the right shape by the time the file is finished. To do it, you need to apply all the pressure you can, and make use of that files full potential.
Then, as previously explained, the rings are tempered by the time you get them, so they are strong from day one. If they are mounted correctly, then they will not break under full throttle. Rings don?t need time to settle in and get cosy, they either work or they don?t.
Also, if you don?t cycle the RPM between low and max, you also create a problem for the rings. What most people don?t know is that the connecting rod that holds the piston to the crank, actually stretches. The higher the RPM the longer it gets. This means that the top of the piston can actually can go higher up the inside of the sleeve, depending on how much RPM you give it.
Now, if you take it easy for the 1st couple of hundred km?s, the rings wear in, and they clean the sleeve as they go. That?s great. Now, you think your done, and you give it horns again. What now happens is that the red stretches a little, and the rings go to areas in the sleeve where they have not gone before. These new areas are rough. The ring goes from smooth to very rough, and this can deform the rings, or damage them, causing poor ring seal.
So, now to what is the best way to run the bike in.
You warm up the motor as per the method I explained earlier. Drive it easy. Once you get the motor to normal operating temperature, you do the following.
Do 3 to 5 ? RPM runs. Now, to do this, you pick a nice flat quite peace of road. Start in 1st gear, and take of slowly, then select 2nd gear. Once you are in 2nd gear, open to full throttle, but don?t exceed ? the RPM range of the motor. Example. If the red line is at 10 000 RPM, don?t exceed 5000 RPM. Once you reach ? RPM range, change gears like normal followed by full throttle again. Change gears at ? RPM range. Go thru all the gears. Slow down back the 1st gear and do this for 3 to 4 times more.
What is very critical, is that once you slow down, you must not use your breaks. Let the bike slow down under compression. Click down thru the gears t, back to 1st, but keep the RPM down, when you do this. Don?t change down, and let the motor spin up high. This process helps the rings to clear out the metal filings from the sleeve, and is very critical.
Once done, do the same process, but instead of stopping at ? RPM, you change gears at ? RPM range. Remember to do the compression breaking between runs.
Once that is done, you do it again, but this time you do it to max RPM, or just before the limiter. Remember to do the compression breaking between runs.
When that whole thing is done, you can take a break and let the motor cool down and you have time to do your checks to see if there are any leaks.
It is also a good idea to take the bike for a burn around a track, where you have lots of full throttle runs, combined with breaking, and acceleration. A new motor loves that.
After about 1000 Km/s drain the oil, and install new oil filter and new oil.
Now to the last bit. What very few people know, is that a new bike never leave the factory without passing a ?run in?. The factory assembles the motor and then the fun starts. They run it into the red line for a few minutes, and keep it there, before that motor goes into the bike. They do this to ensure that this motor is going to hold up, and not break when you ride for the 1st time. If it breaks the motor goes onto the scrap heap.
For those of you who had the privilege to get a brand new bike in the crate, you will see the carb has fuel in it, and the motor has oil, but there is no fuel in the fuel tank. Again, it is leftovers from the factory break in or test run.
By the time you get your bike, it has been hammered, and trying to take it easy is actually pointless, besides all the other negative stuff I just mentioned about why not to take it easy. I have opened up brand new bike motors from the factory, and the sleeves hone pattern is almost gone. The only way for it to be like that, is from running in that motor at the factory.
Then, further. Speak to the pro race teams. From cars to bikes. Do you think they run their race motors in? No, Nissan race team takes a brand new motor of the assembly line, and the thing goes in and is hammered from day one.
Then, Dakar, they rebuild those motors overnight, and the next day they ride them, full taps. Again no break in. Do you think for one second that if break in is so critical to ensure that a motor will not break, that they will skip that step?
Also, bikes that have been run in the hard way, actually make between 5 to 10% more power in the dynos, compared to the ones that was babied. If the heard break in was bad, why would they make more power, and why are the babied bikes down on power.
Maybe it?s time people know the real truth about how to break in a motor. It takes guts, but warm up the motor correctly, and your set to let it rip.
Again, let me explain.
A new sleeve is honed to create a rough surface. This rough surface is there to ?file? the rings into the right shape to match and seal correctly with the sleeve. The hone or rough surface on the sleeve is only really effective during the 1st 500Km?s or even less.
Now to the rings. A ring by itself cannot apply the right pressure to the sleeve to form a good seal. For it to create a good seal, the ring relies on the motor?s compression. The pressure moves in behind the ring, and press the ring against the sleeve,a nd create a good seal. Now it is critical to get the right pressure behind the ring to seal correctly, and for it to be ?filed? to match the sleeve. The only way to do that, is to apply full throttle. Full throttle will allow the motor to reach maximum compression, which in turn applies the right amount of force to ?file? those rings into shape. The hone or roughness in the sleeve is only there for a short while, before the rings smooth them out, and if you don?t apply full throttle, the ring swill never mould correctly to the sleeve.
