Bishop's Performance

Although we specialize in performance, we have a full service department capable of handling all of your bike's needs. From scheduled maintenance and tune-ups, to cylinder boring/honing, flywheel repair and truing, case boring, Timken bearing conversion, tire replacement, collision repairs, restoration, complete engine and transmission rebuilding, installing chrome accessories, welding, head porting, and Dyno-tuning - We can do it all!

	Do you have a set of "shifted" Twin Cam flywheels? You may not have to replace them! If there is nothing else wrong with them, we can true them and weld them so they won't shift again.
Check out our "Prices" page for some of our most common services and parts.

Come on in! Dyno testing & tuning The dyno room
Shaggy doing some welding True & Weld flywheels Timken case bearing conversion Wilton Mill
case boring cylinder boring Coats Tire Machines blast cabinet welding Twin Cam flywheels
50-ton hydraulic press head-porting tools valve refacer Bill at the flow bench milling heads .

Spark Plug Indexing

One of the simplest ways to improve the combustion in your engine is to index the spark plugs. Indexing the plugs ensures that the gap is facing the combustion chamber. If the gap is facing out of the chamber, then the spark is shrouded from the majority of the fuel/air mixture. When the gap is facing in to the center of the chamber, the fuel/air mixture will burn more quickly and completely.
The easiest way to accomplish this is to mark the insulator or metal base with a felt tip marker showing the location of the electrode. Install the plugs and torque to specs.
It's best to have the line fall between the two head bolts. If they are not within this range, try swapping the plugs from the front head to the rear head and vice versa, and they will usually come pretty close.
We sell indexing washers in 4 thicknesses for both the 12mm and 14mm plugs, but they are rarely necessary. While some people may notice a difference in their engine’s performance, most will not. As a general rule, we recommend replacing the spark plugs with new standard Harley plugs every 5,000 miles.

spark plug improperly indexed - gap is facing away from the valves

spark plug properly indexed - gap is facing the intake valve

spark plug properly indexed - gap facing the intake valve