Top End Refresh: Part One | Branch-O'Keefe Head Porting/Polishing


Top End Refresh: Part One | Branch-O'Keefe Head Porting/Polishing - Hot Bike Magazine

01. Here is the about-to-be-dissected '95 Road King with a stock 80ci Evo that's getting the top end freshened up with new heads from Branch-O'Keefe in this issue. Look for the rest of the components going on in the next two issues.

02. Remaining in between the framerails will be completely updated versions of the stock cylinders that will be bored and honed, but for this article we're focusing solely on the cylinder heads, which we gave to Branch-O'Keefe owner John O'Keefe to work his magic by giving the carbon-coated heads the #4 head treatment, which involves reshaping the combustion chamber to give them the legendary bathtub shape, larger valves, as well as porting and polishing the heads to help flow more air to the engine. This process more or less made the company one of the best in the biz when it comes to engine components.

03. Next issue we'll show you an in-depth article where these cylinders get bored and honed to accept the larger pistons by Eric Bennett from Bennett's Performance.

04. With the top-end components (cylinders and heads) removed, we were ready to make the long 20-foot trek from Bennett's front door to Branch-O'Keefe's shop to get started with the head porting and polishing.

05. You probably wouldn't want to eat off of these. The crusty old heads were in desperate need of a tender touch. John removed the stock valves, valve guides, valve springs, and keepers in order to put the heads in the bead blaster to remove the carbon that had built up over the course of its 15 years and 60,000 miles. Man, that's a lot of build-up!

06. Once the carbon particles were removed via the bead blaster, John forced the stock valve seats out with a 12-gauge shotgun. Actually, he used an air hammer to force them loose, and after that was done, it was on to welding the new bathtub chamber.

07. The master at work; John adds plenty of material via the TIG welder to start the reshaping process of the stock Harley combustion chamber.

08. John added a lot of material to the chamber that has taken on the bathtub shape.

09. John keeps an assembly line of mills to save time from changing bits and switching up measurements. Here John cut 0.030-inch from the deck surface, when all is said and done a total of 0.050-inch will be cut from the surface.

10. This mill was used to re-cut the combustion chamber to fit the larger valve seats.

11. Here are the larger Martin Wells valve seats ready to be installed (the larger at right is for intake, the smaller is for exhaust).

12. To stuff these puppies in, John heated the heads with a torch and put the valve seats in the freezer so that when they're mated, the expanded metal from the heads mates perfectly with the cooler metal of the valve seats.

13. John delicately smashed the valve seats in with a sledge. Actually, just a few taps, and because of the difference in metal temperatures, the valve seats mated to the ports fairly easily (sometimes they fall right into place, according to John).

14. Then the heads were ported, which is the most important process. Basically, the ports were treated with a pneumatic rotary file that removed material to flow more air via the intake port into the combustion chamber and out the exhaust port. John employs skilled craftsmen that do nothing but port heads all day long. The ports were then polished to flow the increased air velocity more smoothly. The combustion chamber will be polished later.

15. John installed the Kibblewhite valve guides into the heads. The Kibblewhite valves provide great lubrication and last a long time due to the bronze manganese material.

16. Here John used a specific cutting tool to cut three angles in the valve seats: 60 degrees, 45 degrees, and 30 degrees, that all correspond to multiple valve opening clearances. This is another key components to the Branch-O'Keefe design.

17. To protect the valve seat from being damaged, John placed a dummy valve into the valve guides and the combustion chamber was polished to a high sheen.

18. It was then time to lap the valves with lapping compound. This is basically the finishing touch to finally mate the valve to its respective seat. Lapping compound is tiny bits of carbide mixed with grease and it's available in many different grits. John used a 180-grit lapping compound to finally seat the valves before moving on to final assembly.

19. Once lapping was done, the new valve stems were lubed up and installed into the heads with Viton oil seals (arrow).

20. The springs and top and bottom collars were then installed, all held in place with keepers.

In Depth
If you're still running a stock Evolution motor in your Harley, you might want to think about opening it up and stuffing it with some new guts. A few years ago, we freshened up the top end of a Harley dresser's Twin Cam by giving the cylinder heads to Branch-O'Keefe to be ported and polished while the cylinders went to Bennett's Performance to be bored and honed. The shops are located literally next door to each other in Signal Hill, California; in fact they share walls, so it's very convenient for any potential performance customer, especially with their extensive wealth of engine and overall motorcycle expertise.

We currently have a '95 Road King still running the stock Evolution engine with more than 60,000 miles on the clock. It was time to revisit the legendary head porters/polishers, Branch-O'Keefe. The company's Type #4 heads ($950) feature a bathtub chamber design and a porting and polising treatment that flows air more freely and unobtrusively. Air/fuel flow imporves and the smaller combustion chamber causes higher compression and more power. Also larger valves and valve seats are added which also help the heads flow more air overall. Jerry Branch founded the company in 1969, and John O'Keefe came on board in 1974, and is now the sole owner of Branch-O'Keefe. All in all, John has refinished more than 100,000 heads in his career!

One thing definitely worth mentioning is that John's focused a lot of attention on helping the US's struggling economy by trying to bring in new money from overseas (mostly Japan) through selling the legendary heads with parts made only in the USA. The money he receives from overseas he then injects back into local businesses to keep the cycle of parts production going. John is a good guy and is doing a very honorable thing, and he only buys/uses American-made products.

In this first installment of a three-part series, we'll focus on the head porting/polishing process that made Branch-O'Keefe famous. Tune in next month when Eric Bennett from Bennett's Performance shows you how he bores and hones the cylinders to make room for oversize pistons, which brings us to the last installment with +.005 pistons from JIMS, along with new lifters, adjustable pushrods, breather gear, and chrome head bolts. Also being installed will be a new Andrews EV27 camshaft, which when used with Branch heads, provides a smooth increase in power throughout the power band, especially for baggers, according to Branch-O'Keefe. Everything will be sealed up nice and tight with a top-end gasket kit from Cometic Gaskets.


Andrews Products
(847) 759-0190 |

Bennett's Performance
(562) 498-1819 |

(562) 597-2850 |

(800) 752-9850 |

(805) 482-6913 |