I use special breakin sessions on any new engine, especially bikes or sports cars, before I ever drive it normally. I vary everything throughout the ranges, except NO redline at first. I make sure everything is warmed up to operating temp and choke off before riding at all. I go easy through the gears one time, and back down easy through the gears. Then hard through the gears but not quite full throttle, and shift at 80-90% redline, and back down hard through the gears with engine braking. Repeat this a few time alternating hard and easy through the gears. Then shut it off, and let the bike cool off completely.
The next time I warm up completely, repeat the 1st 2 steps, and then change the routine slightly. In 1st, accelerate, decelerate, accelerate, shift to 2nd, accelerate, decelerate, accelerate, shift to 3rd, accelerated, decelerate, accelerate, shift, etc. I then repeat all 3 steps a couple more times, varying the rate of acceleration, deceleration, and engine braking, and then let it cool off completely again.
Then I warm up completely, and do the same scenario, but on step 3 I cruise for a little period of time at the top and bottom of the rpm range after each acceleration and deceleration in each gear. Not at redline or lugging, but at high rpms and low rpms. After going through this whole sequence a couple of times, I let it cool completely down again.
I try to do this sequence at least a couple more times before I hit the road for real rides. I extend the cruising time in each gear each time so that the sessions are longer each time. I also get closer and closer to redline each time. I still warm it up completely before each session, and let it cool down completely after each session.
When the special sessions are over, and I don't feel that I need to cool it completely down after each session, I hit the road for normal rides to wherever I need or want to go. I still vary the acceleration rate, as well as the rpm and speed throughout the normal riding range from 35-65 mph in 3rd-5th gears. If there is no traffic, I just cruise for a while in 3rd and vary the speed from low to high rpms, then shift, and do the same in 4th and 5th. If there is traffic that I need to maintain a speed with, I just vary the gears. If driving at 35-40 mph, I use 3rd for awhile, and then 4th for awhile, and keep shifting ever so often to change the rpm even if the road speed is relatively constant. At 55 and above, I go between 4th and 5th. At 45-50, you can use 3rd, 4th, and 5th. You just want to avoid lugging or redline, and vary it as much as possible otherwise.
I usually change the oil a couple of times during the breakin. First after 10-20 miles during the special sessions. Then between 50-100 miles after the special sessions, and/or maybe the first real ride.
After the 2nd oil change, I run one more special session shifting at redline in each gear through all 3 steps, a couple of times, and cool down completely. I continue to vary the speeds and rpms on all rides, but now I try to hit redline in each gear whenever possible. I change the oil for the 3rd time at 600 miles, and do the complete first service, including valve clearance check/set. All the breakin is done on 10w40 dinosaur oil, NO synthetic. I consider the bike broke in after 600 miles and 3 oil changes, and then drive it like I stole it, because that is just the way I ride, but I still run one more 1000 mile cycle on dinosaur oil.
After breakin and 1600 miles at the 4th oil change, I switch to Royal Purple 20W50 viscosity full synthetic. On the Rebel, without an oil filter, I change the oil every 1000 miles from then on, or more often depending on how much I ride in a season.
Harley recommends 500 miles for the breakin service, but I use the exact same procedure on them. The Harley also has an oil filter, and they recommend oil changes every 5000 miles after breakin, but I use 3000 miles max after I switch to synthetic, and usually change it more often than that depending on how much I ride in a season.
This may seem extreme to some, or even most of you, and you probably think I'm just a little anal. You are probably right except that I am a lot anal. However, I know that as soon as the bike is broken in, I am going to ride it to the limit every time that I get on it, because that is what I do. I don't think that you can baby a bike, or any engine through breakin, and then start ragging on it. If you plan on running it to redline regularly, or for extended periods, then you need to spend a little extra time breaking it in right, IMO. I haven't lost any street engines that I broke in myself, and I don't have any that use oil either, so I guess it works.