Motorcycles with a shared sump and a wet clutch create a bigger challenge for the oil to protect everything well. If you only saw the 6th gear with some noticeable wear with a 20W-50 motorcycle oil, then it could be a gear material/hardness factor. Gear "pitting" may be different than what you saw on your 6th gear. Per this chart, more viscosity helps prevent wear, as it always does for any two moving parts rubbing together (simple Tribology).
Amsoil metric oil
- Thread starter tjakes680
- Start date
Yeah, that's why ALL BMW motorcycles run 5W-40 since 2015
What did that do for them?Yeah, that's why ALL BMW motorcycles run 5W-40 since 2015
Nothing bad ... their bikes run 100k ... 200k ... even more miles with that oil ... point is that the table up there is misleading!
So 5w-40's HTHS isn't listed in the table, but 5w-40 oils must start at 3.5cst for HTHS viscosity in SAE J300.
clear to me--what isn't to you?If it's about the "5W" part, the fact is the HTHS of a 5W-40 is still going to be higher than a xW-30.Yeah, that's why ALL BMW motorcycles run 5W-40 since 2015
My testing showed 5w40 diesils in a motorcycle engine, the results are bout like a 10w40 car oil, usable but nothing special.
15w40 amsoil HD marine diesel, fares alot better, or is a step up.
15w40 amsoil HD marine diesel, fares alot better, or is a step up.
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Also street bikes with larger gears and holding 3 or 4 quarts of oil , are differnt than small race motors, that hold 1.5 quart of oil and gearing designed to be more narrow in physical size.
(a little joke) As I'm sure Astro knows, try flying a single engine plane a long distance over water, especially at night. The engine suddenly makes all sorts of noises it never made before.... The vast majority of the time, the noises mysteriously go away on the next flight.
All kidding aside, I've had some oils make an engine run smoother. I've always attributed it to ring sealing, an oil that does a better job of remaining on the cylinder walls and sealing the rings (generally due to viscosity) can reduce consumption and result in perceptible changes in feel/sound. Also, some additives can change the sound internally lubricated gears make.
The 20w50 Valvoline Dino oil, has very good /strong clutch grip, but the full synthetic version, will cause clutch slip in a ktm, even though ma2 rated. Baffled my mind.
Maxima proplus 10w50 has strong clutch grip or mobil 1 super 1300 strong, clutch grip
I had the same experience with my son's KTM Duke 200. Valvoline Dino 4T in 10W-40 (it's viscosity specs are actually 20W-40) is an excellent oil! I also run it in my classic 1978 Yamaha XS1100 F and it's cheap. $32 for 6 qts. from time to time on amazon. I tried Castrol Actevo 10W-40 in that bike and the clutch immediately started slipping.
So really this points at KTM clutch material selection not Amsoil.
Does metric oil come in liters or is still in quarts?
I've done a couple of D&F's on my CVT using Aisin branded CVT fluid. Word is that 2L is what comes out thus it needs 2L put back in. But this Aisin branded CVT fluid comes in... quarts? Obviously I can figure this one out, but it's always struck me as odd. [yes I get it, Aisin doesn't make oil and I'm sure it's cheaper to use quart bottles. But why does my soda, bottled in the USA, come in liter bottles while oil for my Asian import come in quarts?]
I've done a couple of D&F's on my CVT using Aisin branded CVT fluid. Word is that 2L is what comes out thus it needs 2L put back in. But this Aisin branded CVT fluid comes in... quarts? Obviously I can figure this one out, but it's always struck me as odd. [yes I get it, Aisin doesn't make oil and I'm sure it's cheaper to use quart bottles. But why does my soda, bottled in the USA, come in liter bottles while oil for my Asian import come in quarts?]
Not really since those KTM's run fine with a bunch of other MC oils and no problem.
But not all oils work in all bikes, agree on this? You even gave an example.
Yours is the only example of Amsoil MC oil slipping.
Quarts.
Of course! Mine is the only known example here ... I am sure it is not an isolated case and there are many more out there. KTM might need oil on the grabby side and Amsoil might be on the slippery side of any specs. I am not badmouthing Amsoil since I am a preferred customer and have used Amsoil for over 20 years. I like it, but this is an issue that can't be talked away. Just realize it might be an issue and we'll all move on.
The design of the wet-clutch will have a big effect on how it works with different oils. For instance, if the overall clutch is designed to result in more force per the available clutch plate area (depends on clutch plate size and plate number) and clutch spring force (depends on pressure plate size and springs), then it's going to need an oil with more friction for it to not slip under the max torque forces it experiences. If a wet-clutch is "over designed" it will not be as sensitive to the oil's friction level like a boarder line or under designed clutch will be.
Like On my ktm with valvoline synthetic , I didnt assume it was the oil, i replaced entire clutch pack plus increased to a heavier spring, made no differnce.
couldnt be the oil, but I swapped it and it was the oil , that was years ago, still riding the bike, but to use up that synthetic, i only use like half quart at a time, to avoid issue. some goes in my truck, some lawn mower ect, have like ten quarts to get rid of.
Wonder if you got a bad batch of oil. If it did that in your case even after a clutch rebuild with stiffer springs, I'd think all kinds of bikes using it would do the same thing.
