All 650's Switching to Full Synthetic Oil

[Dankotaru]

So you are essentially recommending an out of grade oil that's too lower viscosity when cold (5W versus 10W), which is when most engine wear occurs?

I haven't recommended anything, but yes, a 5W will lubricate better at start-up than a 10W, which is when most engine wear occurs. This is exactly why manufacturers recommend 5W-xx or 0W-xx oils for colder climates.

Right. Remind me never to buy a second hand motor where you've owned it anywhen in the past.

Sure, OK.

BTW - A 5W30 oil is NOT thicker at 20C than a 10W30 oil (which is why the winter grades are different) you've contradicted your own posts multiple times. They are the same at operating temps (100C) though. I think you're the confused one here, unless you think SAE 5 oil is thicker than SAE 10? You need to stop comparing the winter grades with operating grades as it's illogical.

I think you've misunderstood. A 5W-30 oil is thicker at 20C than it was at operating temp (say 100C). It is also thicker at 20C than a 10W-30 is at operating temp (100C). You are correct that the 5W-30 and 10W-30 are both about the same viscosity at 100C, where they will both be somewhere in the range of 10 centistokes. So when your engine is at operating temperature, it's got nice hot oil pumping around at that viscosity of about 10cSt. But when you start your engine, the oil will be much more viscous, for either grade. My point was that even a 5W-30 will be much more viscous than 10 cSt at start-up. So, saying that it's 'too thin' and will cause higher wear rates at start-up doesn't make any sense. It's already many times thicker than the oil at its designed operating temp, and if anything, it will reduce start-up wear compared to a more viscous oil like 10W-30, because it has less resistance to flow at cold start-up.

A 5W oil at old-start (i.e. ambient temps) may get around the engine quicker because it's "thinner"; that does not mean it will lubricate "better" than a 10W (or even correctly) as for previously stated reasons it might be too thin to do the required job at that temp range.

And this is where it goes off the rails, but I think I get the issue now. Are you under the impression that it's actually better for the engine oil to be thicker at start-up than it is at operating temp? If that's the case, why run a multi-grade at all? Just put in some straight 30 weight and be done with it. But there's tons of research that refutes this idea. Multi-grade oils exist because the lighter weight oil at startup is better for engine lubrication. Just think about it a bit: if the engine is designed, from the bearing tolerances to the oil pump, to operate with an oil of about 10cSt viscosity, then why on earth would starting it up cold with thicker, slower pumping oil be better? I bet you don't start your bike cold and then romp on it right away because you think the thicker oil is somehow offering more protection for your engine. I bet you wait for the oil to warm up, like a responsible owner. But if thicker oil at startup is better, then why wait? Probably because when it's cold out, you can actually feel the loss of performance. Once it starts getting closer to that 10cSt viscosity, it starts feeling better.

See, if we could engineer a lubricant that was 10cSt at 20C, and stayed 10cSt at 100C, then we would have the holy grail of lubrication. But we can't because physics and chemistry. So, an engine oil is specified for the operating condition, where it spends 99% of its time, accepting that most wear will occur at start-up when the lubricant is well out of the design viscosity parameters. But, with a mutli-grade oil, we can at least minimize that viscosity spread, and improve the viscosity index of the lubricant, as seen in that chart I posted for the 10W-30. Sure, it gets thicker as it gets colder, but not as thick as a 30 weight when cold. And sure, it still thins out as it gets warmer, but not as much as a 10 weight when hot. That's what it means to minimize the viscosity spread, and a A 5W-30 does even better to minimize the viscosity spread, a 0W-30 even better still.

So, why does Honda recommend a 10W-30? I could venture a bunch of educated guesses, and would be happy to postulate if you're interested, but better cold-start protection certainly isn't one of those reasons.

 

[Arnie]

Very good explanations Dankotaru, thanks for all the info. Switching to 5w40 from 10w30 made huge difference in every aspect of running my bikes engine. I suppose 5w40 also being synthetic has a part in it too. It runs much smother at any temperature now.

 

[Dankotaru]

Very good explanations Dankotaru, thanks for all the info. Switching to 5w40 from 10w30 made huge difference in every aspect of running my bikes engine. I suppose 5w40 also being synthetic has a part in it too. It runs much smother at any temperature now.

No problem. I've been considering a 5W-40 myself, since I still ride in the winter, and the Castrol Racing 4T specs look good.

