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Synthetic or Reg Oil?

25K views 43 replies 18 participants last post by  T-BoneSteve 
#1 ·
Due for 1K service. Read here somewhere the bike has a smoother shift w/synthetic.
 
#3 · (Edited)
man.... still the age old debate... I will send a link to a video that will end the debate once and for all.... Synthetic is better in everyway... Of course when I break in a motor, I use conventional, due to the 500 mile interval to change and it being cheap to do so, and it's what I have done from the beginning, an old school machinist taught me that and he did it that way for every factory rebuild and every race motor and every turbo/super setup... 40+ years he was an ASE cert'd and had a ton of experience...
 
#4 ·
I have Questions concerning the Oil. Does anyone know what SAE Grade the Harley oil is? Is it SJ? SM? This is the First Motorcycle I have owned that doesn't specify the SAE. MA or MA2? I've been using Valvoline Synthetic 20/50 SJ with MA2 ratings. The 2010 Yamaha Majesty called for SG or Higher. I used the Valvoline Synthetic 10/40 SJ MA2. 14k Miles and never had a problem.


As far as a Filter? I have been using a Bosch Distance Plus D3300 on mine.
 
#5 ·


I couldn't have said it better myself.... Every motorcycle/automobile I own, factory or performance, every turbo/super setup I do, I use synthetic.... No ifs ands or buts....
 
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#6 ·
I highly recommend Amsoil full synthetic. You will notice that the gears shift more smoothly and you will be able to shift into neutral much better. Dealer wanted around $300 - I did it myself for $60 in oil and $15 for a stainless steel K&N oil filter. BTW you may want to change the round gasket for the oil plug while you're at it. It cost $0.90 at the dealership.
 
#8 ·
Owned cars for over 25 years, including a couple with high performance tight tolerance engines. Always used conventional oil. Never had a problem. As long as you change the oil when you should, conventional works perfectly fine.

With my Street 750 I have a chatter that happens when the clutch is in the friction zone during low speed maneuvers. I did my 5k service myself and used synthetic oil this time to see if that would cut down on the chatter. It didn't make any difference at all. So I am likely going back to conventional from here out. YMMV.
 
#9 ·
Exactly my point.... Did you not see the comparison video? And that was 25+ years in the past.... Things, including technology have changed... Some still hold true, others have changed with the times.... That's coming from a mechanical/engineering background with pictures, numbers, and logs of rebuilds and experience? Or is that coming from a customers standpoint in not believing in the price and kept conventional for that reason? You cannot convince me otherwise to switch from fully synthetic to conventional, other than an engine rebuild/break-in....

And we all know the shifting system in our Street models isn't exactly performance either... Mostly the foot controls and lever...
 
#11 ·
Who is the engineer? You or the Youtuber that I sent the link on? Well if you don't have black and white numbers, proof to back it up, then I would say it's farfetch'd... 130k and never an oil change? 130k with 3k intense service intervals? Or 130k with what? I know plenty of cars with oil related problems... Chrysler 2.5, 2.7, 3.0. 3.5 HO, I could keep going and going and going.... And plenty of vehicles nowadays get shipped from the factory with synthetic oil and already changed the intervals in the service manuals to 5k or 7.5k whatever they made them to be... Price to you doesn't mean anything, but I know plenty of people that are cheap as all **** with their cars, I work on them daily for custom high paying jobs or basic repair and maintenance, some people will spend the $$$ to do it right, others want to literally cut corners and get it out the door....

Of course, tomato tomatoe.... but real live numbers, logs, and data doesn't lie.. See for yourself.... One test amongst many others proves that...
 
#12 ·
Did you intentionally not read? Are you intentionally trying to pick an argument? I don't really care enough to participate if that is the case.

I am an engineer. Went to the university of Louisville Engineering school. The guy in the video probably is too. Good for him.

I clearly said with proper maintenance. Meaning if you change the oil and filter when you are supposed to, then conventional will work fine and make a car last a long, long time. For me, I have never had a car where the engine didn't outlast the rest of the car easily.

