Normally, I replace ALL rubber/plastic hoses on my trucks, cars, boat motors etc about every 6 to 8 years regardless of mileage but I have forgotten about the Road King so, does anybody know of ANY “most likely to fail” hoses that are hard to see/find? I’m going to change everything I can see but not certain what’s under the gas tank.2003 RK 66000 miles

 

Hose from the oil tank to the oil pump, return hose from the engine to the oil tank, breather line from the engine to the oil tank, and oil cooler hoses if applicable.
Fuel hose, gas tank crossover hose, gas tank overflow hose, gas tank grommets, air cleaner breather hoses (if applicable).
Brake hoses.
Crankcase vent hose.
More rubber/plastic parts:
Spark plug wires.
Throttle cables and clutch cable.
Brake caliper bleeder screw caps, valve stems on wheels.
Windshield grommets, rubber bumpers, well nuts, rubber motor mounts, battery pad.
Floorboard pads, brake pedal pad, shifter pegs, foot pegs (if applicable).
Rubber and plastic connectors of helmet(s).

 

 

The front and rear master cylinder cover gaskets as mentioned by hoginedgewood are two vital items!
Both not so obvious, and both I have had to replace due to lack of aggressive preventive maintenance. I now change them yearly.
(Over time the brake fluid deteriorated the rubber gaskets, causing them to leak. Brake fluid ate away the paint around the master cylinder base and cap.)
Tires are also noted. Rubber hand grips are another "in plain sight" item. I made a cover for mine with a thin piece of leather (from my local auto upholstery shop) and laced with a flat shoestring.

 

The front and rear master cylinder cover gaskets as mentioned by hoginedgewood are two vital items!
Both not so obvious, and both I have had to replace due to lack of aggressive preventive maintenance. I now change them yearly.
(Over time the brake fluid deteriorated the rubber gaskets, causing them to leak. Brake fluid ate away the paint around the master cylinder base and cap.)
Tires are also noted. Rubber hand grips are another "in plain sight" item. I made a cover for mine with a thin piece of leather (from my local auto upholstery shop) and laced with a flat shoestring.

 

Wow I thought I was a bit over the top with replacing parts under maintenance.

Is this a southern thing with the heat? I can't imagine doing this on a auto. I would expect 20 years or more.

 

I have been detailing cars since 1966 and Harleys since 1969. You see things others miss.

 

I don't doubt, it is a good thing to do. I am curious if more a problem in the south. I do carry hoses on my bikes. They are all over 10 years old now. But out of the sun.

 

Tom Ort (Tom's Custom Cycles Yorktown VA) taught me that heat from the engine is the main cause of oil hose failure. The oil gets hot and degrades the hoses from the inside. We are lucky to spot a swollen or spongy hose before it suddenly fails. Throttle cable housings may show no wear, it is usually the actual wire cable inside the housing that frays and breaks. Grime and chemicals on the road cover the entire bike causing unseen degradation. I schedule and replace wear and tear parts by systems, e.g., Brakes, Fuel, Electrical, Exhaust, Chassis, etc., on a rotating basis. The H-D Touring Model Service Manual has a Service Interval Chart, and I use it as a guide for maintenance and parts replacement.
Every Thursday afternoon I give it a bottom to top hand wash, then blow dry with a Metro Vac Air Force Master Blaster Car & Motorcycle Dryer. I visually inspect my clean bike, check the tires and the kickstand. Monthly I wax it using quality off the shelf products. Quarterly I check all the fasteners. I always check the oil and transmission fluid after every ride.