Winter Oil

[edscoot]

Has anybody/everybody swapped over to 10w30 from 10w40 for the colder weather yet? I can't find 30 locally and wondered about just continuing using 10w40. Maybe I can't find any 30 because every mb and scoot rider has bought all the stock

[edscoot]

Got some 10w30 at lunchtime.

[maddiedog]

I've been using 10w40, I just make sure to let the bike warm up some to get that oil flowing before I ride.

In the owners manual that comes with the bike on, page 94 shows both 10w-30 and 10w-40 in the same arrow, meaning both are appropriate for the entire temperature range of the bike. If there were two arrows, each type would only apply to a certain range.

For reference, here's the page I'm referring to...

Untitled.png (117.59 KiB) Viewed 3192 times

And if you lost your manual, I attached a scanned version. Since it comes with the bike for free, I don't think uploading it here hurts anyone (and if it does, please PM me and I'll remove this immediately). Here's a direct link to the manual:

HondaPCXManual.pdf

(2.05 MiB) Downloaded 176 times

[edscoot]

Well I've got some 10w30 now so I may as well use it. I change the oil half way between services so the engine'll have 10w40 back in in 1250ml or so.

Fingers crossed we won't be getting temps lower than -10 this winter but we have for the last two - I wonder what oil you would use then. I'm pretty sure I'd take the car in those conditions.

[Fiah]

10w30 vs 10w40 won't make a big difference, Honda recommends 10w30 anyway for temperate weather

0w30, that would make a real difference

my dealer thought it would be a brilliant idea to put 10w40 in right before the winter

[maddiedog]

Wow, why would they do that? That's a dumb thing to do. Dealers will be dealers...

[Fiah]

Wow, why would they do that? That's a dumb thing to do. Dealers will be dealers...

My guess is that they just throw 10w40 in anything that they touch.

[gn2]

Mine has the slidey oil in it.
Works a treat.

[edscoot]

I've just being trawling through the net for more info on this and I've come to the conclusion that what you do is put the oil in that honda recommends and forget about it

As maddiedog says just let your engine run a bit before setting off to allow the oil to get around the engine - I do this anyway by starting the engine before putting my gloves etc. on and then take it easy for the first few minutes of riding. I do this with the car as well.

I suppose in really cold weather you may need to give the engine more time to heat up, but if it's much below 0deg I don't fancy riding anyway.

I'm not sure what putting 0w30 in would do to your warranty.

[Fiah]

I'm not sure what putting 0w30 in would do to your warranty.

Well, assuming 10w30 is a correct oil to use and would not void warranty, there is no reason why 0w30 would void warranty. The reason being that the viscosity of both oils at operating temperature is the same (30 weight). The viscosity of the 0w30 oil when it's cold is like a 0 weight oil, while the viscosity of the cold 10w30 oil is like 10 weight oil. That is how the oil naming scheme works. Note that when cold, both oils are thicker than they are when hot.

What that means for us is that at operating temperature, the oils are one and the same. However, as long as the oil is still warming up, the 0w30 oil will flow better than the 10w30 oil, because its viscosity is lower.

I don't see how 0w30 oil could ever be worse than 10w30 oil for this application!

[edscoot]

I understand about the 0w 5w 10w etc. weight thing.

I wonder why 0w X isn't the recommended oil for all engines? It would seem to be a very obvious way to reduce engine wear - or perhaps I've just answered my own question - there's more money to be made with more engine wear.

[gn2]

Running a lubricant that's too thin can do just as much damage as one that's too thick.
READ THE MANUAL AND STICK TO WHAT IT SAYS!!!!!

[edscoot]

Running a lubricant that's too thin can do just as much damage as one that's too thick.
READ THE MANUAL AND STICK TO WHAT IT SAYS!!!!!

Agreed, that's what I'm doing and I'm sure what most people will be doing.

[Fiah]

Running a lubricant that's too thin can do just as much damage as one that's too thick.
READ THE MANUAL AND STICK TO WHAT IT SAYS!!!!!

How is 0w thinner than 10w? It's only less thick when it's cold. Running a 0w20 oil would most likely damage the engine, yes, because it would thin out too much at operating temperature.

[Fiah]

I understand about the 0w 5w 10w etc. weight thing.

I wonder why 0w X isn't the recommended oil for all engines? It would seem to be a very obvious way to reduce engine wear - or perhaps I've just answered my own question - there's more money to be made with more engine wear.

The reason is that it's not necessary, and 0w oils are more expensive.

[maddiedog]

Less thick is the same as thinner...

When the engine is cold, you need a certain amount of sticky lubrication to keep the surfaces coated. The oil is dual-weight for this purpose -- until the surfaces heat, everything needs extra lubrication, hence the thicker initial weight.

