more ring break in

The break in is done by using the gas pressure rather than the spring in the rings to seat them. However, what happens when turning it over by hand when setting timing and valve clearance etc on a fresh bore? Is it a plus or a minus? It seems like it would be the optimum because everything is dry. Or should all that be kept to a minimum leaving the break in for a running motor? Or does it matter at all? One step further...if it was turned over 2000 times while dry and fresh would anything be gained?

assemble the rings dry. Get all other settings correct and ride the bike pretty firmly, varying the pressure. dont know why you guys piss around with crazy theories.

I suppose it was guys pissing around with crazy theories who came up with dry assembly of the rings.

dry rings. oily rings.... the debate has as much utility as one about the best oil to use

I'd be more concerned about what's happening to the valve train while you're turning it over by hand. Fire it up as quickly as possible, and go ride.

Nathan

For years I've assembled rings and pistons with only a light coat of WD40 on the ring lands and piston skirts. I started doing it back in the 90's, racing 883 Sportsters. To get the best leakdown, we finished the bores at 600 plateau hone, and the only way the rings would take a set was to assemble dry. The combination of fine bore finish and a history of high-end synthetic race oils remaining in the pores would prevent a timely breakin any other way.

I never scuffed a skirt this way, either. Start it, when the cylinder starts to warm to the touch, shut it off and let it cool. The next time, use it as hard as you like. Rings are in.

It is critically important that there be some sort of lube on the ring lands. If not, the hot rings can stick to the piston and micropit the lands-and the lower ring land is 75% of your bore leakage.

Oil everything. Run it for a ride as you would drive. Shut down and re-torque. Exhaust nuts too. Ride again.

Even if you do assemble the pistons dry, isn't there an "oil storm" in the crankcase as soon as the engine starts?