I know that oil threads are not very popular. I'm sorry. I'm just getting a feel for this bike. (ZX14R) My local motorcycle parts store has a bunch of top-end motorcycle oil on clearance. Most of it is 20w-50. Most of it is also semi-syn. Kawasaki DOES list 20W-50 as acceptable for higher heat climates but not below 32 degrees. (It sounds like Florida.) However, I don't see many posts about thicker oil. Only the 10w-40. Would 20w-50 be o.k. once the engine is broken in? I just want opinions and thank you. You guys have already been there...done that.

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A thicker oil will lower fuel mileage, and kill some power. I would stick with the oil recommended for your climate. To answer your question, you can run it, but it's not the best option for temps below 90 degrees ambient.

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Yeah. I didn't buy it yet because my brain is stuck on 10w-40. Thanks.

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I have been under the impression that oil viscosity is mainly a factor for starting the engine and warming it up to operating temp. Once any oil is hot, it's going to be pretty low in viscosity but the oil is circulating so the ability for oil to stick to parts doesn't matter much. Right or wrong?

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There is ambient temp vs. flow rate (viscosity). In the winter I want a thin flowing oil that will pass thru the channels on a cold day. So I want something like 5w30. Look at it as 5 flows fastest and is needed when cold. A 30 acts the thick weight when hot.

Fla. would be fine using a 20w50 flow rate being warm is the ambient, 50w is thick to retain the heat to carry it away. So in a way you could look at it as FLOwRetention is 5w30 or 20w50. 5 being so cold needing that flow, 30 is the retention in a cold environment so it does not work as hard or in proportion to a hotter, 50w ambient climate. That sort of make sense looking at the numbers that way?

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I have been under the impression that oil viscosity is mainly a factor for starting the engine and warming it up to operating temp.

It's more for faster movement for the dry, spinning parts can eat each other within seconds. Oil is a lube be it hot or cold, so it's more for getting the splash or pressure to begin it's lubing process.

Once any oil is hot, it's going to be pretty low in viscosity but the oil is circulating so the ability for oil to stick to parts doesn't matter much. Right or wrong?

Right on the low viscosity. You can look at that oil thru a tube as you could air thru an intake port. Flow is the center part of the rush. The walls of the tube/port cause a drag to happen, so they slowly roll over the surface at a slower rate. See how the heat is at the wall or metal, the slow moving cling-oil is peeling off as the center flowing-oil is collecting the heat as it constantly moves the flow to the oil cooler/radiator/etc.

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I bought nine quarts of Golden Spectro 10w40 dino for the first two oil changes. 100 miles and at 500 miles. And I purchased nine quarts of Golden Spectro 10w40 semi synthetic for the changes at 1,000 miles and 2,500 miles. All with Kawasaki filters. Then full synthetic for her lifetime. Every 1,500 miles. Sound like a good plan?

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Sounds excellent to me! I'm sure a lot of people will tell you can keep the full syn in there a lot longer than 1500 miles after break in.

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