You could let loose once in a while. Just don't over do it. You want the ridge in the cylinder walls to be at the most minimal. Try to keep the engine under 5k at least for the half of the break in. Then you can open up a little bit more to say about 9k. Just remember to don't ride at a constant RPM. You want to get those parts to break each other in nice and good.
holding a constant RPM for too long can cause a lot more problems then letting it loose from time to time during break in. Don't go redlining it all over the place, but if you are on the highway, shift gears from time to time to get the rpm's higher or lower.
It's next to impossible to go by the break in recommendations. To not break 4k rpm's, you wouldn't be able to get over 50 mph. Don't exceed 4k too much, but they key is to vary your rpm's like Greenenvy said. Goose on it here and there but don't redline it. It's bulletproof but take it easy the first 500.
It's all about flexuating the rpm's, you can't hold it too long at a certain rpm. I never took mine over 7500 during break in. Yes as soon as you do your 600 mile service you can slowly start taking it higher in rpm's. I didn't acually beat on mine til around 1500 miles. [:Agree] with David.
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