Topic: 1982 CB650 Top End

[bryanj]

Change oil and filter at 500 miles then every 1500, no idea where you got 600 from.
Oil should be 10w40 or 15w40, 20w50 is too thick cold.
DO NOT  "baby" or lug the engine. If built to original specs normal running is fine, in facr in the late 70's Kawasaki had problems with oil consumption because people ran in motors too slowly and glazes the bores

[DaveBarbier]

The procedure is probably similar to what you’re used to in the aircraft world.
Don’t let it sit there idling
Don’t baby it or go for highway runs with a sustained RPM.
Vary the RPM a lot.
Third gear up hill rolling on the throttle is good as is engine breaking from higher RPMs.
Very high RPMs isn’t inherently bad for a new motor but avoid it until you know you don’t have leaks or weird noises and good top end oiling. I worked up to redline that same day.
I changed my oil the first time after about 150 miles and readjusted my valve tappets. They will be out of spec if you had a valve job done. If you did, continue to monitor them until they level out too.

You can look up places that do engine break-ins on a dyno. After a few pulls they’ll wind it up high and you can watch the HP increase each time.

[aircraftgrade]

Change oil and filter at 500 miles then every 1500, no idea where you got 600 from.
Oil should be 10w40 or 15w40, 20w50 is too thick cold.
DO NOT  "baby" or lug the engine. If built to original specs normal running is fine, in facr in the late 70's Kawasaki had problems with oil consumption because people ran in motors too slowly and glazes the bores

600 miles is from the service schedule listed in the Honda FSM for the bike. 20W50 is also called out as an acceptable oil in the FSM...I was more concerned about mineral oil vs. synthetic. It seems straight mineral oil is what I'm looking for so I'm going to stick with that. Thank you.

DaveBarbier, thanks for the valve adjustment note. That's a good idea.

[bryanj]

600 might be first service and then some later Hondas went to 6000 servicing so that could me a misprint, didnt do many 650 as they wernt that popular here. Personaly a wouldnt go more than 2000 or anually

[DaveBarbier]

There are specific break in oils you might consider using. It’s usually 10w-40 and high in zinc. It is also cheap since it will only be in the motor for at most a couple hundred miles. I’ve only heard that synthetic is not good for break in because it’s so slippery that it doesn’t let the rings bed in as well as conventional does.

Do a search on this site for break in procedures, many topics on it with differing ideas and techniques. None of them have done extensive double blind testing with multiple exact motors doing different break in techniques and comparing results. It’s all “I do it this way and haven’t had a problem” not very scientific. The large takeaways are varying RPM to load up the engine, a swift oil and filter change since there will be a lot of suspended particles and don’t go too high in RPM until you know you have good oiling and your motor was assembled correctly.