03/13/2026
This very tired and worn Screamin' Eagle 120R top end was treated to a complete rebuild/blueprint the MEGAFLO way!
The 120R heads come from HD with cnc machined port contours. This particular set had some additional "fluff" to the ports and valve seat work done at some time in the past by an unknown facility. They were taken in for rebuild work only and not to address any improvement(s) that would involve additional port work, so after an initial assessment of what was done in the past, a few different tweaks and additional machining steps were required to provide for a high quality, durable and trustworthy finished assembly and otherwise get them where they need to be!
New custom machined valve guides, custom machined intake valves and reconditioned exhaust valves were in order. The AV&V 650 lift beehive springs tension checked right in at as-new specs, so the customer decided to stay with those. After the new guide and seat work was completed, the chambers were then cc'd and decked to both equalize the volumes and "pull out" an extra 2 cc to compensate for the new piston(s) dome volume.
The cylinders were bored and fit to a set of CP Carillo 3cc domed and the head gasket surfaces decked, fresh, flat, perpendicular and balanced height(s). Finally, the top fins adjacent to the exhaust where step machined to provide for easier installation of the exhaust system.
Much more than "just a rebuild" this top end will be returned to the customer with a copy of the most complete blueprint assembly spec sheet in the industry listing all internal clearances, fitments and more for the ultimate in quality control!
MEGA-FLO 45+ years of full time High Quality American V-Twin engine and cylinder head building craftsmanship behind every cut!