 

[Arnie]

Yeah, I picked it up after a lot of research. It was a tie between Castrol and a local brand (PENRITE) here in AU but finding Castrol on discount I went for it and am very happy with it. By the way, how do I change my bike type from CB650F to CB650F ABS in my profile?

Cheers

 

[Dankotaru]

Yeah, I picked it up after a lot of research. It was a tie between Castrol and a local brand (PENRITE) here in AU but finding Castrol on discount I went for it and am very happy with it. By the way, how do I change my bike type from CB650F to CB650F ABS in my profile?

Cheers

Sorry, not sure how to help you with that one, mate. If you message one of the mods, I bet they can take care of it.

 

[icajewler]

New member here. Sorry for a possibly 'reviving' a thread that (doesn't) seems settled. (Please forgive me for lack of communication skills, I'm more empirical than a robot).

This might be of help in clarifying viscosity and its importance:

https://www.lelubricants.com/wp-content/uploads/pdf/news/White%20Papers/simple_viscosity.pdf

[A very important point (in our bikes, almost as important as lubrication) is heat dissipation. Oil plays a very large role in this. Viscosity affects the thermal attributes of oil. Something to think about when considering mfg recommendations.]

Technically speaking, and this is based on the ratings of the oils themselves, even taking engine wear into account, the only circumstance permitting a noticeable difference between a 10w and 5w rating would be a cold start below the temperature rating of the 10w rated oil. Both will perform the same up to 210 C. The difference is, 5w is rated for temperatures as low as -30 C, and 10w for -18 C. That being said, if you live somewhere that never gets below -18 C, why use 5w? Any temperature above and they will perform the same. But icajewler, you say, the 5w is rated for a lower temperature which means it will be better for all cold starts even if that cold start is 30 C on a hot summer morning. To this, I reply: show me the numbers. If the numbers show that a -18 C oil isn't as good as a -30 C oil while operating above both of their ratings at startup, then, yes, you're correct. Until then, the difference is negligible and doesn't warrant the argument.

Now, I'm going to buy myself some 5w30 and do my oil change (because that's how I stumbled across this informational thread). And I'm going to rest easy knowing that there is no difference between the two oils in my climate other than the placebo effect of less wear and a better clutch. The biggest difference you will notice by far is what brand you buy anyway. The rating itself is more of a goal rather than a specification for a lot of manufacturers. Buy a good brand and you will never look back at generic. Unless you really don't care enough to notice. Then put some olive oil in it and call it a day.

Consider the white paper. Enjoy debating (please, don't take this stuff personally. You could probably run LPG straight from the refinery in modern engines and still get a good life out of them. Feeling some type of way about it is silly).

 

[Dankotaru]

New member here. Sorry for a possibly 'reviving' a thread that (doesn't) seems settled. (Please forgive me for lack of communication skills, I'm more empirical than a robot).

This might be of help in clarifying viscosity and its importance:

https://www.lelubricants.com/wp-content/uploads/pdf/news/White%20Papers/simple_viscosity.pdf

[A very important point (in our bikes, almost as important as lubrication) is heat dissipation. Oil plays a very large role in this. Viscosity affects the thermal attributes of oil. Something to think about when considering mfg recommendations.]

Technically speaking, and this is based on the ratings of the oils themselves, even taking engine wear into account, the only circumstance permitting a noticeable difference between a 10w and 5w rating would be a cold start below the temperature rating of the 10w rated oil. Both will perform the same up to 210 C. The difference is, 5w is rated for temperatures as low as -30 C, and 10w for -18 C. That being said, if you live somewhere that never gets below -18 C, why use 5w? Any temperature above and they will perform the same. But icajewler, you say, the 5w is rated for a lower temperature which means it will be better for all cold starts even if that cold start is 30 C on a hot summer morning. To this, I reply: show me the numbers. If the numbers show that a -18 C oil isn't as good as a -30 C oil while operating above both of their ratings at startup, then, yes, you're correct. Until then, the difference is negligible and doesn't warrant the argument.

Now, I'm going to buy myself some 5w30 and do my oil change (because that's how I stumbled across this informational thread). And I'm going to rest easy knowing that there is no difference between the two oils in my climate other than the placebo effect of less wear and a better clutch. The biggest difference you will notice by far is what brand you buy anyway. The rating itself is more of a goal rather than a specification for a lot of manufacturers. Buy a good brand and you will never look back at generic. Unless you really don't care enough to notice. Then put some olive oil in it and call it a day.

Consider the white paper. Enjoy debating (please, don't take this stuff personally. You could probably run LPG straight from the refinery in modern engines and still get a good life out of them. Feeling some type of way about it is silly).

