All 650's Switching to Full Synthetic Oil

[Arnie]

Hi everyone,

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




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

 

[Brammers]

Hi. Any reason why you didn't use a recommended grade of oil? 10w30 or 10w40?

J

 

[Devilsfan]

Welcome to the forum!

 

[Arnie]

Hi. Any reason why you didn't use a recommended grade of oil? 10w30 or 10w40?

J

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.

 

[Arnie]

Welcome to the forum!

Thanks.

 

[Arnie]

Hi. Any reason why you didn't use a recommended grade of oil? 10w30 or 10w40?

J

What is TBR Tarmac system, what does it improve? How much power did you gain with the custom map? Is the suspension softer or stiffer after the modifications. With some of the awful roads we have down here, the original suspension is bit harsh to my taste. I did set the rear suspension to its softest setting, still harsh.

 

[Brammers]

Hi,

It's an exhaust: http://www.twobros.com

Gained about 10bhp, give or take. Suspension is a little firmer, but much more confidence inspiring.

J

 

[baugustine]

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.

Not to speak for @Brammers , but I think the question he was asking (and me too) is why did you switch from the recommended 10W-30 to 5W-40? An upgrade to full synthetic is very understandable, changing viscosity is not. There is a big difference in flow characteristics in those two, especially if your temperature dips below 40 deg F or climbs above 80 def F.

 

[Brammers]

@baugustine nailed it. Thanks!

 

[Arnie]

Not to speak for @Brammers , but I think the question he was asking (and me too) is why did you switch from the recommended 10W-30 to 5W-40? An upgrade to full synthetic is very understandable, changing viscosity is not. There is a big difference in flow characteristics in those two, especially if your temperature dips below 40 deg F or climbs above 80 def F.

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.

 

[Arnie]

Hi,

It's an exhaust: http://www.twobros.com

Gained about 10bhp, give or take. Suspension is a little firmer, but much more confidence inspiring.

J

Any issue with noise regulations with the modified/changed exhaust ?

 

[taifei]

5w40 is easier to find than 10w40. I got couple gals of honda stuff for first few changes but will be switching to the 5w40 afterwards too since I can use same oil in my car and my bike

 

[Arnie]

5w40 is easier to find than 10w40. I got couple gals of honda stuff for first few changes but will be switching to the 5w40 afterwards too since I can use same oil in my car and my bike

I wouldn't use car oil on a motorbike . Since the clutch is wet clutch and it also uses the same engine oil with the gear box on a motorbike, oils for motorbikes have different additives thus different specs even though it might have the same rating .

 

[taifei]

Rotella works fine for both car and bike, but you are right, all the eco friendly car oil with friction modifiers are bad for wet clutches. Rotella isnt one of them though.

 

[Arnie]

Rotella works fine for both car and bike, but you are right, all the eco friendly car oil with friction modifiers are bad for wet clutches. Rotella isnt one of them though.

You are right about friction modifiers but I am not too sure if that's the only criteria or not?!?

 

[Brammers]

So long as the car oil meets or exceeds MSA jp2 and api sl certification it's fine. No friction modifiers though... You'll kill the clutch with slip.

 

[Arnie]

So long as the car oil meets or exceeds MSA jp2 and api sl certification it's fine. No friction modifiers though... You'll kill the clutch with slip.

As I said I don't know the friction modifiers are the only thing to watch for or not.

 

[Brammers]

It's worth mentioning that car engine oils will not be designed to handle the shearing forces of a high-speed gearbox. Cars have separate gearbox oil for that.

Your bike, your rules. But my bike gets dedicated designed motorcycle engine oil for a reason.

J

 

[Arnie]

It's worth mentioning that car engine oils will not be designed to handle the shearing forces of a high-speed gearbox. Cars have separate gearbox oil for that.

Your bike, your rules. But my bike gets dedicated designed motorcycle engine oil for a reason.

J

Your bike, your rules. But my bike gets dedicated designed motorcycle engine oil for a reason.

Exactly, I love looking after my motorbike and using best materials to maintain it.

 

[Dankotaru]

Well, the other thread got closed and @Brammers told me to take it elsewhere. So I'm game to continue the discussion.

