How to break in a new top end????

[jvogeljr2002]

Whats the best procedure for breaking in a new top end. New Cylinder, Piston, rings and such.

 

[mongial]

The way I have always done it (it may be wrong but I have never had an issue) is.....
1) Ride it easy going through the RPM range but don't hold it open.
2) Put about 2 or 3 tanks of gas through it this way
3) Romp away!

 

[trial_07]

Here is the, IMO, the best way:
1- Start the bike and let it warm up in idle. Stop the bike and let it cool down.
2- Once the bike is cooled, start it again and ride it in all ranges (high, med, and low). Stop the bike and let it cool down again.
3- Repeat step 2 a few times

 

[jason33]

ride it easy for a tank -most ware is done in the first half hour id say,because of the heat up and ware
just dont hold it wide open youll burn the new rings and bore up,possibly gall up the cylinder

 

[trial_07]

I don't agree. You need to warm it up, cool it down, and run the bike through all RPMs. If you ride it slowly and carefully, when you're going to twist the throttle you will have problems and that's for sure.

 

[illcr250]

I don't agree. You need to warm it up, cool it down, and run the bike through all RPMs. If you ride it slowly and carefully, when you're going to twist the throttle you will have problems and that's for sure.

i 2nd that because i have done it lol :)

 

[trial_07]

Resolved unanimously...

 

[dan druff]

Here is a pretty good guide i have used from another site

1) Assemble the engine properly and torque all fasteners to specs.

2) Start the engine with the bike on a stand and allow the engine to come up to operating temperature (top of the raidator hot to the touch). Do not allow the engine to run at one RPM at all. Constantly vary the RPM and do not allow the engine to idle. When then engine reaches operating temperature (about 3 to 5 minutes of running time), shut it off.

3) Let the engine cool completely (at LEAST one hour). You want the engine to be dead-stone cold. Longer is better.

4) Start the engine with the bike on a stand and allow the engine to come up to operating temperature (top of the raidator hot to the touch). Do not allow the engine to run at one RPM at all. Constantly vary the RPM and do not allow the engine to idle. When then engine reaches operating temperature (about 3 to 5 minutes of running time), shut it off.

5) Let the engine cool completely (at LEAST one hour). You want the engine to be dead-stone cold. Longer is better.

6) Start the engine with the bike on a stand and allow the engine to come up to operating temperature (top of the raidator hot to the touch). Do not allow the engine to run at one RPM at all. Constantly vary the RPM and do not allow the engine to idle. When then engine reaches operating temperature (about 3 to 5 minutes of running time), take the bike off the stand and put it in gear. Take it for a ride. During this ride you want to keep the engine under a load at all times. Do not coast. Do not let the bike idle. Do not allow the engine to stay at one RPM. Riding on a mild slope is fine for this, as is slightly dragging the rear brake the entire time. Do this for about 15-20 minutes. Then shut the bike off.

7) Let the engine cool completely (at LEAST one hour). You want the engine to be dead-stone cold. Longer is better.

8 ) Re-torque the head and base nuts.

9) Go ride.

The cool-down steps are crucial to this operation. You must let the engine cool completely for the break in process to work properly.

Also, do the warm up procedure I outline here before EVERY ride. Your top ends will last much longer if you do.

 

[jvogeljr2002]

Thanks Guys

Thanks for the input, this is going to help me out quite a bit. I have done heads before with bikes I had as kid, but now that I am older and a bit wiser, I am trying to do everything properly.