There are 4 aspects to storing a bike. They are fuel, oil, battery and tires. First will be presented the short version of each (what time is it?). Following that will be the highly technical explanations of each, for those who want to know why (how to build a watch).
Fuel. There are 2 different methods. First is to fill the tank with non-ethanol fuel and add a fuel preservative, such as “Stabil” or “Sea Foam”. Add the chemical at the gas pump, then ride the bike home to be certain the fuel in the rest of the system has the preservatives in it. Ride it to be sure it’s warmed up and then give it some hard acceleration to clean the spark plugs before parking it for the winter.
The second method is to drain the gas tank when the engine is hot, (see above on cleaning the spark plugs) then start and run the bike until it quits. This removes all fuel from the system, preventing damage from deteriorated fuel over the storage period.
Oil. Park the bike and leave it. Whatever bad that will happen to the oil over the winter won’t matter, because you’ll change the oil in the spring and start the riding season with new oil. If you’re going to ride it periodically, then stick with your normal oil change schedule.
Note: Whatever you do, DON’T START THE BIKE AND LET IT SIT AND IDLE PERIODICALLY OVER THE WINTER. Park it or ride it, but don’t start it as a means of storage.
Battery. The best thing for a motorcycle battery is to be connected to a device designed to maintain the battery. The brand “Battery Tender” is generally recognized as the standard of the industry and the one sold by most motorcycle dealers. It’s designed to charge the battery periodically. Don’t use a battery charger, as that will simply slow cook the battery until its dead.
Even if you remove the battery from the bike and bring it in the house, it’s still advisable to use a battery tender on it occasionally to keep it fully charged.
Do NOT start the bike and run it to “recharge” the battery. This won’t help the battery and can be very hard on the engine.
Tires. Be sure the tires are properly inflated before storage. Re-check inflation before riding it in the spring.
Attention—Since our motorcycles are members of the family, it’s encouraged to pay attention to the bike from time to time. Cleaning, waxing and admiring will help keep the bike’s spirit up until the spring thaw. Remember, it’s OK to just sit and stare at your bike. That bitch is sexy.
Technical explanations (How to build a watch)
Fuel. Fuel degrades rapidly. It’s actually only “fresh” for days after you buy it. Storing the bike with a full tank will reduce the contact it has with air, which can aid in fuel preservation. Adding products like Stabil or Sea Foam will help prevent degradation of the fuel and subsequent damage to the motorcycle fuel system. Likewise, draining the entire system will also do the trick. If there’s no fuel, there’s less chance of damage.
Auto repair shops have reported substantial damage to fuel pumps from vehicles stored long term with ethanol fuel in the system. Ethanol can be corrosive and result in damage.
Oil. Oil gets worn out from 4 things. The first is acid that develops when super-heated combustion gases from “blow-by” contact cold air in the crankcase. Blow-by is pressure that “blows by” the seal of the piston rings. The metals in the engine change dimensions with temperature. Cold engine parts don’t work properly until full operating temperature is reached. The entire engine was designed to run at a specified temperature range. Cold parts are smaller.
Motor oils have to have additives to neutralize these acids. The more cold starts, the more additives that get used up. At some point, this causes the oil to become acidic and attack the seals and gaskets. This is where oil leaks come from.
The second thing is unburned gasoline that also gets past the piston rings and into the oil, diluting it with liquid fuel. An engine that’s had repeated short run times can actually be seen to have oil level that’s too high. I’ve seen a 4 quart system that was 2 quarts over full from this condition. This meant that the oil was too thin to lubricate and it turned on the oil light as a result.
The third thing is water from condensation on a cold start. Much water is formed when an engine is cold started. This can cause rust and corrosion, in addition to diluting the oil.
The fourth thing is running the engine for extended periods with oil temperatures below normal operating specifications. Getting the oil “up to temperature” means that the moisture and unburned fuel get evaporated away. Water boils at 212 degrees F. at sea level. The normal operating temperature of motorcycle oil is 180 to 220 degrees. It’s important to understand the most motorcycle engines are air cooled. They don’t have a thermostat to regulate temperature like a car. I used a dipstick that doubled as a thermometer to monitor oil temperature on my Harley Fat Boy over thousands of miles to better understand this. It took 10 to 20 miles of riding in cold weather just to begin to get the oil temperature close to specifications in winter temperatures. Idling never got it even close if the outside temp was cold.
For all these reasons, it’s just unwise to think that you can start the engine and run it from time to time and expect good things to happen. Let it sit, it’s far better for the oil and the engine.
Battery—It takes a long time (maybe several hours or more) of slow charging to bring a battery to a full state of charge. When a battery sits in less than a full charge, it sulfates and ages prematurely. Vehicle charging systems were not designed to perform this job in short operational periods.
This is the reason to use a solid state device designed to preserve a battery on your bike. Modern bikes have many drains on the battery. Security systems, the computers that run the ignition and fuel injection, the memory on the radio and more all use electricity to retain memory. This little draw is called “parasitic draw”. Think of driving across the desert with a very small leak in the radiator of a car. It doesn’t matter how small the leak, sooner or later the system runs out of water and you’re done.
Even sitting on a shelf in a nice warm place in your home results in some current loss. This is why the battery needs to be connected to a tender from time to time even if you take it out and bring it inside.
This is the second reason you don’t start the bike from time to time to “recharge the battery”. It doesn’t really recharge the battery properly, anyway. This will only shorten the life of the battery and cause you to think that the brand of battery you have just isn’t a very good brand. The reality is, it was mistreated.
Tires. Inflate the tires when the bike goes into storage, then check the tire pressure again in the spring. Tire pressure is critical, whether stored or riding. Bikes aren’t heavy enough to really flat spot tires, so that’s no concern.
Fast Summary: Fill the gas tank, add some chemicals, air the tires. Hook up a battery tender, then cry your eyes out. Wine has been reported to be helpful to deal with PMS (Parked Motorcycle Syndrome).
—Becky Witt is an ASE Certified Master Automobile Technician (ASE CMAT). She is a nationally recognized expert on motor oils and has presented classes on motor oils for shop owners and professional technicians at several International Events. She produced a DVD on motor oils and sold 200 copies to a major oil company. She owns an auto repair shop and has also taught many classes on repair shop management.