Does small engine needs synthetics?

[MasKaz]

Hello there, I'm a complete noob in motorcycle and oil so I need guidance from oil expert and enthusiast like you guys.

My motorcycle is an entry-level air-cooled 150cc from Honda. It's still in break-in process, currently sitting at 1600 km. I already changed the oil three times at 300, 800, and 1500 km. Still using mineral oil as its the recommended oil for breaking in.

I'm planning to switch to M1 semi-synth at 2500 km, and start using Repsol/Castrol full synth at 8500 km. But when I look at both full synth oil's technical datasheet, it was meant for medium and high performance engine. While my bike's top speed is only 70mph at 9000 rpm, and it won't go any higher no matter what

So my question is, as written on title, does small engine needs synthetics? Is it worth it, or is it just waste of money?

Additional question, I live in tropical country where the temp can go to 100°F all year long. From what I've read the most suitable oil weight is 10w-40, but the manufacturer recommends 10w-30. My other consideration, the options for 10w-30 semi/full synth oil is thin! Rotella T6 is non-existent in here, so yeah, that's why I chose Repsol/Castrol (both have 10w-40 viscosity) for my future oil. Should I stick with the manual or should I go with thicker oil?

Your reply and suggestion will be much appreciated!
Thanks!

 

[HangFire]

Does your motorcycle share a wet sump transmission with the engine?

 

[MasKaz]

Does that mean wet clutch? If it is, then yes the oil shared with transmission.

Here she is

 

[andyd]

Thickest oil you can find easily. Isn't there a chart for which oil to use in temp range. 32-120F? I favor 20w50. Conventional or synthetic has little meaning these days. Air cooled motor cycle oil.

 

[Silverado12]

20W-50 would more than likely work the best in a hot climate. If you can get Rotella or the equivalent in 15W-40 that should be ok too and cheaper.

 

[4WD]

Apa Kabar Pak … 10w30 is widely used in air cooled engines in hot climates - I'd be afraid a really thick oil will just rob HP or create more heat.

Delo 10w30 is a stout semi synthetic that competes with Rotella - maybe you have it there from Caltex ?

 

[Silk]

I'd go with a monograde SAE30, it'll never have a cold start problem, never shear and handle the heat just fine.

 

[ChrisD46]

I believe a 10W30 Mobil 1 , Castrol 10W30 , Pennzoil Platinum 10W30 (all synthetics) would do just fine in your bike (very nice by the way !) ... Just follow the owners manual but any of the oils I mentioned would be fine - remember changing the oil on schedule is most important .

 

[Jarlaxle]

Air-cooled, I would use synthetic oil. Air cooled engines run HOT.

 

[ammolab]

You want a JASO spec oil for your wet clutch and any of the synthetic 10W-40 Motorcycle oils would work fine in your climate.

 

[Papa Bear]

I have a 2013 SYM Classic Wolf 150 https://www.alliancepowersports.com/models/wolf.html and it has had pretty well a steady diet of Shell Rotella T (T4) 15W-40 all it's life.
It is a knock-off of the CB125 (SYM built CB125 under contract for Honda)
I bought the bike new and I'm coming up on 42,000Km, the bike runs/shifts like new. The T4 is dirt cheap and I change it @~ 2,000Km intervals (1L)
Shell Rotella T (T4) is JASO MA spec'd - I would argue it is all you will ever "need" ......
Enjoy your new ride !!
Papa Bear

 

[Cujet]

There is no question that a well chosen, quality synthetic oil has very positive properties. Including the ability to have excellent viscosity at very high temperatures. The HTHS specification is one that I look at very carefully when choosing an oil for an air cooled engine. I live in Hot-n-Sticky Florida. Air cooled engines can suffer here. I look for an HTHS of 3.8 or higher for my uses.

As we know, viscosity is the property of oil that provides lubrication. When viscosity is too low, certain components tend to wear more rapidly. This includes things like motorcycle camshaft followers/rocker arms and timing chains.

