If you're not going to be riding your motorcross bike in the winter, then you need to store it. Improper storage is one of the fastest ways that motorcross bikes get ruined or need parts replacement. To keep your motorcross bike in good working condition, just store it properly and in the spring it will be ready to take you riding again.
Getting your motorcross bike ready for winter storage is easy. First make sure you have a cool, dry place to store your bike. A basement with no water seepage or your garage are good bets.
First empty the oil. Just warm up your engine and drain all the oil out. After the reservoir is drained, refill with clean oil. Remove the battery of your motorcross bike and store in a dry, warm place. Put papers underneath the battery as it can be corrosive if it happens to leak. It's a small possibility, but you can save yourself a lot of headaches by just preparing. Next, take out the spark plugs, put engine oil in the cylinders and then replace the spark plugs. Drain your gas tank and carburetor bowls.
Next, protect the exterior of your motorcross bike and wax all the painted areas. This will keep the surface protected and keep the paint bright. Prop up the back wheel of your motorcross bike and put the wheel up on a wooden or cinder block. Put a piece of wood or thickly folded cardboard under the front wheel so it is not resting directly on the ground.
You can finish off your Winter storage by covering your bike with a good quality car cover to further protect your bike during storage. When you're ready to ride in the spring, simply uncover, put the battery back in place, fill your gas tank and you're ready to ride your motorcross bike!