Good article from LE. And you're right about thermal considerations.

I think your understanding of viscosity and the W weights is a little off. Depending on the VI and actual viscosity measures of the oil, a 5W-30 will flow easier (and thereby reduce start-up wear) than a 10W-30 at most temperatures, not only at -18C. This can be evaluated pretty easily with any number of viscosity calculators, as long as you know the oil specs you want to compare. There are a number of SAE white papers establishing this benefit, such as a 0W oil pressurizing the system (critical for main and rod bearing hydrodynamic lubrication) up to 30% faster than a 10W during cold starts. As the starting temps increase, there is a point at which pressurization time normalizes and only pumping losses are reduced, but it varies according to the engine and pump parameters.

 

[icajewler]

I think your understanding of viscosity and the W weights is a little off.

It is my understanding that the W rating pertains to use at the limits of operation, specifically freezing temperatures (W = winter rating).

Depending on the VI and actual viscosity measures of the oil, a 5W-30 will flow easier (and thereby reduce start-up wear) than a 10W-30 at most temperatures, not only at -18C.

The point I wanted to make was that this difference in 'flow' is negligible in regard to engine wear over the life of the engine. If it were monetarily significant, the status quo would reveal it to be so.

As the starting temps increase, there is a point at which pressurization time normalizes and only pumping losses are reduced, but it varies according to the engine and pump parameters.

This is the thin line that this debate relies on. At what temperature do the two ratings become essentially the same oil? My claim is that for the large majority of climates where people are most likely to ride a motorcycle (not at -18 C), there isn't a difference.

Cheers

 

[Dankotaru]

It is my understanding that the W rating pertains to use at the limits of operation, specifically freezing temperatures (W = winter rating).

Yeah, the "W" rating is determined by viscosity at a specific temperature, centipoise at -25 for a 10W, -35 for a 0W, etc... but even for two 30 weights (0W-30 and 10W-30, for example) the viscosity remains different across the temperature range, and will likely achieve the same viscosity at a given temperature near operating temps (100C). Depending on the grade and VI, that point may be a little lower than 100C, and some might have that point at a much higher temp, or not even ever share the same viscosity at all before 150C (HTHS, so no one measures or cares at temps higher than that).

The point I wanted to make was that this difference in 'flow' is negligible in regard to engine wear over the life of the engine. If it were monetarily significant, the status quo would reveal it to be so.

This is the thin line that this debate relies on. At what temperature do the two ratings become essentially the same oil? My claim is that for the large majority of climates where people are most likely to ride a motorcycle (not at -18 C), there isn't a difference.

Cheers

I go with the well-established principal that any improvement in viscosity at cold start is beneficial. Besides, oils with higher VI and lower viscosity at start-up not only pressurize faster, they reach operating temp faster, which is also important for the performance of many additives (zinc and phosphorus additives, like ZDDP for example, don't chemically etch ferrous surfaces until they reach temp).

I agree that at most temps people ride a motorcycle, it likely isn't a big enough difference. I calculated it out in another post, but comparing a 5W-30 Motul to a 10W-30 Motul, the 5W-30 is 200cSt at 14C (57F), while the 10W-30 is about 280 cSt at the same temp (about 40% thicker). That difference between them isn't huge considering how much thicker both oils are at 14C compared to their operating temp, but it's noticeable in pumping resistance and it only gets more important as the temperature decreases and the viscosity difference between them increases exponentially. But at what temp will a 5W-xx make a noticeable impact at start-up over a 10W-xx on your bike? Who knows. But again, any improvement in cold start viscosity is always an improvement. If you ride in cold temps, a 5W-30 or 40 will flow easier and only make life better for your motorcycle during and after cold starts.

Cheers!

 

[Brammers]

The official recommendation of this forum is 10w30 or 10w40 as recommended by Honda.

Anything else is seen as an experiment which may invalidate your warranty, although on a 2014 bike that isn't a massive concern.

Good luck!

 

[cb650ftw]

Has anyone on here used Motul 7100 10w-30 in their bikes ?

