Moto Myths Exposed: Motorcycle Oils
Oil is Oil, right?
     "Oil is on sale at XYZ Auto, let's stock up! Oil is oil, right?" Well, maybe. It all comes from the ground, but modern oils are built with synthetic additives to address specific operating conditions. The current API standard is oil specification SJ. This indicates how well the oil will hold pressure in plain bearings, lubricate piston skirts, disperse heat and sludge, and resist corrosion. Your motorcycle engine needs all this, but unlike a car the engine oil also lubricates the transmission and clutch.
     The meshing action of the transmission gears will actually rip the oil molecules apart unless extreme pressure additives are also used. EP (Hypoid) additives will allow smoother shifting and minimize oil breakdown. SJ oils cannot have these additives. The older SH standard can. Do not use SJ oils.
     Motorcycle oils, tailored to motorcycle power plants, offer consistent lubrication much longer than automotive oils. Your engine will be generally quieter, shift better, and components such as clutches and alternators, which are lubed and cooled by oil, will last far longer.

Why motorcycle oil costs more
     Motorcycles have special lubrication needs. Your engine oil must also lubricate your transmission, requiring extreme pressure additives for the gears. Motorcycle oils cost more than automotive oil, but the benefits are smoother shifting and a quiet, long lasting motor.
     Two cycle motorcycle oils are formulated for the specific demands of a motorcycle engine. Outboard and chain saw oils are designed differently and oils for them are inadequate in your motorcycle. Using motorcycle specific oil will greatly extend the life of your motorcycle.

Friction reducers
Dear Dr. Spoke,
     Which friction reducer should I add to my oil? Is molecular bonding better than Teflon, or should the oil be more slippery?

Dear Slick,
     Most of these products work to some degree, but the catch is expense. Modern motorcycle engine designs use oil pressure to eliminate metal-to-metal contact. Only at start-up or extreme racing load will there be significant wear. Any coating on the metal will seldom be utilized. Cycle oils have additives to protect at start-up or racing. Adding other chemicals can upset chemical balance of the oil and lessen its ability to protect under pressure.
     Transmissions require an extreme pressure additive or the meshing gears will rip the oil apart. Any product without the E.P. additives will be broken down to uselessness within a few hundred miles.
     Your clutch depends on friction to work. It is also bathed with the same oil, lubricating your engine and transmission. Most clutch problems start with springs worn out from the heat of clutch usage. A friction reducer of any type will cause slippage. Slippage will generate excess heat to wear out springs faster. Some products claim 'safe for clutches'.
     I have never seen long term success with any additive in any motorcycle engine. All you really need is a good motorcycle oil to protect your engine.
Dr. Spoke

Checking your oil
     Motorcycles are sensitive to oil levels. Check your oil with the motorcycle on the center stand or hold it upright off the side stand. Wait five minutes before checking.
     Dipsticks should not be screwed in to check, just rested on the case.
     Many motorcycles have a sight level to be visible between the marks stamped next to the window.
     Add only three or four ounces at a time. It won't take a full quart.
     A few ounces low can cause engine damage when the oil pump starves under acceleration.
     A few ounces high can cause excess crankcase pressure and pump oil into the air cleaner and carburetors, and cause oil leaks.

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Moto Myths Exposed: Breaking in a new engine
      Recently, I was referred to a web site touting a hard and fast break-in, get more power, longer life, less blow-by, and win races!

     This is a variation on the myth "Break it in like you are going to ride it".

     NEWS FLASH - Engines are not horses, people, or any kind of living thing. They are lumps of metal that respond to sound engineering principles. Psychology DOES NOT work.

     Every manufacturer of every motor vehicle recommends essentially the same break-in procedure. If you truly believe that you know more than all the engineers in the world combined, then do it your way.

     The rest of you can read your owner's manuals. Go the specified speeds for the specified time and mileage, and change the oil on time. Your reward will be a great running, trouble-free, and long lived engine with the warranty still in effect.

     The purpose of break-in is to finish the polishing and fitting of parts that is too expensive to complete in the factory. No matter how well finished an engine is, it will always benefit from a careful break-in.

     Here's how it works: examine any piece of metal under a microscope. It will look like a moonscape with mountains and valleys. Now, polish until your power buffer burns out. It will STILL look essentially the same, Just smaller.

     Break-in heats up the parts so expansion will bring the tops of the mountains to just barely contact the mountain peaks on a facing piece (i.e. Piston to cylinder). The tips will wear down (polish) a little. Then, if you let everything cool, you can repeat the cycle until you have two perfectly mating parts.

     Rush the break-in and those mountain peaks tend to break off instead of polishing. Now you have chunks of metal floating around, getting stuck between other moving parts.

     There will always be anecdotal evidence of "a better way". But what worked for your friend's 2nd step cousin probably didn't work as well as he thinks, and will take a huge lucky break to work for you.

     The bottom line is: you won't go wrong by reading the book and following the instructions.

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