I have been driving Japanese and German cars since 1992 and have had no oil issues with any of those. I only know of one person who has ever had an oil issue with a Japanese engine and that was a guy driving a 1986 Toyota Supra who put in a racing cam, and twin turbos. He kept burning up one of the cylinders as the oil pump couldn't keep up.

I also said I believe in using whatever the car was shipped with. So if as you say, you receive a car that came from the factory with Synthetic oil, then you should certainly use Synthetic oil. Just saying it is probably overkill for most other engines that were designed to run on conventional. Oh, and many cars have extended the service intervals for oil changes when running conventional too. That isn't just a synthetic thing.

Can we agree that doing an oil change when you are supposed to is probably more important than the oil you put in?
 
#22 ·
Of course, the world engines... And I know a lot of times it is cross referenced to newer or different cars due to the same diameter and thread pitch for the filters being used...
 
#23 ·
yeah synthetic all the way got the h d 20/50 in my 2015 street 500 and it shifts noticeably smoother been runnin mobil one in all my cages since the 80's in the motor ,tranny, and the punkin it'll get dirty, but it doesnt break down like organic ; it still stays slick i asked the service tech when i bought the harley what he thinks about mobil one "NO AUTOMOBILE PRODUCTS' whoa! ok! i run the mobil one in this little scooter i got and its comin up on 24.000 miles doesnt burn any oil, runs like a champ, and its still slick at a 2000 plus oil change and hey i heard a while back that all the pennsylvania oils got parrafin in them anybody ever hear that?
 
#24 ·
Hopefully this thread is OK to revive for this inquiry:

I changed the oil on my 2017 Street Rod and used Mobil 1 V-Twin 20W-50. It works fine! The engine actually sounds a bit smoother, though that could be all in my head.

However, the shifts are definitely "clunkier". It shifts fine, but there is a bit louder "thunk" on many shifts. Has anyone else experienced anything like this?

It's not a problem at all, but just kind of a funny thing.
 
#25 · (Edited)
Interestingly Mobil 1 V-Twin is NOT JASO MA rated for wet clutches even though the Mobil 1 site it is for use with wet clutches. "Mobil 1 V-Twin 20W-50 engine oil is designed to help provide the proper frictional characteristics necessary for wet-clutch common engine/transmission systems." (Email sent to Exxon-Mobil on this topic)

My buddy uses it in his Honda XR250 and the top end is quiet and no clutch issues. I was about to try it in my Street Rod but opted for Valvoline full synthetic 20W-50 MC oil as it was on sale for $7.86 per quart so I thought I would give it a try. My Street Rod has a grabby clutch when the oil is cold so I was wondering if perhaps an oil change might help.

FYI I use Shell Rotella T6 oil in all the other air-cooled bikes and it has been a very good oil for our needs. Very nice clutch and shift action with Shell Rotella T6 oil.

No idea what oil was in the engine but it had likely 2,900 miles of use as the bike has 3,900 miles on the clock. After the oil change cold clutch action was much improved but hot clutch action was about the same. I have ridden a LOT of bikes and I rate this clutch as mediocre. That combined with twitchy throttle results in extra finger work from a full stop.

Engine sounds the same cold but is a just bit quieter when warm. It's brand new oil so I attribute any less noise to that alone.
Shifting is a bit better and a bit quieter and neutral is easier to find but I also attribute that to brand new oil as well.

So... No extra noise, which I have read riders complain about SYN3 resulting in top-end noise, so that is good. Better cold clutch action so that is also good. I used a NAPA oil filter (by WIX) P/N 1358. It appears to be a high-quality item.

So... What's the verdict? For $7.86 a quart for full synthetic JASO MA/MA2 rated MC oil I am happy...
 
#26 ·
Direct from Exxon Mobil:

"Mobil 1 V-Twin 20W-50 does not meet the requirements of JASO MA/MA2 and is not intended for these applications. Our JASO MA/MA2 approved fluid is Mobil 1 Racing 4T 10W-40."

"I forgot to mention that we have no listing of this motorcycle. Please refer to your owner’s manual or contact the OEM directly to inquire about lubrication requirements."

