20-50

[zx6r_aj]

soo i live in fl and a bunch of people run thicker oil? 20-50,why is that?is it better?

[Hammerhead]

Only way I would run 20-50 is if my motor had a zillion miles on it and was a clapped-out, rattling piece of junk that needed thick oil to keep the deafening roar of the pistons slapping from setting off car alarms. The first number in a multi-weight oil is the flow viscosity and the second is the film strength at operating temperature. The 20 is twice as thick as the 10 and therefore makes the oil pump work twice as hard to supply wear surfaces in the motor while only adding 10 points of film strength. 20-50 will not help your motor last longer and it definitely won't make it run better, in fact the opposite is true; thicker oil is a horsepower drain.

[rexmitchell]

20w50 would be good if you were running it on a track bike at high temperatures without a lot of start ups....stick with 10w40

[zx6r_aj]

i mean...its summer time?the bikes get soo hott riding around ripping on them..i thought it be best having thicker oil during the summer..

[JKL1960]

Originally Posted by Hammerhead

Only way I would run 20-50 is if my motor had a zillion miles on it and was a clapped-out, rattling piece of junk that needed thick oil to keep the deafening roar of the pistons slapping from setting off car alarms. The first number in a multi-weight oil is the flow viscosity and the second is the film strength at operating temperature. The 20 is twice as thick as the 10 and therefore makes the oil pump work twice as hard to supply wear surfaces in the motor while only adding 10 points of film strength. 20-50 will not help your motor last longer and it definitely won't make it run better, in fact the opposite is true; thicker oil is a horsepower drain.

[Hammerhead]

Originally Posted by zx6r_aj

i mean...its summer time?the bikes get soo hott riding around ripping on them..i thought it be best having thicker oil during the summer..

Your motor wouold be better served by changing to a high-performance coolant such as Engine Ice and perhaps adding a manual fan switch. Thicker oil can increase friction and windage (the drag on moving parts as they sling oil around) and possibly make a motor run hotter due to the fact that the thinner oil circulates easier and carries more heat to be sloughed off by the oil cooler. Stick with what the manufacturer recommends.

[villian88]

Are you guys really this clueless? I hate to get on here sounding like a dick, but there's a reason every manual, every service book, and every motorcycle tech will tell you to use 10-40 up untill 100 degrees F (outside temp), and 20-50 after that. To the original poster: Use 20-50 if you are going to be riding in any temp. aproaching or passing 100* outdoors.

10-40 and 20-50 are MULTIWEIGHT...you nimrods. That means, that 10-40 and 20-50 SHARE the same weight between 20-40, but allow for 10-40 to be lighter below that (in cold weather, like winter) and 20-50 to get heavier in hot weather (summer). Therefore, 20-50 is NOT heavier than 10-40 the majority of the time, its exactly the same...untill you reach 100*F outside. Then it can exceed 40w and become anything up untill 50w, it won't exceed 50w. That is good, it protects the oil from breakdown and keeps your engine from...blowing up...for all intensive purposes. Each oil is the EXACT same weight at any given time, untill its super cold, or super hot.

[Morgan]

You seem awfully sure of yourself, so could you tell me at what point the 40 starts to get exceeded? Other than "super hot"? And can you please tell me when when 20 is exceeded on the low side, other than "super cold" or "wintertime"? IE, what temperatures? Because I don't know any techs in DALLAS TX (where it gets hot on occasion) who tell people they need to run 20w50 in the summer in a liquid cooled bike. I could see 10w50 if you could find it... My 01 ZX11 manual says to use 10w40, 10w50, 20w40 or 20w50, but gives no guideline as to when. But I don't see the 20 being necessary ever. But since you know so much, I'd sure like to know specifically when the 20 gets exceeded on the low side.

My Honda VTX manual says use 10w40 period.

And interestingly, my Honda engined Saturn Vue say the only oil weight to use is 5w20. I've been using that and the engine runs just fine, no overheating issues.

Look up the words "acerbic" and "ad hominem attack" and try to avoid that in the future. Just friendly advice, that.

[Hammerhead]

If you don't want to sound like a dick, stop acting like one. Have you read the service manual for every bike ever made? Mine certainly doesn't say to use 20-50 anywhere. Those reccomendations were mostly for air-cooled motors.

