"My engine seized!"

It's as bad as it sounds and don't get it confused with sneezing. Mostly bearings seize on a dirt bike or ATV but when you hear the dreaded words of a seized engine that could also mean the piston. A seized engine or anything else that contains bearings means a complete shutdown. Therefore, when an engine or the transmission seizes it's much like hitting a brick wall for that part.

Take two BBs or marbles, press them tightly together and move them in opposite direction. You'll not only get a nails on chalkboard sound but an idea of what happens when bearings stop functioning properly. The following major components include bearings:

  • Crank
  • Suspension linkage
  • Transmission
  • Water pump
  • Steering stem
  • Wheels

When bearings or the piston seize, either the engine stops working completely or the functionality of the bearings cease. In either case, your day is finished and you'll need replacement parts. Sometimes you'll hear it sometimes you won't. In the event of a seized piston or crank bearings, if it's timed just right as you hit a jump you're in trouble. When the engine stops working you lose rotating engine mass often resulting in an endo. That sends you flying over the handlebars.

Some symptoms emerge prior to this somewhat catastrophic event that should clue you in on pending trouble. Noise usually persists when the crank, transmission and water pump bearings reach their limits. Wheels on the other-hand feel loose and present a side-to-side movement. Expect harder turning and less fluid maneuverability on the front end when the steering stem bearings grab. Shot suspension linkage bearings prevent the rear from popping back once compressed therefore expect a rough ride.

As for the piston, that's just complete engine failure without much notice. The crank also seizes sometimes without leaving a bread trail of pending doom. So, what's in store? Is it the top end, bottom end or both? Tear down the engine to find out. Once in, take notice of other possible affected parts. When crank bearings seize sometimes the outer casing of the bearings break-free, damaging the inside of the engine case which requires replacing. As for all other bearings, consider them toast. You'll need new ones.

However, it's easy to avoid much of this.

Just perform routine maintenance. Seizing results from not following recommended maintenance intervals. Pistons seize from a bad fuel/oil mixture in 2-strokes or it's just an old dog inside a just as old cylinder in any type engine. An old piston and/or an old cylinder prevent the piston from seating properly resulting, sometimes, in the piston catching a ring.

And, remember back in the day when auto shops offered "lube, oil and filter"? Follow this mantra when it comes to your dirt bike or ATV. Regular oil changes along with cleaning and lubricating bearings decreases the chance of bearing-related parts seizing. Keep in mind, though, all parts eventually wear out so replace these worn components and don't mess with the specs just to save a few bucks.

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Written By: AndrewT