Think of it this way. You are given a peace of metal, and told you have to file it into a shape, but, the file you are given will only last for a 1000 file movements. If you apply light force, you are never going to get the job done, and it will not be the right shape by the time the file is finished. To do it, you need to apply all the pressure you can, and make use of that files full potential.
Then, as previously explained, the rings are tempered by the time you get them, so they are strong from day one. If they are mounted correctly, then they will not break under full throttle. Rings don?t need time to settle in and get cosy, they either work or they don?t.
Also, if you don?t cycle the RPM between low and max, you also create a problem for the rings. What most people don?t know is that the connecting rod that holds the piston to the crank, actually stretches. The higher the RPM the longer it gets. This means that the top of the piston can actually can go higher up the inside of the sleeve, depending on how much RPM you give it.
Now, if you take it easy for the 1st couple of hundred km?s, the rings wear in, and they clean the sleeve as they go. That?s great. Now, you think your done, and you give it horns again. What now happens is that the red stretches a little, and the rings go to areas in the sleeve where they have not gone before. These new areas are rough. The ring goes from smooth to very rough, and this can deform the rings, or damage them, causing poor ring seal.
So, now to what is the best way to run the bike in.
You warm up the motor as per the method I explained earlier. Drive it easy. Once you get the motor to normal operating temperature, you do the following.
Do 3 to 5 ? RPM runs. Now, to do this, you pick a nice flat quite peace of road. Start in 1st gear, and take of slowly, then select 2nd gear. Once you are in 2nd gear, open to full throttle, but don?t exceed ? the RPM range of the motor. Example. If the red line is at 10 000 RPM, don?t exceed 5000 RPM. Once you reach ? RPM range, change gears like normal followed by full throttle again. Change gears at ? RPM range. Go thru all the gears. Slow down back the 1st gear and do this for 3 to 4 times more.
What is very critical, is that once you slow down, you must not use your breaks. Let the bike slow down under compression. Click down thru the gears t, back to 1st, but keep the RPM down, when you do this. Don?t change down, and let the motor spin up high. This process helps the rings to clear out the metal filings from the sleeve, and is very critical.
Once done, do the same process, but instead of stopping at ? RPM, you change gears at ? RPM range. Remember to do the compression breaking between runs.
Once that is done, you do it again, but this time you do it to max RPM, or just before the limiter. Remember to do the compression breaking between runs.
When that whole thing is done, you can take a break and let the motor cool down and you have time to do your checks to see if there are any leaks.
It is also a good idea to take the bike for a burn around a track, where you have lots of full throttle runs, combined with breaking, and acceleration. A new motor loves that.
After about 1000 Km/s drain the oil, and install new oil filter and new oil.
Now to the last bit. What very few people know, is that a new bike never leave the factory without passing a ?run in?. The factory assembles the motor and then the fun starts. They run it into the red line for a few minutes, and keep it there, before that motor goes into the bike. They do this to ensure that this motor is going to hold up, and not break when you ride for the 1st time. If it breaks the motor goes onto the scrap heap.
For those of you who had the privilege to get a brand new bike in the crate, you will see the carb has fuel in it, and the motor has oil, but there is no fuel in the fuel tank. Again, it is leftovers from the factory break in or test run.
By the time you get your bike, it has been hammered, and trying to take it easy is actually pointless, besides all the other negative stuff I just mentioned about why not to take it easy. I have opened up brand new bike motors from the factory, and the sleeves hone pattern is almost gone. The only way for it to be like that, is from running in that motor at the factory.
Then, further. Speak to the pro race teams. From cars to bikes. Do you think they run their race motors in? No, Nissan race team takes a brand new motor of the assembly line, and the thing goes in and is hammered from day one.
Then, Dakar, they rebuild those motors overnight, and the next day they ride them, full taps. Again no break in. Do you think for one second that if break in is so critical to ensure that a motor will not break, that they will skip that step?
Also, bikes that have been run in the hard way, actually make between 5 to 10% more power in the dynos, compared to the ones that was babied. If the heard break in was bad, why would they make more power, and why are the babied bikes down on power.
Maybe it?s time people know the real truth about how to break in a motor. It takes guts, but warm up the motor correctly, and your set to let it rip.
Jakobi
Super Moderator
Hard break in eh Matt 
Then you have dry install vs lubed.
From the pages and pages of right and wrong and this way and that way that I read I baically came to conclude that the rings seat against the barrel and 'bed in' due to pressure on them. This means get a load on the engine to make it happen.