Replying to Baugustine:

You can make the argument that a 0W and 5W will flow better at colder temps, I don’t think anyone is disputing that. You can’t say it always provides better lubrication, that is not fact. In order for something to be true, it has to be true 100% of the time.

Well, it is a fact. It's not only just intuitive, but it's been tested to death. There's papers going back to the 60's showing that lower viscosity engine oils reduce engine wear on start-up. There's white papers out there from all kinds of organizations that have established this. The ASTM literally has cold-start testing procedures for this very reason. D5293 and D4684 measure centipoise at different temps for cold start-up because, as mentioned before, centipoise is a measure of dynamic viscosity (the amount of force necessary to move a layer of liquid). Why would this be so important? Because better flowing oil on start-up, lubricates better on start-up.

Allow me to just quote the ASTM:

"It has long been established, that the majority of wear that occurs in an engine occurs at start-up. The reason for this is that engine oil normally resides in the crankcase and must be pumped to certain areas of the engine for it to serve its purpose of lubrication. Before the oil is pumped, the engine must be cranked, or started, to engage the oil pump that transfers the engine oil. Out of necessity, the lubricant industry has studied the low-temperature cranking and pumping properties of engine oil. The result has been the creation of an engine oil viscosity classification, SAE J300, which includes requirements for winter viscosity performance.

Those ASTM requirements for 'W' weights are important because the most critical aspect of reducing engine wear at start-up is oil flow. That's a fact, and it's fairly obvious when you realize that oil gets thicker, and is harder to pump and takes longer to pressurize the oil galleries, when it gets colder. Which is why talking about a 5W being 'too thin' when it's already many times thicker than the oil at operating temp, and a 10W doing better to protect an engine at start-up, when it's harder to pump and takes longer to pressurize, makes no sense.

If your engine's oil pump and clearances were designed to operate with an oil between 9.3 and 12.4 cSt at an oil temperature of 212 degrees (that's a 30 weight oil at 100C), then you might see how it makes no sense to say that an oil viscosity many times thicker than that will be 'too thin' to protect at start-up. Literally EVERY engine oil grade is thicker than 9.3cSt at ANY ambient temperature cold start. Even if it's 120 degrees outside in Arizona, and your bike has been sitting in that sun all day, when you start the engine, the oil will still be thicker than 9.3 cSt. In fact, calculating it for our Motul oil used in the previous post, the 5W-30 will be about 49cSt, more than four times thicker than it will be at operating temp. So again, it doesn't make any sense to say that it's 'too thin'. It might even be obvious that an oil which can flow easily and properly pressurize the system quickly is better for your engine than one that doesn't.

Practically, this is why the lifters on your Boss 302 probably take a few seconds to quiet down on a cold start, but not when you start a recently shut down hot engine. Or why engine block heaters are a thing. Because the oil at start-up is plenty thick, even when it's hot outside, when compared to the operating viscosity. But cold oil doesn't flow well, and that's a problem, and why you shouldn't romp on a freshly started cold engine.

In this case, there are many examples the where the manufacturers had better testing results with something else. If it was that simple, everyone would specify one grade, the oil companies would be happy to make one product and the manufacturer would be even happier.

Well, I'd love to see those examples where a manufacturer had better test results for start-up wear in one of their engines by using a 10W-xx over a 5W or 0W-xx grade oil. I've never seen one. Truly. Even a quick search through SAE reveals dozens of papers saying the opposite, and defending my statement that this:

Careful! 5w30 is thinner at ambient than 10w30... This may cause higher wear rates during startup. I personally would favour 10w40 over 5w30 or 5w40.

J

is incorrect.

Now, I never said this was simple. I said there are a number of conditions for why a manufacturer would specify an oil grade, and I'm not arguing against Honda recommending a 10W-30 for whatever reason. I can speculate several reasons why they chose this grade over a 5w-30, most of which will have to do with shear stability at operating temperature and would be a fun discussion that incorporates more of the information you posted earlier from the Advance Auto lube guy, but one reason they didn't spec a 10W-30 over a 5W-30 is because it will protect better at start-up.