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.
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 ½ 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 ½ the RPM range of the motor. Example. If the red line is at 10 000 RPM, don’t exceed 5000 RPM. Once you reach ½ RPM range, change gears like normal followed by full throttle again. Change gears at ½ 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 ½ RPM, you change gears at ¾ 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.
