Anybody got any comments on whether I should use a 5w50 (Castrol Syntec) instead of the 20w50 the engine manufacturer recommends. I don't suppose I should say what I'm putting it in because everybody seems to clam up and won't talk much about motorcycles, but it's for my '00 Harley Twin Cam 88. I'm going to do a dose of Auto RX so I needed a non-synthetic (Frank said Group III was OK) to run for only 750 miles and had a freebie from Sears ($20 gift card because they didn't change my tire in an hour). The Castrol 5w50 was the only 50 weight they had that was diesel rated (what Harley recommends if their oil isn't used). Anybody got any viscosity numbers on the 5w50? Castrol doesn't put MSDS's on the web and there are no VOA's or UOA's on this stuff, but in the Why-buy-any-other-synthetic-than-Mobil-1 thread someone suggested that the 5w50 might hold up better than M1 15w50 (which I am considering using later on). But since I'm only going to run it 750 miles, should I care just about the lower limits of protection rather than about the upper limits? BYW, the ambient temperatures here in Alabama are still in the 70's at night but it can get well into the 90's during the day.
Use 5w50 instead of 20w50
- Thread starter doyall
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All else being equal, I would think that a narrow range oil like 15w50 would be more shear stable than a wider range like 5w50.
Theoretically the 5w50 might give you less wear on cold starts, but would be more likely to shear down.
Why are you only running the oil for 750 miles? If your interval is that short it's not going to have a chance to deteriorate so you can run just about any oil of the recommended weight.
Doing an Auto RX treatment.
You may get a lot better response if you posted your question in the MOTORCYCLE thread on this board.
doyall, I think Castrol Syntec will be fine for a short interval in your Harley.
Syntec 5W-50 data:
ACEA A3/B3 and API SL/CF
[ August 22, 2003, 07:30 PM: Message edited by: Sin City ]
Syntec 5W-50 data:
ACEA A3/B3 and API SL/CF
I would be very surprised if you had any trouble from running 5W-50 for such a short interval. I would however suggest keeping the AutoRX in a little longer. 850-1,000 miles might be a good idea to be sure you get all of the crud out of your motor. You would not want to have to order more AutoRX just to remove a little leftover crud. While I think Syntec 5W-50 is an OK choice for this short interval I think a fully synthetic 15W-50 or 20W-50 is a better choice for a normal oil change routine in a Harley. I would have purchased the Syntec 5W-50 if I had that coupon so I agree that you made a good decision.
[ August 22, 2003, 07:30 PM: Message edited by: Sin City ]
If your going to use either one 'exclusively', then I would go with the Mobile 15w-50. Especially in a Harley. I think after you read the various posts on either of these oils, M1 wins out.
I would not use Syntec 5W50 in anything. First it is not a true synthetic it is group III conventional oil. Second the group III oils are only good up to 30Wt. so alot of VII's have to be added to get that spread of 5W50. VII's do nothing to lubricate or protect. If you are going to spend that time of money for a 50Wt. get the M1 15W50.
Wouldn't even consider running the Syntec 5w50 on a full time basis, especially after seeing the cSt @ 100C visc (very low 50 weight). Thanks for the specs SinCity. I needed to use my freebie and it was the only thing Sears had that was close to what I needed. Thinking about taking it to WalMart and swapping it for 20w50 if they sell 5w50 here. (As for the M1 15w50, I remain concerned about its cSt @ 100C visc of 17.4.)
If you want a high 50 try one of the HDMO 50s.
Typically they have a cSt of around 19.5, meet several cross transmission/engine catagories such as Allison C-4 and Caterpillar TO-2 wet clutch/brake drive-line spec.
Price?? About $1.70 a quart.
Why do you think big bore air cooled aircraft piston engines use SAE 50 and 60 weight engine oils?
Would you like a Goldwing to go with that 10W30 oil sir?
Typically they have a cSt of around 19.5, meet several cross transmission/engine catagories such as Allison C-4 and Caterpillar TO-2 wet clutch/brake drive-line spec.
Price?? About $1.70 a quart.
Why do you think big bore air cooled aircraft piston engines use SAE 50 and 60 weight engine oils?
Would you like a Goldwing to go with that 10W30 oil sir?
If your bike specified 20W50 and you used SAE 50 instead, would you do any harm?
Not unless you are starting your bike in cold weather.
Do you need 5W protection for your application that would allow cold starts at -35C?
If you do, your a better man than me.
Not unless you are starting your bike in cold weather.
Do you need 5W protection for your application that would allow cold starts at -35C?
If you do, your a better man than me.
Doyall; What kind of discussion are you looking for?
The AMSoil guys are going to tell you to use AMSoil, the Redline salesmen lurking on theis site
are going to say use Redline, people who like Mobil I will tell you to use Mobil I, and so on.
That is all you are going to get.
There is no magic to all of this oil talk.
Do you really want an oil with a VI improver in it for your Hog?
Do you want oil or banannas?
What do you think you should put in your motorcycle, forget the wet clutch argument, it does not apply to you?
Obviously you want an SAE 50 engine oil, judging from your posts.
Would you like cold start protection with that 50 weight?
If so pick a multi-grade.
If you pick a mineral based multi-grade engine oil, say 20W50 it will more than likely have quite a bit of VI improver in it.
