How do you break in rebuilt engine 1340 Harley

top in end went bad some dumb use silicone to put the lower end together. plug up some oil lines. got the bike with 26000.miles on got 30000.on it gone bad . so I am put in new cam,rockarms,push rods ,oil pump ,rings rebuilt top end. lower end check out . so how should I break in the engine.

Like a new one.

{some say break in one why are the harley why}

Do Your Easy 4-5 Hundred Miles, Drop The Oil And Be On Your Way.

EVO break in

I wish I had read your thread earlier...
Are you still breaking it in?
Here's how I did mine and it is solid!!!
under 50 for the first 50 mile,
then just keep the rpms well on the low side (stay under 70)and always vary the rpms.
give it some gas uphill and on the down hill, don't accelerate but don't allow any negative torque on the engine. Change the oil at 500 and then again at 1500 and after that ride the **** out of it

Actually the rings will seat just as fast on deceleration as they will on acceleration - but they won't holding a constant rpm & throttle position. Rings can seat quickly, that's a key issue & a good way to do it is ride a nice twisty back road where you can't hold a steady speed & you can't go all that fast either. The constant on & off the throttle, speed up, slown down on such a road will make the rings seat quick.

Stop & let the engine cool periodically, as "heat cycling" helps break-in a lot too. Parts made of different metals expand & contract @ different rates & by different amounts, but after a while they start to "take a set" & the more times the engine heats up & cools down, the faster that'll happen. Doesn't apply to liquid-cooled engines, but it does to air-cooled engines.

With respect to changing oil, I've done that the 1st day. In the pan I've seen a silvery film on the top of the oil from worn off metal particles so small they go right thru the filter. 2nd change a few days later & there's very little. 3rd change it's completely gone & I've done the 3rd change even before there was 1000 miles on the engine. After that, back to normal change intervals. Once you're satisfied the rings are seated you're in good shape.