How To Winterize Your Motorcycle

Evans Brasfield
by Evans Brasfield

Baby, its cold outside!

The sad truth about motorcycles is that they need special treatment if they’re going to sit for even just a few weeks. The gas in the tank and the chemicals storing electricity in the battery are the first to suffer, and both of those are important for getting your bike back underway. However, many other things can accelerate the wear on your motorcycle if you don’t take care of them before an extended hibernation. Unfortunately, many riders don’t winterize their bikes for the off season and are greeted with an ugly surprise come springtime.

Gas Tank

Sealed containers such as gas tanks form their own internal micro-climates. If you’re going to park your bike for more than a week, completely fill the tank. Otherwise, as the temperature rises and falls, any moisture in the air will condense on the bare metal inside the tank and can cause rust.

Fuel stored for long periods can stratify into its components unless a fuel stabilizer is used. Be sure the tank is completely full, or the moisture in the air trapped in the tank can cause it to rust. Cylinder walls, like the inside of gas tanks, need to be protected from moisture or they may corrode. Spraying fogging oil into the cylinders can prevent this.

If you’re storing your bike for the winter, you have two choices for how to prepare the tank. Both methods of tank winterization require that you begin by draining the tank. This is a good maintenance procedure, anyway, since any crud or moisture that has collected during the riding season will be carried out with the fuel. The easiest option is to then pour a fuel stabilizer, like Sta-Bil, into the tank and then fill it completely with fresh gas. Honda recommends the full-tank method for all its fuel injected bikes, and other manufacturers will most likely agree. The alternative for people who can’t or don’t want to store their bike with a full tank is to pour a few ounces of heavy oil — 50W at a minimum — into the empty tank. Close the tank and spend a few minutes rotating it until the oil has coated the tank internals and washed away any fuel remnants. Pour the remainder into your oil-recycling container. Next spring, empty out the oil that collected in the bottom of the tank before filling it with fresh gas. Always store your bike with the petcock turned off to prevent any accidental leakage.


Batteries don’t store electricity. Instead, batteries store the chemicals necessary to produce electricity. If left unused, lead acid batteries will naturally discharge. Both high and low temperatures will accelerate this loss of charge, and if it’s allowed to continue, the battery will reach a deeply discharged state that can dramatically shorten its life. Add a constant drain from an alarm system, and your bike’s battery can be stone dead in only two weeks. (Note: If you have a lithium-ion battery installed in your motorcycle, ignore this section of the article. Simply remove the battery from your motorcycle and store it inside out of the cold for the winter.)

A smart charger keeps your battery in good health. You can’t expect a battery to work after several months of neglect, particularly if stored at a low temperature.

Although battery technology continues to improve, producing ever more compact and powerful packages, the only way to maintain a motorcycle battery is to charge it periodically. Fortunately for those of us with lead acid motorcycle batteries, “smart” charger technology has advanced to the point that buying one can pay for itself in a year or two of ownership. You don’t even need to remove the battery from your bike. Just plug it in and forget about it. A fused cable tucked safely out of sight will work fine. However, if your bike will be stored in a sub-freezing location, you should let the battery spend the winter in a less stressful environment.

Intelligent chargers constantly monitor the state of a battery, and when the voltage drops, the charging feature kicks in. Once the voltage rises up to the proper level, the charger enters “float” mode, where a neutral charge keeps the voltage from dropping. The difference between these chargers and the basic trickle chargers that can be bought for less than $10 is the float mode. Trickle chargers just keep trickling away regardless of the battery’s condition, which can do as much damage as not charging the battery at all.

Finally, any non-sealed battery (yes, they are still made) should be topped off with distilled water every month or so, if necessary.


The internal combustion engine is a toxic environment. The oil that is the lifeblood of the engine must suffer through high temperatures and extreme pressures – all-the-while carrying away the by-products of those thousands of explosions per minute. Once the engine stops running, those contaminants settle out of the oil and can sink their teeth into unprotected metal. However, a quick oil change prior to parking your bike for the winter will pay big dividends in the longevity department. Once the oil has been changed, ride your bike for a couple of miles to make sure the new oil has thoroughly flushed out any remaining contaminants.

Although many sport bike cylinder walls are now coated with alloys rather than lined with iron, you’ll still want to protect them from moisture contained in the air trapped in the chambers. Some people prefer to remove the spark plugs and squirt some 50W oil into the spark plug holes. Crank the engine over a few times to coat things before reinstalling the plugs. Another method is to spray fogging oil into the spark plug holes, which may give the cylinders a more thorough protective coating. Fogging oil can be found at many auto parts stores.

You may want to cover the airbox and exhaust openings to keep dirt and critters out. Rags or tape will work fine on airboxes. Exhausts can be covered with a plastic bag and a rubber band or with half of an old tennis ball. Some thorough riders spray WD-40 into their muffler as an extra precaution (because of its water displacing qualities) before plugging it.