 

[Cláudio Nogueira]

Well, viscosity change is also for better. Lower limit 5 rated oil remains thinner consequently flows much better when cold compared to 10 and Higher limit 40 rated oil remains thicker consequently protects much better than 30 rated oil when hot. 30 rated oil is recommended where outside temperature does not exceed 25-30 degrees C , here in Sydney it is always above 30 in summer and we have plenty of days above 40 sometimes even above 45, recorded 50 on a few days last year. Honda also states to use 10w30 or higher spec oil. Yeah it doesn't get that cold here to warrant using 5 lower spec oil but I can't find the oil I used in 10 lower spec and 5 provides much better protection when cold especially during start up when cold. Any Internal Combustion Engine sustains the most damage (wear & tear) during cold start ups until reaching optimal running temperature. There is nothing wrong with using higher spec oil on contrary it is correct due to the reasons I mentioned above. It doesn't hurt anything other than your wallet but in the wide spectrum of expenses for a motorbike, what's $30-40 difference for an oil change not to mention the filter. Some people change oil but not the filter, I can never get my head around this.

I think you are confusing "higher spec" with "higher viscosity"! Here in south Portugal is frequent to have near 40ºC in summer and Honda still recommends 10W30. That´s what "everybody" is using here on these bikes.
Outside temperature is not the only factor influencing the recommendation. More important is the engine conception and the tightness of its components. You need the best viscosity range that suits a normal range of outside temperatures. It´s not a good practice to do different from what manufacture recommends regarding viscosity. Otherwise Honda would have placed a temperature related chart on the manual for us to choose dependent on the outside temperature.
Better oil spec yes, change viscisity, NO.

 

[Brammers]

Ambient temperature is almost irrelevant on engine oil, once the engine is up to operating temperature.

This is because the cooling system keeps the engine at a set temp (which is around 100C/212F) regardless of air temp - so the oil is always operating in a known environment.

The 10W part (cold weight) is different, but also linked to tolerances more than ambient conditions. If things are so cold that you might need to drop to a 0W30 oil, you should reconsider whether to ride or not!

J

 

[motorider]

Hi everyone,

A new owner from down under (Australia) of 2019 CB650F.

View attachment 6616


After the first service was done by the dealer @ 1200 kms last January, I replaced the oil with Castrol Power 1 Racing 5W40 full synthetic @ 4750 kms yesterday.
The oil put in there by the dealer must be cheapest oil they could get their hands on because the difference is like night and day. The engine runs much smoother both when cold and hot and it is even quieter. I regret that I didn't change it sooner. Not to mention the clutch, it grabs much much smoother and gear changes are like dream.

Cheers

Arnie

Fully synthetic oil is great as long as it is formulated for motorcycles and within the viscosity range specified in the owner’s manual. I use 10W-30 fully synthetic Honda Pro HP4S. Using 5W-40 should be fine, it just means the oil will be thinner when it’s cold which means less lubrication on start up. It’s only really necessary to use 5W in extremely cold climates. But if that’s all you can get then it will work just fine.

 

[Cláudio Nogueira]

Fully synthetic oil is great as long as it is formulated for motorcycles and within the viscosity range specified in the owner’s manual. I use 10W-30 fully synthetic Honda Pro HP4S. Using 5W-40 should be fine, it just means the oil will be thinner when it’s cold which means less lubrication on start up. It’s only really necessary to use 5W in extremely cold climates. But if that’s all you can get then it will work just fine.

I believe most of our machines are kept inside doors, so, they will not be submitted to real cold starts. Once they warm up and go outside, this cold start oil viscosity is irrelevant. Its takes only 2 minutes for this to become irrelevant, the time you need to put your helmet and winter gloves on.
As Brammers stated, If you make such a cold start that justifies a 0 or 5W oil on a CB650, I would reconsider if I would go out on the bike ;-) 10W30 will cover it all.

I believe, there's a reason why Honda recommends 10W30, so we, users don´t need to spend time making engineering guess... like I'm doing now ;-)
This fellow needs a 5W-something... and a hot cup of tea ;-)

 

[Dankotaru]

I think you are confusing "higher spec" with "higher viscosity"!

I understand what you're saying, but he's not wrong. There are several specifications that will always be better with a 5W-40 compared to a 10W-30, like the Viscosity Index, HTHS, JASO shear stability, etc...

Here in south Portugal is frequent to have near 40ºC in summer and Honda still recommends 10W30. That´s what "everybody" is using here on these bikes.

Beautiful country, I would love to visit one day. In the climates and conditions most people ride, a 10W-30 is perfectly fine and what's recommended, but there are better options within that viscosity range for those who want better flow on cold start-up or want to prevent it thinning out too much in hotter environments like track duty.

