Overhaul Breakin Tips?

I know this has been addressed in the past and I have looked through past threads but I'm not finding it. After overhaul should I retorque the heads? If so when? How should I run this through the breakin period? How long is the breakin period. At what point should I do my first oil change. Any suggestions would be great.
I have heard ride it like you stole it on breakin. But I'm almost 60 it's been it's been a while since I did anything fast. Well the wife says I'm quick as a rabbit.

Here's what Larry provided me in my first build, have used this every time since with good results....

After you get some miles on it an do a full service...oil & filter, valve adjustment, carb synch, check ignition timing....try to shoot for .004" on intake and .004" - .006" on exhaust. You want the exhaust a thou or two looser than the intakes.

If you want and if you can get it locally, Joe Gibbs Break In oil is excellent stuff. Make sure it's the break in oil and not one of the synthetic blends. They have many blends of Joe Gibbs.

BEFORE YOU BOLT ON THE VALVE COVER TO FIRE UP THE MOTOR....go to the autoparts store and get yourself a bottle of LL2 lifter lube. It's additive to protect the new cams. Web gives you some llube with them but I like to really gob it on the lobes and buckets on a fresh motor with NEW cams.

DO NOT LET THE MOTOR IDLE FOR THE FIRST 30 MINUTES OF OPERATION.

Change oil and filter in 100 miles. No more lifter lube will be needed at that point, just regular, good oil. Kendall 10 -40 has served me well over the years. Then change oil & filter again @ 500 miles, then 1500 miles. Do not use synthetic oil until after 1500 mile mark if desired to do so.

Here's what I do on a new motor and have great results.

When you assemble the head nuts and washer, use NAPA Engine Assembly Grease on the washers & the Nut Threads. Torque to spec. [use it on the cam bolts too]

Then fire up the motor and run it above 2500RPM for maybe 5 minutes with a fan blowing on the engine. You want plent of air so you don't blue the new pipe. Then shut it off and let it cool completely down to stone cold. [even if that's overnight sitting].

Then before firing it up again, set your torque wrench to spec and go over the head nuts one more time. They will probably take some torque. Since you lubed the threads and washers and did not run the engine an extremel long time, you won't have to break each one loose again to retorque.

Then, you're ready to hit the road and have some fun. Remember...keep the RPM above 2500 for a while yet. Go ride the bike, vary the RPM, DO NOT CRUISE AT STEADY THROTTLE OPENINGS. Don't baby it either. On freeway, run her up then left off the throttle, run her up let off the throttle, work those rings in....

After it's warmed up good, run it up there to 6000 in 3rd gear. You'll feel the new power taunting you to pull the trigger!

The following break-in instructions are in the KZ650-C1 Motorcycle Owner's Manual:

0 - 500 miles / maximum engine RPM = 4,000
500 - 1000 miles maximum engine RPM = 6,000

Change oil @ 500 miles

Ed

My first 25 miles went without a hitch except for a small oil leak at on of the cam plugs.

Had my used 750 cam drenched in Torco assembly lube, pistons and rings lubed good and the pump primed. Started in 5 seconds and I let it idle at 2,500 for maybe 2 minutes then after checking it real quick I took it out for 25 miles. Got the choke off after 20 sec or so and even though it was smoking and spitting a little at the start it cleaned out and sounded really good and quiet.

Did some pulls from 4,000 to 6,500 in 4th and 5th maybe 5-6 times and after it warmed a little. After the 25 miles I let it cool over night and re torgued the head. Most were dowm from 28 to 24 or 25 so they tighted up a little and all felt solid and correct when done. Used motor oil on the threads and washers maybe assembly lube would have been better.

I then checked the valves and all were good a few tightned up a thousand or so and a few stayed while a few tighted up only a half a thousand so I'm feeling really good about Jays valve job. Also since I replaced several cam chain rollers with new rubber and a Liska roller I re checked the cam chain adjustment. Probaly will do it again at 100 and 500 also just to be sure.

Plan on 2 or 3 more trips to 100 when I will change the oil and filter. I also need to sync the carbs since I needed to take them apart for o rings and only bench shimmed them, and will do that after the next ride. Will also check timing but the Dyna was easy to set with the lights and I think its realy close.

I plan on switching over to Mobil 4T after 500 miles maybe a little sooner than some but personaly I feel the rings should be close to being broke in at that mileage. I'll then re check the valves again and am thinking it should be close to ready. All in all my first rebuild went good (knock on wood) and hope yours goes as well.

I have read comments by many about not using synthetic when breaking in an engine, but I don't understand how that could be a problem. All the new performance cars come right off the truck with synthetic oil in the crankcase and that doesn't cause any problems. Ed

650ed wrote: I have read comments by many about not using synthetic when breaking in an engine, but I don't understand how that could be a problem. All the new performance cars come right off the truck with synthetic oil in the crankcase and that doesn't cause any problems. Ed

New automobile motors are machined to micron tolerances, that's why they last for 300k+ and require no break-in. The aftermarket just can't achieve the same specs.

As an example, when Ford introduced their 4.6/5.4 modular motor, any head that needed resurfaced had to be sent back to Ford, as no one else could achieve the desired finish.

650ed wrote: The following break-in instructions are in the KZ650-C1 Motorcycle Owner's Manual:

0 - 500 miles / maximum engine RPM = 4,000
500 - 1000 miles maximum engine RPM = 6,000

Change oil @ 500 miles

Ed

The above numbers were actually on the tachometer face of my new KZ-750 with a clear plastic overlay.

650ed wrote: I have read comments by many about not using synthetic when breaking in an engine, but I don't understand how that could be a problem.

I tend to think that's a myth, but I use mineral oil for the first break in because I'm cheap. Since I am going to change the oil after I run it a couple of hours, I am not going to use $40 worth of oil. I think any good mineral oil is OK as long as you add ZDDP. As for using syn, about 99% of the oil labeled "full syn" that is sold in the USA is mineral oil anyway.

Actually, that sounds like a valid reason. Ed