If your bike will be stored in an unheated garage that may see temperatures below freezing, you’ll want to check to see that the antifreeze is up to snuff. If you have any doubt, replacing coolant is much cheaper than replacing a cylinder head. (Don’t forget to dispose of the antifreeze properly.) Riders who take their bikes to track days should keep in mind that, if they swapped the glycol coolant for Water Wetter or any other non-anti-freeze based coolant, their cooling systems will freeze at 32 degrees. Completely draining water-filled systems prior to parking them in freezing conditions will prevent damage. Just be sure to stick a big note on the triple clamp or speedometer warning that the radiator is empty.


Although carburetors are seldom found on new motorcycles these days, there are still enough carbureted bikes out there in the wild that including them in any winterization list is still quite necessary.

While owners of fuel-injected bikes don’t have to worry, carburetors can gum up over the winter if they aren’t drained. Periodic float bowl draining also removes any garbage that collects there.

Carburetors have many small and tiny orifices that clog easily and resist cleaning. Gasoline is made up of many compounds, some of which are quite volatile (for easy starting and less pollution). Unfortunately, this means the vast majority of gasoline’s components will evaporate, given enough time, leaving behind varnish in places that you definitely don’t want it. To prevent build-up of this stuff, any time you are going to let your bike sit more than a week or so, you should drain the float bowls. Otherwise, the potential consequence is a time-consuming and/or expensive repair.

The best way to drain the float bowls is to attach a hose to the nipple at the bottom of each float bowl. Then loosen the drain screw and let the fuel pour into a clean container. Examine the contents for water, rust or any other contaminants. (If you find any, you’ve got a nice winter tank-sealing and carb rebuilding project!) Unfortunately, the tight packaging on most sport bikes makes this a time-consuming process in which several parts, like the tank, need to be removed. So, you might not find this method practical for intermittent short-term storage.

The second-best way to drain the carburetors is to close the petcock with the engine running (which you should do any time you’re parking your bike for more than a day, to avoid the possibility of fuel overflowing from your carbs and hydraulically locking the cylinders.) Once the engine has run dry, the carbs are safe against fouling from evaporation. Remember, though, you haven’t cleared the float bowls of other forms of contamination and should drain the carbs properly at least once a year.

A soft cover will protect your bike from dust and paint fade from light. Elevating the tires off the ground keeps them from developing flat spots on the tread.


Bike and tire manufacturers generally agree that it’s preferable to store a bike on stands, to prevent the tires from sitting on the same spot for several months. When storing on stands, reduce the tire pressure by 20 percent. If this is not an option, fill the tires up to their maximum recommended pressure and check the pressure every month. Periodically rotating the tires so that the bike’s weight rests on different portions of the tread is also helpful. Finally, since ozone ages rubber, store your bike away from electric motors, such as refrigerators.

Chassis and Finish

Preparing your bike for hibernation is a good time to perform some of the annual maintenance listed in the factory service manual. Brake and clutch hydraulic fluid replacement and chassis lubrication is a good place to start. Pay particular attention to the cables and the chain. They will benefit from a protective layer of grease or other lubricant.

Similarly, washing and waxing your bike prior to storage will help protect the finish. Apply a heavy coat of wax and don’t buff it off until spring. You can also spray the engine and other bare metal parts with S100 Corrosion Protectant. Finally, cover the bike to protect it from dust and grit. If your bike is stored indoors, make sure you use a breathable cover. Bikes stored out in the elements need a hardy cover like those from Dowco.

[This article was adapted from Evans Brasfield’s book 101 Sportbike Performance Projects. Learn more about it here. Read the MO review here.]

Evans Brasfield
Evans Brasfield

Like most of the best happenings in his life, Evans stumbled into his motojournalism career. While on his way to a planned life in academia, he applied for a job at a motorcycle magazine, thinking he’d get the opportunity to write some freelance articles. Instead, he was offered a full-time job in which he discovered he could actually get paid to ride other people’s motorcycles – and he’s never looked back. Over the 25 years he’s been in the motorcycle industry, Evans has written two books, 101 Sportbike Performance Projects and How to Modify Your Metric Cruiser, and has ridden just about every production motorcycle manufactured. Evans has a deep love of motorcycles and believes they are a force for good in the world.

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  • Jeff benson Jeff benson on Jan 06, 2018

    Usually just some stabilizer and a battery maintainer seems to do the trick. Depends on climate I think. We have a 4 month winter but except when it's snowing the climate is dry. I once tore down a KZ750 that I'd used for several years to replace the cam tensioner and the internals were all nice.

  • Bob Boonstra Bob Boonstra on Jan 19, 2018

    Good ideas generally and I would follow most of these. One thing I would NOT recommend is the use of fogging oil! I did this once on a Honda Goldwing and then couldn't get the engine to run on all cylinders in the spring. I eventually discovered that the fogging oil had ended up on the valve guides and caused some valves to stick open! Only by eventually heating up the engine on the cylinders that would keep the engine running roughly was the normal valve action eventually restored. If the intake and exhaust are sealed on an engine stored in a dry place, then no oil needs to be added to the cylinders.