Outside temperature is not the only factor influencing the recommendation. More important is the engine conception and the tightness of its components. You need the best viscosity range that suits a normal range of outside temperatures. It´s not a good practice to do different from what manufacture recommends regarding viscosity. Otherwise Honda would have placed a temperature related chart on the manual for us to choose dependent on the outside temperature.
Better oil spec yes, change viscisity, NO.

The viscosity range of a 10W-30 is relatively wide. A 5W-40 has a much narrower viscosity range that never exceeds the cold or hot viscosity parameters of the 10W-30. In other words, the 5W-40 is not nearly as thick as the 10W-30 when cold started and not quite as thin as the 10W-30 when hot, and because it's closer to the operating (hot) viscosity when started, it will heat up and reach that operating viscosity faster than the 10W-30, which makes it more consistent for lubrication. The consideration for clearances has more to do with not selecting an oil that is outside the designed operating viscosity, like going to a 15W-xx oil or a xW-20 oil.

 

[Dankotaru]

View attachment 11694

I definitely have gone to work on winter mornings and felt as though I looked liked this by the time I arrived.

 

[Dankotaru]

Ambient temperature is almost irrelevant on engine oil, once the engine is up to operating temperature.

You're right, most of the time your engine oil is spent in a fairly temperature controlled environment regardless of the ambient conditions. But that's why the ambient temperature is so important, because on start-up the oil is not yet in that controlled environment where it's pumped around nice and hot and thin. The oil at start-up is colder and much thicker than its operating viscosity, and the ambient conditions will determine just how much thicker the oil is than it will be once it's finally at operating temp. The colder it is, the thicker the oil at start-up. And that thick oil doesn't flow as well, so it takes time to pressurize and provide lubrication. This is why most engine wear occurs at start-up, and precisely why we use multi-grade oils to improve cold-start lubrication.

This is because the cooling system keeps the engine at a set temp (which is around 100C/212F) regardless of air temp - so the oil is always operating in a known environment.

The 10W part (cold weight) is different, but also linked to tolerances more than ambient conditions. If things are so cold that you might need to drop to a 0W30 oil, you should reconsider whether to ride or not!

J

Ambient conditions is the primary driver for the cold (winter) weight of multi-weight oils, not clearances (you said tolerances, but I know what you meant). Especially when discussing a 10W-30, which has a relatively wide viscosity range from cold to hot, it's the opposite of an oil that maintains consistent viscosity for clearances.

While the operating conditions for most riders won't ever necessitate anything other than a 10W-30, the ambient temps don't have to be as cold as you might think to see a difference in cold-start lubrication between a 10W-30, 5W-30, and 0W-30. It varies by engine design, but when the SAE and ASTM assessed the relationship of cold start lubrication to engine oil viscosity J300 specs using 'newer' DOHC engine designs in the mid-90s (the previous study was done in the 70s), most of the engines saw differences in pressurization time between those grades starting above freezing temperatures. Around freezing seems to be where start-up lubrication begins to suffer on my bike using the HP4S and I get a few extra seconds of clatter before it pressurizes. A 5W-40 improves cold start lubrication at these temps. It's also not terribly difficult to get an engine oil consistently operating above 100C, despite the cooling system's best efforts. This is why a lot folks run a higher weight at the track. A 5W-40 at 235F can be the same viscosity as a10W-30 at 210F.

edit: as a follow-up, here's an article about the future of older, 'lower performance' oil grades like 10W-30 in particular. To quote from the article, "In any event, the blenders have a difficult choice to make: Do I degrade my synthetic, high-performing product in order to meet viscometric requirements, or do I abandon the traditional SAE 10W-30 viscosity grade?" Steve also discusses the history of the J300 specification in detail. Some might find it interesting: https://www.lubesngreases.com/magazine/26_01/automotive-183/

 

[JDude]

A little off topic, I have a magnetic oil pan heater that I’ve used on various vehicles. If I feel the need to start the bike when it’s -30 C it’s makes for a very quick start. Not that I’m going for a ride in the snow. My Honda Odyssey hates the cold!

 

[Blav]

I wanted to use something better. The manual says 10w30 or better grade. So I looked for a better oil. After an extensive search decided on Castrol Power 1 Racing 5W40 full synthetic and am extremely happy with it. If the oil used by the dealer during the first service is recommended oil, I wouldn't touch it with a 6 foot stick.

Hi, first, congratz for your new CB650F almost brain new 👍, hope you'll enjoy the ride especially in high rpm. Like you, I'm using too a full synthetic better than the recommended one, a bit expensive but i see a difference in the sound and in the power, it's like it's breathing a way better. You did well by upgradting your oil.