People tend to look at piston ring and cylinder wear as if it's the only type of engine wear to consider. Mostly because it's the most visible failure. However, complex designs will often have certain components failing before others.

Then we need to consider that the high temperatures of air cooled engines can lead to deposit formation with low quality oils. Especially on piston ring lands, where excess carbon can degrade ring sealing and allow blowby.

The truth is that transmission gears, ball bearings, roller bearings (such as some motorcycle connecting rods) and plain bearings will all hold up fairly well with low viscosity oils. Ring and cylinder wear is only slightly increased with low viscosity. But motorcycle timing chains and camshaft/follower wear can be very problematic with low viscosity.

The suggestion above, a robust diesel oil is a great one. It's cheap enough to change often, tough and can handle anything that little engine can dish out.

How about Mobil 1, 10W-40 racing 4t (MX4t) ?

Note: I prefer frequent oil changes, as the oil change is the only way to remove wear causing contamination and particulates.

 

[Superflan]

+1 on what Cujet said.

Do you have access to those 20W40 oils in your country?

In Reunion Island you'll struggle to find any wild available xxW30 motorcycle oil. People uses 10W40 in various brands, some go for 15w50, 10w50, or some xxw60 amongst KTM users (hello Motorex).

Never had a problem running 10w40 where 30 is specified, although on my former 2013 Honda CB500X it would shear in the first kilometers to be more like a 30 grade (you would feel the power robbing when some 40 oils were new)

 

[ZeeOSix]

Originally Posted by MasKaz
Additional question, I live in tropical country where the temp can go to 100°F all year long. From what I've read the most suitable oil weight is 10w-40, but the manufacturer recommends 10w-30.


I'd run a good 10W-40. If you're doing short oil changes then conventional will work fine. Can you get Valvoline conventional 4-stroke motorcycle oil there? Lots of guys run that Valvoline and like it. I've used it in both my XSR900 and Hayabusa.

 

[alarmguy]

No engine needs synthetic if the manufacturer doesnt call for it and if you change at the proper intervals. Your engine will last just as long and actually might have less wear with conventional.

You have a really cool looking bike by the way! Why not listen to Honda and follow the owners manual>?

 

[Bonz]

Help me understand how there might be less wear with conventional oil? Not saying a synthetic is the be-all or end-all for less wear, however I would not think it sacrifices anyting to a conventional oil either. I would think syn and conv would be at least equal on all counts given similar additive packages and weight ranges.

 

[MasKaz]

Wow I wasn't expecting for lots of response, thanks guys!

Originally Posted by andyd
Thickest oil you can find easily. Isn't there a chart for which oil to use in temp range. 32-120F? I favor 20w50. Conventional or synthetic has little meaning these days. Air cooled motor cycle oil.

Originally Posted by Silverado12
20W-50 would more than likely work the best in a hot climate. If you can get Rotella or the equivalent in 15W-40 that should be ok too and cheaper.

Yes I have seen the chart, that's why I'm considering thicker oil (but not as thick as 20w50). I will consider 20w50 when my engine is old enough, as I read that the newer engines have narrower clearances and smaller oil paths. Is it also true!?


Originally Posted by 4WD
Apa Kabar Pak … 10w30 is widely used in air cooled engines in hot climates - I'd be afraid a really thick oil will just rob HP or create more heat.

Delo 10w30 is a stout semi synthetic that competes with Rotella - maybe you have it there from Caltex ?

Kabar baik! Yes Caltex Delo is available here, but it clearly states not for motorcycle use. Perhaps because it doesn't meet JASO MA requirements? But I just find out Caltex have Havoline intended for motorcycle and they seems to be a good engine oil too.


Originally Posted by Silk
I'd go with a monograde SAE30, it'll never have a cold start problem, never shear and handle the heat just fine.

Nice idea! Unfortunately I haven't found any monograde oil for motorcycle available here.


