Leaving a motorcycle idle for several months can wreak havoc if precautions are not taken. Here are a few minor things you can do to protect your bike and prevent problems when you’re ready to ride again.
Before storing your motorcycle for any extended period of time, top off the fuel tank with fresh gasoline to prevent contamination. Otherwise, as the weather changes, moisture in the reservoir will condense and form rust.
Failure to prep the fuel system before storage is a common and costly oversight. Gasoline deteriorates over time, and old gas forms deposits that can clog filters, carburetor jets, and passages, and fuel injectors. The phase varies considerably with temperature, fuel blend, additives, and venting, but typically begins around two months after inactivity. Cleaning a fuel system and a set of carbs may cost hundreds of dollars. To avoid this, add a fuel stabilizer, such as STA-BIL (or similar product) sold in motorcycle, auto parts, and boating shops. Follow the instructions on the package, and run the engine to get the chemical into the carbs or injection.
When not in use, batteries become sulfated and cannot be recharged. Alarms, ECM, and radio memories, and other electrical equipment also draw current, which quickens the process. To prevent a battery from being ruined during storage, connect it to a maintenance charger such as a PulseTech or equivalent. These chargers, which are available at motorcycle shops or online, prevent the battery from dying or overcharging. A constant connection to a regular trickle charger, however, will overcharge and destroy the battery.
When used motor oil is left in an engine during storage, moisture and acids created during combustion, along with other crud form sludge and may etch or eat away at metal surfaces (including bearings). To avoid this, warm up the engine and change the oil and filter just prior to putting the bike away.
Liquid-cooled engines require more attention because their antifreeze breaks down over time, eventually becoming acidic and causing corrosion inside the engine and cooling system. When water is added the antifreeze protection is reduced, and if it is insufficient, severe damage may result if the coolant freezes. Coolant should be tested for freeze protection with a hydrometer or test strip before storing the motorcycle, and the cooling system should be cleaned and flushed (and antifreeze replaced) every two years or so.
Tires lose pressure gradually, and leaving them under-inflated may cause flat spots and sidewall cracks, which will shorten their safe service life. Therefore, keep them at the recommended pressures, and occasionally move the bike slightly to help prevent problems. Also, if your motorcycle has a centerstand, use it to reduce some of the weight on the tires. Avoid storing your bike in direct sunlight, as prolonged exposure causes tires to split, crack, become less pliable, and ultimately fail.
The lubricant in control cables may dry out during storage, causing throttle and clutch (where applicable) cables to bind or even break. Grease the cables with a quality cable lube. Special lubrication kits are available from most motorcycle shops.
Clean the vehicle thoroughly, dry it with soft towels, and wax all painted and exposed metal surfaces. If possible, store it indoors, because winter weather can seriously depreciate its condition and value. For those of you who don’t have a place in the house to keep your motorcycle, get a sturdy outdoor cover with a waterproof, snug-fitting design that won’t blow off. If you’re stowing it for more than a few months outside (even under cover) or in a high-humidity area, remove the spark plug(s), add about a teaspoon of motor oil into each cylinder, place a rag over the opening, and crank the engine over briefly to circulate the lubricant. Once you have done this, reinstall the plug(s). Also spray a coating of marine fogging oil (sold at boating stores) over metal components to help prevent rust.
Cycles stored inside can also benefit from a protective shield of breathable material. It will keep dirt off and may discourage children from playing on it. If the area can be accessed by rodents, consider placing traps (unless you have pets or children) to keep mice from gnawing on wires and hoses or nesting. Also, try not to store a motorcycle where someone may trip on it, tip it over, drop something on it, or dent it with a car or house door.