[Morgan]

You see, the reason you don't run 50 in your liquid cooled engine is that your cooling system doesn't allow your engine to GET to "super hot." And the 10 weight IS faster flowing on startup at ambient temperature.

[villian88]

Originally Posted by Morgan

And the 10 weight IS faster flowing on startup at ambient temperature.

I wasn't arguing that...was I? In fact, I haven't said anything about oil on the low side, at its startup weight...which...if you want to get super picky isn't nessecarily the lowest number mentioned on the bottle. Its all relative to temp., and at...lets say...70*f ambient, a 20w50 oil is the exact same weight as a 10w40 oil, which, for simplicity's sake lets say is 30w. All that I am trying to say, is that during uber hot days, as you experience in Dallas, an oil with a weight of 20w50 will offer much more protection and resistance to breakdown than a 10w40 oil, at high temps. 10w40 is 10w in cold, freezing, temps. 20w50 is 20w in cold, freezing, temps. Between 40-100*f they are going to be the exact same weights, at any given moment. Only after 100*f ambient will you see any difference in weights (Viscosity), and how well the oil holds up.

Why chance oil breakdown on super hot summer days, using a 10w40 oil, when a 20w50 oil gives you all the same benefits, with none of the drawbacks? To me its a no-brainer, but I guess for some people its hard to understand that 10w40 and 20w50 are exactly the same (during summer riding) untill you reach a point where you Need the oils weight to exceed 40 & prevent excessive breakdown.

[Morgan]

Uh... YEAH, you WERE arguing about the point you asked me if you were arguing about. But since you said it that way, I guess you're not disputing the fact that 20w oil is slower flowing at startup, right?

And 20w50 oil doesn't protect any better IN A LIQUID COOLED ENGINE than 10w40 because the bike's thermostat doesn't allow the engine's internal temp to get that high. The ambient temp of 80 or 90 or 105 is somewhat irrelevant because the engine's internal temp is WAY higher. The ambient temp affects the cooling system's efficiency. (Edit: And yeah, if your cooling system were to die, having the 50 weight oil would keep your engine for overheating a little while longer, no doubt about it. But pushing the 20 weight thru it to start every time in the unlikely instance that your cooling system stops working and you just keep running and not caring about the heat isn't a good trade off)

20w50 is great in an air cooled harley because they engine tolerances aren't as high so the slower flow on startup doesn't cause issues, and they don't have a thermostat to keep their temp down so they DO get hot enough for the 50 weight to be important.

But like I said, I could see 10w50 being no problem, if not unnecessary overkill.

[jorgecuatro]

ill believe the Amsoil rep before anyone else.

[Morgan]

Originally Posted by jorgecuatro

ill believe the Amsoil rep before anyone else.

On behalf of sales reps the world over, let me thank you.

[Kawi_T]

Originally Posted by Morgan

20w50 is great in an air cooled harley because they engine tolerances aren't as high so the slower flow on startup doesn't cause issues, and they don't have a thermostat to keep their temp down so they DO get hot enough for the 50 weight to be important.

Did my air cooled Z just get compared to a Harley? Oh the shame ...

[villian88]

Originally Posted by Morgan

...I guess you're not disputing the fact that 20w oil is slower flowing at startup, right?

Right...if you live in Alaska. The point I'm trying to get across, is that both oil are MULTI-Weight, and are the exact same weight 99.9% of the time. Go see my 30w example in the previous post.

[zx6r_aj]

i been running 20-50 in my bike for couple weeks,,no prob does not break down as fast..i think most bikes in fl that race,stunt,or just hall ass uses it also

[Hammerhead]

Everyone is free to dump whatever red dog swill in their sumps they want, just get back to me whenever you turn over 100K with nothing other than gas, tires, oil and maintenance.

[rybetz42]

I have a 1995 zx7 and my manual calls for 20w-40 or 20w-50 so it all depends on the bike.....

[golden city ninja]

my turn to sound like a dick. "20w50 and 10w40 and the exact same." i call shunanigans. the reason there is two different viscosities is that oil viscosities dont mix. the 10 or 20w will stay seperated from the 40 or 50w. they will not mix to make a 30w oil. do your research