Originally Posted by ChrisD46
I believe a 10W30 Mobil 1 , Castrol 10W30 , Pennzoil Platinum 10W30 (all synthetics) would do just fine in your bike (very nice by the way !) ... Just follow the owners manual but any of the oils I mentioned would be fine - remember changing the oil on schedule is most important .

Originally Posted by alarmguy
No engine needs synthetic if the manufacturer doesnt call for it and if you change at the proper intervals. Your engine will last just as long and actually might have less wear with conventional.

You have a really cool looking bike by the way! Why not listen to Honda and follow the owners manual?

Thanks! I'm considering 10w40 because it is more suitable for tropical climate, and it has larger options! I also disappointed by the oil provided by Honda, as it only good for the first 100 km. Noisy and hot engine, many clutch slips, lots of vibration, and many more...

 

[MasKaz]

Originally Posted by Papa Bear
I have a 2013 SYM Classic Wolf 150 https://www.alliancepowersports.com/models/wolf.html and it has had pretty well a steady diet of Shell Rotella T (T4) 15W-40 all it's life.
Shell Rotella T (T4) is JASO MA spec'd - I would argue it is all you will ever "need" ......
Enjoy your new ride !!

Thanks! And wow it has similar look only in chrome accent! Unfortunately Rotella is not available here. The diesel oil provided by Shell here is Rimula, and it has energy conserving label on it (the owner manual prohibits any energy/resource conserving oil)


Originally Posted by Cujet
There is no question that a well chosen, quality synthetic oil has very positive properties. Including the ability to have excellent viscosity at very high temperatures. The HTHS specification is one that I look at very carefully when choosing an oil for an air cooled engine. I live in Hot-n-Sticky Florida. Air cooled engines can suffer here. I look for an HTHS of 3.8 or higher for my uses.

How about Mobil 1, 10W-40 racing 4t (MX4t) ?

First of all, thank you for your comprehensive explanation.
I read good reviews on M1 Racing 4T. The problem is it's hard to get and rather pricey, almost twice the price of Repsol/Castrol (similar technical specs). So I prefer the much cheaper and easy to get options.
Where can I get the HTHS number? I never seen them on any provided PDS.


Originally Posted by Superflan
Do you have access to those 20W40 oils in your country?

Never had a problem running 10w40 where 30 is specified, although on my former 2013 Honda CB500X it would shear in the first kilometers to be more like a 30 grade (you would feel the power robbing when some 40 oils were new)


Most 20w40 available here are intended for scooter. 20w50 are widely available but as stated above, I will use it when my engine is older. I won't mind 10w40 robs power, since it's not so powerful in first place lol!


Originally Posted by ZeeOSix
I'd run a good 10W-40. If you're doing short oil changes then conventional will work fine. Can you get Valvoline conventional 4-stroke motorcycle oil there? Lots of guys run that Valvoline and like it. I've used it in both my XSR900 and Hayabusa.

Yes they're available. I don't know about them, but most conventional oil can only last for 1500 km here! Conventional oil will degrade quickly, thanks to hot climate and start-stop chaotic road condition. I hope I can get 4000-6000 OCI with synthetics to reduce used oil waste.

 

[Cujet]

Originally Posted by MasKaz

Where can I get the HTHS number? I never seen them on any provided PDS.

I hope I can get 4000-6000 OCI with synthetics to reduce used oil waste.


The HTHS specification is viscosity at 150c. It may be listed that way.

I suggest against long drain intervals if you want to maximize engine life. Wear causing particulates and unburned fuel, unburned fuel residue and combustion byproducts contaminate the oil. The oil change is the only practical way to remove such contamination. "Maybe" it's better to recycle more frequently changed oil than to suffer timing chain, cam and follower wear due to accumulation of soot in infrequently changed oil.

 

[andyd]

How much oil is a full sump? On something that can run at 9000 rpm, I would want clean oil. Also on a small aircoole engine, I would expect a certain amount of consumption, so frequent checks .