As per my first post. Its anyones guess as to whats 'best' but I just ride it like its any other day. Treat the engine nice until its willing to rev cleanly and then just ride. It kinda falls in place with everything Matt just said. No constant revs, no babying, but not flogging a cold engine sensless. No issues yet for me.
Then you have dry install vs lubed. From the pages and pages of right and wrong and this way and that way that I read I baically came to conclude that the rings seat against the barrel and 'bed in' due to pressure on them. This means get a load on the engine to make it happen.
As per my first post. Its anyones guess as to whats 'best' but I just ride it like its any other day. Treat the engine nice until its willing to rev cleanly and then just ride. It kinda falls in place with everything Matt just said. No constant revs, no babying, but not flogging a cold engine sensless. No issues yet for me.
Zman
Platinum Level Site Supporter
I have successfully used a slightly different variation on what has been posted on 4 stroke engines. AT the bottom I also included some explanation / justification. This process makes sense to me for a 4 stroke engine but I am not sure how well the explanation applies to a two stroke. The main points of this engine break in / work out are as follows.
1. Warm up the engine
2. Find an open area to run. Select a high gear so as to apply a load to the engine for a longer time. From a low rolling rpm, apply WOT and run the engine from low rpm up to some mid upper rpm (70% or max rpm).
3. Once you reach the 70% rpm cut the throttle and let engine braking slow you down to the low starting rpm again.
4. repeat steps 2 and 3 ten times.
5. Let it cool down.
5. Repeat steps 1-3 another 10 times but use 80% of full rpm.
6. Let it cool down.
7. Repeat steps 1-4 another 10 times but use 90% of full rpm.
8. Let it cool down.
7. Repeat steps 1-4 another 10 times but use 100% of full rpm.
8. Let it cool down and change the engine oil.
9. Your engine is broken in.
4 Stroke Explanation - A) the WOT through the rpm range provides an overly rich air fuel ratio that washes oil off the cylinder walls including any break in metal debris. B) the engine braking provides vacuum to a 4 stroke and draws engine oil up into the rings to relube them.
For a 4 stroke engine this makes sense and I have had good results with it.
Regarding the cool down cycles, I have heard that the heat and cool down cycles reduce internal stresses in new metal parts that are an inherent part of the manufacturing process and this helps to reduce the chances of warping the new parts.
I am sure there are many correct answer to this question. I think the keys are; Don't baby it, you need to apply load and make the engine work, it is ok to apply WOT but don?t rev out the engine to max rpm too soon or for too long, don?t let it get too hot and increase the rpm range over time.
1. Warm up the engine
2. Find an open area to run. Select a high gear so as to apply a load to the engine for a longer time. From a low rolling rpm, apply WOT and run the engine from low rpm up to some mid upper rpm (70% or max rpm).
3. Once you reach the 70% rpm cut the throttle and let engine braking slow you down to the low starting rpm again.
4. repeat steps 2 and 3 ten times.
5. Let it cool down.
5. Repeat steps 1-3 another 10 times but use 80% of full rpm.
6. Let it cool down.
7. Repeat steps 1-4 another 10 times but use 90% of full rpm.
8. Let it cool down.
7. Repeat steps 1-4 another 10 times but use 100% of full rpm.
8. Let it cool down and change the engine oil.
9. Your engine is broken in.
4 Stroke Explanation - A) the WOT through the rpm range provides an overly rich air fuel ratio that washes oil off the cylinder walls including any break in metal debris. B) the engine braking provides vacuum to a 4 stroke and draws engine oil up into the rings to relube them.
For a 4 stroke engine this makes sense and I have had good results with it.
Regarding the cool down cycles, I have heard that the heat and cool down cycles reduce internal stresses in new metal parts that are an inherent part of the manufacturing process and this helps to reduce the chances of warping the new parts.
I am sure there are many correct answer to this question. I think the keys are; Don't baby it, you need to apply load and make the engine work, it is ok to apply WOT but don?t rev out the engine to max rpm too soon or for too long, don?t let it get too hot and increase the rpm range over time.
nambo-trev
New member
I'm with you ggman I never break any of my engines in either. My dirt bikes and street bikes have never seen a "break in" period and have run strong and hard everytime. This might have been an issue 20 or 30 years ago but I don't believe anymore. The materials and tolerances are a much higher standard and a lot of guys are no longer paying much mind to break in.
GMP
Active member
There run on a dyno at the factory harder than you can ride them anyway. Most of the ring seal breakin is already done. I run them like I will ride them, with the same Dominator premix, just with frequent but progressively fewer cool down cycles when new. I can't argue with how the parts look when torn down. Little to no blow by @ 100 hrs.