When you first start the bike, the 0w oil might cause damage due to insufficient lubrication compared to the 10w... Especially if you ride it before the engine is warm...

[trigg123]

opie oils .co uk

[Fiah]

Less thick is the same as thinner...

When the engine is cold, you need a certain amount of sticky lubrication to keep the surfaces coated. The oil is dual-weight for this purpose -- until the surfaces heat, everything needs extra lubrication, hence the thicker initial weight.

When you first start the bike, the 0w oil might cause damage due to insufficient lubrication compared to the 10w... Especially if you ride it before the engine is warm...

Thicker compared to what? Cold 0W40 oil is a lot thicker than a hot 10W40 oil. Cold 10W40 is a lot thicker than hot 0W40 oil. Cold 0W40 oil is somewhat thinner than cold 10W40 oil. Are you saying that a cold engine needs thick oil to prevent wear? Why not go with 15W40 then?

You should read up on multi-grade oil: http://en.wikipedia.org/wiki/Motor_oil#Multi-grade

[maddiedog]

I understand oil weight completely, I think you misread my post. There is no relativity coming into play here, I am talking about which oil will be thicker at initial startup, when the engine is room temperature or below.

Clearly cold 0w40 is thinner than 10w40 at startup, when the engine is cold. What I was suggesting is, 0w weight is not used at startup because it does not provide as much initial lubrication as a thicker oil.

0w oil is very thin at startup. 10w is also thin, but not quite as thin. If the oil is too thin, a film of oil won't stay on the cylinder walls, causing the piston rings to rub down the cylinder. Or, oil may pass the piston rings and burn. Alternatively, you don't want to use too thick oil, because it will put additional strain on the engine at cold, and won't flow over all the engine components as easily.

We're being facetious here though. Honestly, the engine would probably be fine with either -- especially if you let it warm up before cranking the throttle (the oils will be the same once they warm up). I just have a strong opinion on the matter because I know that Honda won't intentionally design an engine to fail or wear down.

READ THE MANUAL AND STICK TO WHAT IT SAYS!!!!!

[Fiah]

I understand oil weight completely, I think you misread my post. There is no relativity coming into play here, I am talking about which oil will be thicker at initial startup, when the engine is room temperature or below.

Clearly cold 0w40 is thinner than 10w40 at startup, when the engine is cold. What I was suggesting is, 0w weight is not used at startup because it does not provide as much initial lubrication as a thicker oil.

0w oil is very thin at startup. 10w is also thin, but not quite as thin. If the oil is too thin, a film of oil won't stay on the cylinder walls, causing the piston rings to rub down the cylinder. Or, oil may pass the piston rings and burn. Alternatively, you don't want to use too thick oil, because it will put additional strain on the engine at cold, and won't flow over all the engine components as easily.

We're being facetious here though. Honestly, the engine would probably be fine with either -- especially if you let it warm up before cranking the throttle (the oils will be the same once they warm up). I just have a strong opinion on the matter because I know that Honda won't intentionally design an engine to fail or wear down.

READ THE MANUAL AND STICK TO WHAT IT SAYS!!!!!

I hear what you are saying, but I must object to what you are implying here: "0w oil is very thin at startup. 10w is also thin, but not quite as thin."

Quite simply: 0W oil is not very thin at startup at all! Yes, it's pretty much thinner than any other oil would be at that temperature, but a cold 0W oil is still several orders of magnitude thicker than warm oil. If a cold 0W oil would pass the piston rings and burn, a warm oil would most definitely pass the rings and burn in a giant blue cloud of smoke. If a cold 0W oil was too thin to form a film, any warm oil would form no film at all and lubricate about as well as a bucket of water.

I've been looking for a graph that nicely illustrates my point and found it hard to find a good one, but this one should suffice:



Keep in mind that the vertical scale is logarithmic! To clarify my point (the graph is horrible to read IMHO), I colored the lines for straight 30 and 10 weight oils red, and 10W30 oil in blue:



As this graph will tell you, cold oil is always thicker than warm oil, but 10W30 is less thick when cold than 'normal' 30 weight oil. 0W30 goes just a little bit further.

My reasoning for using 0W oil over any 5W, 10W or 15W oil is that a 0W oil will reach critical parts of the engine a lot sooner than the others at a cold start. And cold start is where most of the engine wear occurs, because many parts are essentially dry when you first crank the engine, due to the (warm and thin!) oil sinking to the sump the last time it ran. That Honda says that you need 10W30 is not because 10W30 is the only right oil, but bcause it is sufficient. You don't need 5W30 or 0W30, as 10W30 is thin enough at normal temperatures that the engine will turn over just fine.