So i heard something very interesting from a buddy of mine that builds choppers. Do Not use fully synthetic oils in your HD engine due to the roller bearings inside the engine. The Syn oils are too slippery and will not allow you roller bearings to "roll" thereby causing them to flat spot. This guy's not stupid he is a turbine mech by trade and a custom bike builder by hobby. This maks a lot of sense. needless to say in 500miles my SG with get the semi syn. Also on my 06 SG I have a little bit of a clicking or rattling sound at higher rpms when i'm cranking through the gears. I'm not sure if it's normal or not. I realize HD TC88's make an *** load of noise but it sounds like a Valve "knock" to me. Anyone else have this issue?? Or know what it is and how to rid myself from it other than SYN oils. Oh yeah running stock exhaust still i haven't decided on a direction yet. Any help is appreciated.

 

I am no expert. I do not even have possession of my new bike yet. But I can turn a wrench for fun. Over the years I have talked to many people and read a lot of interesting stuff about synthetic oil. I do not use synthetic in my ATC's (yes, ATC's) because it is a bit too slippery for the clutches. I was told that synthetic WILL find vulnerable spots in your engine and start to leak because it is so slippery and fine. I experienced this with an old Ford Explorer I had. But it was old. The not so slick regular oil did better because it did not seep through the old gaskets and seals. Ever since I used the synthetic, I had those tiny oil spots under the truck.

I was even told to stay away from synthetic while breaking in a new engine because it is too slippery for the rings to properly seal, and the bearings to properly wear. Makes sense to me.

I like to trust the investments HD (or any manufacturer) put into the design and build of their products. If HD sold the bikes with synthetic, then I would continue to use synthetic oil. But they are built, tested and designed with non-synthetic oils. I am sure it probably doesn't hurt one bit to use synthetic on something brand new, but broken in. I have always owned old used and abused stuff, so couldn't really say for sure if it was worth using synthetic.

My personal preference... I use a good name brand regular oil.

Like I said, I am no expert. I do not even have a HD yet. Everyone has their own preferences and opinions.

 

The best advice I can give you is go to the oil forums we have here on the web site....we have a TON of info. there!

But, I'll break it down quick for ya!

Synthetic oil is better due to the fact that it does not break down under heat like conventional oil does! Here's MY PERSONSAL recommendation.....

Use conventional oil until your engine is broken in. Lots of people tote certain mileage numbers, but it's easy to tell on a H/D because the engine will quit running as hot as it did when it was new....Susie felt like I was sitting on a wood stove when she was new![:'(]

Go with,

Redline Shockproof Heavy oil in the transmission. Pure synthetic, pours like a 40 weight, protects like a 90/120 weight. enginE oil, to include Syn3 is too thin for a tranny!!! (The MOCO says it's okay, but they're WRONG!)

Primary= SYN3 or Mobil1 V-twin. Actually you could get away with conventional oil in there if your worried about clutch slippage, but alot of folks are running synthetic with no problems....I current am running SYN3 with no problems!

Engine. Mobil1 V-twin or SYN3. Big difference~Mobil1 is a 100% PURE synthetic, SYN3 is NOT!!!! Currently am running Syn3, but will switch to Mobil1 on next change.

GO TO THE OILS SECTION....THERE'S A TON OF INFO. THERE TO READ.

joe

 

All great info guys but you fail to comment on the roller bearing issue. I wouldn't use it for fear of flat spotting. anyways also any comments for my engine noise??

 

If you think its so slick to cause a roller to slip do ya really think itll make it flat spot. Donnie Peterson talked about this last fall I believe in AI. He thought it was and old urban legend.

 

Hummm,... I just cant see that happening, because there are too many racing professionals that use only synthetics, and racing is alot more extreme than your average Harley can dish out. I believe it is more of an urban legand than an actual occuring problem with synthetics. I guess that anything is possible but I would like to see some pictures of the flat bearings due to synthetic use.


John

 

I am getting my 1k service tomorrow, yes on the 4th of July. It is being done by a certified HD mechanic, who has offered his services on Craigslist here in the bay area. I am saving big time going through him and he claims to do more than what the Stealers do. Anyways, I am using Mobil One V-Twin oil. I have been using Mobil One on all my vehicles and I will trust it in my Harley! No offense to your chopper builder, but Mobil has their R&D and this is simply what they do OIL!. I have also check this forum on using Mobil One V-Twin Oil and everyone is recommending it. They claim shifting is smoother and the engine quieter and cooler. Just my .02 cents!

 

Kaduku are you using the mobile 1 in all areas. I had my first service done a month ago and went with syn3 and am not impressed. I have a hard time getting into neutral when warm, i am finding it harder to shift and at times missing second, and when the bike is warm the clutch is slipping. Dont know if this is all due to the syn3 but prior to the first service i had none of these issues.
Bruinx. I know that my bikes makes allot of suspicious noises and when i listen real hard it gets worse, i have come to see that these things make noise and have learned to become friends with the normal ones. I can become hypersensitive and think that the bike is going to blow up, but not true, keep your ears open for the bad ones and learn to enjoy the normal ones. As far as your friends advice, ive been to several different dealers and bike shops and to find two that agree on the same topic would be a miricle. As the old saying goes opinions are like A$$holes everybodys got one.

 

clayman,

I have to agree with you on that. At my 1000 mile service I had my steeler put the H-D syn 3 and formula+ in my bike and I have now noticed that every so often my clutch will slip. I'm not impressed at all with Harley's Synthetic oils. I now have appx 1,600 miles on my 06 Superglide and I think I'm just gonna go ahead and change all of the fluids in my bike within the next couple of weeks. I've gotta find me a service manuel first though. I'm gonna go with the Mobil1 V-twin 20w50 in the motor and primary and Mobil1 synthetic 75w90 gear oil in the tranny.


John

 

10800 miles on 06 dyna been using the dino oil from day 1 and the formula trans oil .runs good shifts great see no reson to use any other fluids.only complaint is it runs hot but just drop the oil every 2k for 3.99 hd oil