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When to use synthetic

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Old Jun 16, 2007 | 04:28 PM
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Default When to use synthetic

OK I know this has probably been discussed before and is a very subjective thing but when should I put in synthetic oil? All the jap bike people tell you 5000 miles. On the HD forum people seem to be putting it in at 1000 miles. Do the Harleys break in faster? And one more time, I am going to use Mobil One. What do I put in the engine, tranny and chaincase? T.
 
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Old Jun 16, 2007 | 04:44 PM
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Default RE: When to use synthetic

I changed to synthetic the day I took delivery. My selection in each hole has changed and I'm finally settled on Mobil I V-Twin 20-50W Syn. in the crankcase, Redline MTL in the Primary, and Mobil I Full Syn GEAR oil 75-140W in the tranny.
 
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Old Jun 16, 2007 | 06:38 PM
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Default RE: When to use synthetic

At the 1000 mi service my dealer put HD 50 wt in engine, HD formula+ in primary & tran. At 3400 mi I changed to Mobil 1 20/50 in engine and primary, Mobil 1 gear lube 75/140 in tranny. This Mobil 1 iswhat I plan on using from now on. I would have no problem putting the synthetic of your choice in at the 1000 mi service.

07 FLHTCU
 
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Old Jun 16, 2007 | 06:43 PM
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Default RE: When to use synthetic

I have all synthetic sitting on the Shelf waiting to go in my Street Glide, I haven't even started it yet,And Am doing a 107.9" in a couple weeks..It'll be in there for the first fire.
 
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Old Jun 16, 2007 | 06:48 PM
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Default RE: When to use synthetic

Ultrasweet, lets use some logic here. Now think about it for a minute. Why would you have to wait to put synthetic oil in an engine? Synthetic is the same weightoil with additives. You can put it in from day one. The reason people wait is because why drain out perfectly good oil. I find it so hard to believe all the oil issues.For many many years, everyone used regular 20-50 oil and the engines were fine. Way too much hype on oils. Change it regular whatever you use and your engine will do just fine.
 
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Old Jun 16, 2007 | 07:53 PM
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Default RE: When to use synthetic

I am not an old Harley guy. My book says there is engine, tranny and chaincase. Is the chaincase and the primary the same thing? T.
 
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Old Jun 16, 2007 | 09:28 PM
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Default RE: When to use synthetic

Yea Ultrasweet....the chaincase and the primary are the same. Be carefull what you run in there because the clutch is in there also. You'll be safe to run a regular non-synthetic 20-50Win it. Then You have the transmission. Mine was so noisey, I ended up running that Redline Heavy in mine to help quiet it down. There are so many choices out there for the transmission. Run something at least a 80-90W or above. Belray has something like a 85-140W that is good.Then in the engine, use a 20-50 of your choice. You'll have 3 different things to change...Engine, Transmission and primary.
 
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Old Jun 16, 2007 | 10:58 PM
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Default RE: When to use synthetic

Well,
I did not start this thread, but I did glean some valuable information anyway.
I took mine to the dealer for the first change. I was told I had to for the warranty. They did it for free though.
However, I never plan on taking it back. I am convinced that the dealer I purchased mine from (nameless intentional)has no business working on a bike. They never even lubed the cables although showed that they did on the paperwork. it also had oiley handprints all over the seat and engine guard when I picked it up.
Anyway, thanks for the info!
Rick
 
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Old Jun 16, 2007 | 11:02 PM
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Default RE: When to use synthetic

I think you've gotten good advice. You can change at any time. I went to Syn 3 at 1000 miles because you don't change all 3 holes, and because I hadn't found HD Forums and all this great info.

I use Mobil 1 Synthetic VTwin in the engine, Mobil 1 Synthetic Gear 75-90 I believe in the tranny and Mobil 1 Synthetic VTwin in the primary. I think that causes a little issue with the clutch and may use Formula + in the primary moving forward. Most of my buddies that are serious about their bikes are doing similar things.

I have more than 130,000 miles on my Nissan Pathfinder, I've changed my oil using Mobil 1 Syn since new every 5,000 miles. Runs light the day I bought it, never had an engine issue.

I'd just as easily use the Amsoil equivalents, I've heard very good things.
 
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Old Jun 16, 2007 | 11:31 PM
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Default RE: When to use synthetic

I'm going to open up a can of worms here. ATF Type F works best in the primary, your clutch will love it.
 
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