"At one time, this product did have JASO MA approval.

Due to the increasing use of catalytic converters, the phosphorus content requirement to meet this specification was reduced. At this time, with our product being a very popular option among motorcycle enthusiasts, it was decided to leave the phosphorus content at its original level, therefore disqualifying it from JASO approvals.

We still stand behind the product for outstanding protection in four-cycle, V-Twin type engines – particularly those that are air-cooled and tend to run hotter than other types of engines. This product does indeed have the proper frictional characteristics necessary for wet-clutch common engine/transmission systems, we just wouldn’t recommend it if JASO MA/MA2 is an OEM requirement as this could lead to damage of catalytic converters and potentially void warranties."
 
#27 ·
I switched to Castrol POWER1 V-TWIN 4T 20W-50 Full Synthetic in my street a couple hundred miles ago for my 5K service, seems to run a little smoother and shifting is less "clunky" here. As for as an oil filter, I couldn't find a KN-204 anywhere locally so I just grabbed a cheapy Fram PH6017A from Walmart. Haven't had any issues yet and doubt that I will. All in all it cost me about $50 for the oil, 3 drain plug o-rings (just in case), the filter, and a drain pan.
 
#28 · (Edited)
I just changed my oil to Valvoline 20W-50 full synthetic. It was on sale for $7.86 per quart so I figured I'd give it a try. I used a NAPA oil filter which is made by WIX and looks to be of high quality.

My XG750A Street Rod required all three quarts to get to the middle of the "X" on the dipstick when hot. Three full quarts of old oil came out as well. Old oil was still pretty clean and no debris on the drain plug magnet.

Clutch action, especially when cold, is much improved. Shifting is better and quieter, finding neutral is easier, and top-end sound is slightly reduced.

Thinking of trying Twin Power next: https://twinpower-usa.com/oil-and-filters/twin-power-20w50-synthetic-engine-oil.html
 
#31 ·
my take is when buying oil that fits my bike/car

Good Brand Mineral oil 4 lt - usd21
Good Synthetic Oil 4 lt - usd40

Oil and filter change every 5,000km (3,100miles), i use synthetic. (for cars its 10,000km)
oil and filter change every 2,000km (1,200miles), i use mineral. (for cars its 5,000km)

unfortunately my 750 needs to go back to the ex.Harley importer as warranty till 2020, however this time round they use AMSOIL V-Twin.
Due to limited spare parts here (washer and oil filter), no choice but to go back to official Harley after warranty over.
 
#32 ·
Just for fun I changed the oil in my XG750A from Mobil 1 V-twin 20W-50 to Valvoline 4-stroke 20W-50.

I changed it because when I put in the Mobil 1 V-twin the shifting got noticeably "clunkier". Then I found out from VortecCPI that Mobil 1 V-twin is not "JASO MA" approved any more, which can affect clutch and shifting.

Anyway, going to the Valvoline reduced shift clunkiness about 80%. Fantastic! Thanks Vortec!
 
#36 ·
Thanks to everyone in this thread for the info.
And thanks to T-BoneSteve for the clarification on the Valvoline.
I stood in front of the oil shelf for longer than I should have debating oil. So I pulled the trigger on the Valvoline 4 Stroke Synthetic 20w-50. $7.49 a qt.
I parked the bike and drained the oil. Every last drop. Then the filter. I put in the new 20/50. Did a cold check. Warmed up the bike and did several hot checks.
I am thrilled with the results!. The engine sounds so much better. The clutch is more predictable and smooth. That major clunk while shifting gears is substantially reduced. And it seems that the high rev vibes are reduced on the freeway.
 
#37 ·
I have one question about engine oil for our Streets: can i use 10w50? Synthetic 20w50 in most cases are dedicated to HD which means -> EXPENSIVE ;) 10w50 are more common and cost half the price plus have (in my opinion) better viscosity index. Additionally in the manual we have a statement, that if HD oil is not available one may use 20w50, 15w50 or 10w40... Why they didn't mention 10w50?! Are there any reasons for this?
 
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