1. Welcome to Bike Talk, a forum for all bikers and motorcycle enthusiasts. If you are new to Bike Talk, be sure to register for free and join the conversation.

    There's always someone around willing to help out with questions or give a friendly wave back. All Harley and metric riders are welcome.

Amsoil 75-140 SVO Oil

Discussion in 'Pull up a chair and sit for a spell' started by cardboard, Apr 21, 2008.

  1. Art_NJr

    Art_NJr New Member

    Mar 16, 2008
    Likes Received:
    North Carolina
    As long as it's got the additives for a "wet clutch" you'll be fine.

    Also, to make lubricant with a really wide range, like 75-140, you have to use a LOT of additives. The theory is that the gear oil acts like a 75 cold but a 140 hot & to do that you start with a 75 & put in a lot of additives to make it "act" like a 140 hot. Oil (conventional or synthetic) doesn't "wear out" but the additives sure do & heat breaks 'em down quick.

    A chemical engineer I worked for explained it like this - the molecular structure is like a licorice stick or a DNA molecule - twisted. As the oil heats up, those additive molecules start to unwind & get longer - they'll twist back tighter & get shorter as the oil cools down. But if the oil gets too hot, the molecular structure just falls apart & you can't put it back together again.

    And the more additives you use, the less time the oil will last. That's true with anything - engine oil, primary fluid, trans fluid, whatever. Lots of gimmicky stuff on the market & lots of fancy lab tests to make you think it's the greatest thing since sliced bread. But as I said, when you take the engine, transmission, whatever apart & measure the parts with a micrometer, you'll soon see what works & what doesn't.

Share This Page