If you pick a 15W50 synthetic engine oil it may not have any VI improver in it, but you are going to pay the higher price for that.
Can annyone but the oil company in question tell you how the 5W50 was blended to achieve such a wide temperature service classification?
No.
It could very well be a very light group III with VI improvers added to it, or it could be a very expensive PAO ester blend without any VI improvers.
We do not know.
What I do know is that HDMO SAE 50 weight engine oils have no VI improvers.
How can I tell that?
Because they meet CF-2 Detroit Diesel specs, that specify no VI improvers.
Doall, this ain't rocket science, so don't try and read more into all of this oil talk than what is necessary.
Leave that for the obsessive compulsives.
The AMSoil guys are going to tell you to use AMSoil, the Redline salesmen lurking on theis site
are going to say use Redline, people who like Mobil I will tell you to use Mobil I, and so on.
That is all you are going to get.
There is no magic to all of this oil talk.
Do you really want an oil with a VI improver in it for your Hog?
Do you want oil or banannas?
What do you think you should put in your motorcycle, forget the wet clutch argument, it does not apply to you?
Obviously you want an SAE 50 engine oil, judging from your posts.
Would you like cold start protection with that 50 weight?
If so pick a multi-grade.
If you pick a mineral based multi-grade engine oil, say 20W50 it will more than likely have quite a bit of VI improver in it.
If you pick a 15W50 synthetic engine oil it may not have any VI improver in it, but you are going to pay the higher price for that.
Can annyone but the oil company in question tell you how the 5W50 was blended to achieve such a wide temperature service classification?
No.
It could very well be a very light group III with VI improvers added to it, or it could be a very expensive PAO ester blend without any VI improvers.
We do not know.
What I do know is that HDMO SAE 50 weight engine oils have no VI improvers.
How can I tell that?
Because they meet CF-2 Detroit Diesel specs, that specify no VI improvers.
Doall, this ain't rocket science, so don't try and read more into all of this oil talk than what is necessary.
Leave that for the obsessive compulsives.
userfriendly, I merely thought that IF IT WERE SO, some engineer, chemist or physicist on the board might say something like "a 5 weight base oil in 90+ degree temperatures in an air-cooled shear-monster Harley would be insufficient at all three states of lubrication within the period of time you are contemplating, so don't use it." While it isn't rocket science, it is science above my level. I was really looking for the type of analysis MRC01 and SinCity provided. Anyway, it's a moot point now becase WalMart swapped it for some 20w50. (They sure are easy!) Having seen from UOA's how Harleys will shear-down a high 50 weight within a few thousand miles, I am just exercising an over-abundance of caution with such an expensive toy.
[ August 23, 2003, 10:24 PM: Message edited by: doyall ]
[ August 23, 2003, 10:24 PM: Message edited by: doyall ]
1st off, 10 years ago Castrol Syntec would not be a synthetic oil. It is a group III base. Had API not relaxed the spec. in early 90s. It would be a dino oil base. In Japan Syntec would still not be a synthetic oil. Why not use a PAO base in synthetic? it is about the same price. Mobil or Amsoil might be worth looking at.
[ August 23, 2003, 10:34 PM: Message edited by: Hirev ]
[ August 23, 2003, 10:34 PM: Message edited by: Hirev ]
Doyall,
after reading the thread, I think you might be safer using the 20w-50 with the harley shearing the oil.
I say this for one reason, it would not have as many viscosity improvers as an oil with a larger weight spread. Less vi would mean more base oil and hopefully hold up longer with the shear problem.
Would you also post your thoughts when the arx treatment is done and let us know what you think of the product--good or bad.
Dan
[ August 23, 2003, 10:36 PM: Message edited by: Dan4510 ]
after reading the thread, I think you might be safer using the 20w-50 with the harley shearing the oil.
I say this for one reason, it would not have as many viscosity improvers as an oil with a larger weight spread. Less vi would mean more base oil and hopefully hold up longer with the shear problem.
Would you also post your thoughts when the arx treatment is done and let us know what you think of the product--good or bad.
Dan
[ August 23, 2003, 10:36 PM: Message edited by: Dan4510 ]
99% of the people I talk to that ride HOGs use one of three oils. 20w-50 HD, 20w-50 Castrol, or 15w-50 M1. The only thing I ever see come off these engines is the cylinders--- to be replaced by bigger bore cylinders!
Dan4510, if you are out there, I posted to the other section in hopes of engaging some of the more knowledgable "oil heads" who might not otherwise visit the motorcycle section. At its core the question really was "if mfgr specs 20w50 will 5w50 do harm." I could have just left he motorcycle stuff off but thought it might be beneficial for some. These Harleys are not like exotic Italian or high-tech Japanese bikes (they are relatively primatave in comparison) and do not have shared sumps with clutches or trannies. In my mind, the basic issues are not that much different than your standard internal combustion engine. A few different considerations must be factored in but I can't help but think that that should stimulate peoples thinking. Perhaps if the experts on this forum realized this they would be more willing to engage in a discussion of motorcycle lubrication. Not trying to flame or dis anybody so please take no offense. Like everyone else here I am just trying to figure out how to take the best care of my equipment, be it a car, truck, motorcycle, boat or lawn mower.
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