Diggerpine here; I use Mobil 1 V-Twin 20-50 Synthetic in my motor, Dextron VI Full Synthetic Automatic Transmission Fluid in my primary and Valvoline 75-90 Synthetic in my tranny.

In answer to your questions: (IMHO)

#1 Depends on your preference. I use 20-50 to cover all temperature ranges.
#2 I don't have a problem with my clutch (a wet clutch system is a wet clutch system)
#3 V-Twin is for motorcycles, Regular M-1 is for cars.
#4 After changing out the fluids and taking the bike out for a short run to warm everything up I would change out the engine and filter and primary oil to get rid of any conventional oil still in the system. As far as the tranny goes, as long as everything drained out, and the synthetic is in, I would leave it alone. (IMO)

My oil temp usually runs about 175-180,(in the breeze), hottest I've seen it in 100 degree weather is 210. Idling in stop/go traffic maybe 220/225. My primary runs quiet and clutch shifts smooth and I can find neutral very easily.

Ride Safe!
Steven

 

For a stock bike, I would run the syn3 from Harley in everything. 1 fluid makes it simple. If your doing it yourself, it makes it simple to stock the fluid in your garage. I also purchased a scavenger oil change system, and it helps to get all old oil out, so you don't end up mixing your new fresh oil with the old oil that gets left behind. (I always hated that) but I have a Softail, your Ultra could be a little different.

 

Amsoil. You can run 20-50 in all three holes. 5000 mile change out.

 

1. Primary you can use Mobil 1 V-twin 20W-50. Tranny use a gear oil not an engine oil, 75W-90 would do Mobil 1 if you can find it.

2. I run Mobil 1 V-twin 20W-50 in my '09 Ultra with no clutch problems for the last 4000 miles. Although others have warned there have been problems where the engines been modified.

3. There is a difference in that V-twin has been formulated to run in wet clutch systems. I have read of those that run Mobil 1 15W-50 in their engines with no problems but definitely not in the primary. The differences may be so slight that your engine may not see the difference unless your running extended drain intervals.

4. When you switch to synthetic, just do your next service a little earlier than you normally would since the synthetic will to, some extent, take on the properties of the conventional oils. No need to waste fluids.

Enjoy the ride.

 

I searched threads for a while and didn't come up with much...

You're kidding right. Did you go to the oil and lubrication section. There are 6 years, 8 months, 3 days and 9 hours worth of reading on just that subject.

 

@gree: There's enough information there to make your head spin...

 

Look in the oil section this is old stuff. Mobil 1 syn 20-50 in engine and primary, mobil 75-90 syn gear in tranny. runs perfect.

Harley does not make oil they just put their name on it.

 

I run the Mobil 1 synthetic 20W50 in motor and primary and the Mobil 1 synthetic gear oil 75W90 in the trans. Shifts smoother and quieter. Guys with oil temp gages report 10 to 15 degrees cooler with Mobil 1 than with the Harley Syn 3 which stands to reason. Syn3 is a blended synthetic, Mobil 1 is a full synthetic. I run a K&P Engineering oil filter (filters finer particles than Harley throaway and has pressure valve like factory, but I can wash out the element and inspect for particles, also it serves as a heat sink to help cool the oil that goes through it). I still change oil and clean filter at 4K and service chaincase and tranny every 15K. Service is the life of anything mechanical. Take care of it and it will last a long time.

 

Oil is some high tech stuff developed at a molecular level. It's all about the additives.

I use Mobile 1 V-Twin 20-50w in the engine (made for aircooled)
Redline V-Twin Primary Case Oil
Redline V-Twin Transmission Oil with ShockProof.

Yes you could use the same oil in all holes and get by. But, why would I put engine oil in anything but my engine ? I don't what or need additives that encapsulate soot in my primary. I'll leave room for what's really needed. Get oil specifically developed for the application.

Just my opinion.

 

I run Mobil 1 Vtwin 20w50 in the engine, Mobil 1 4T 10w40 in the Primary, and Mobil 1 75w90 in the Trans. I have 34000 mile on my 08 Flhx and never had a problem..........

 

I'm going to try the 4T 10w40 in the primary on the next change.
http://www.v-twinforum.com/forums/engine-oils-lubrication/155026-info-mobil-1-a.html

 

I use Mobil 1 V-Twin 20-50 Synthetic in all 3 holes and change every 5000 miles.

At 30,000 miles with no problems relating to lubrication at all!

 

I am thinking about going this route. Harley dealer says use thier 20-50 syn all three holes so why not go to wallmart and get Mobile 1 V-twin by the gallon. Prob the same stuff anyway.

 

I run 20-50 amsoil in all 3 holes no problems

 

I searched threads for a while and didn't come up with much...

You must have found some obscure forum to search because every one I've been on has more info on the great oil debate than most would care to know.:beatdh:

All Amsoil Synthetics here. Search for George Douglas if you want Amsoil.
Amsoil 20W-50 in the engine
Amsoil Supershift ATF in the Primary
Amsoil Severe Gear in the tranny.

 

I'm going to the new blend HD has now . HD in the Primary and Bel Ray in tranny .

 

I keep seeing Mobil 1 V-Twin Syn Oil mentioned. Where can this oil be bought. I just have not seen any. Thanks for your help, trying to wean off the $12/qt. HD Oil.
Leon

 

Motorcycle shops, Autozone, checker ect ect

 

Amsoil 20/50 in the engine and the primary, and 75/110 in the Trans. Change primary every 10k or once a season, change tranny every 20k or once a season and the oil every 5k.

 

There is no problem with using Mobil 1 or Syn3 or Amsoil (or other quality synthetic oils) in all three holes. It's just that it is quite expensive to go that route. Air cooled engines depend on their oil for a lot of cooling and need it to maintain its lubrication and cleansing properties through a very broad temperature range. This requires a top quality oil to accomplish this. However, the primary and tranny don't need near the quality of oil in them that the engine requires. An oil good enough for the engine is certainly good enough for the primary and tranny... but probably also an overinvestment.

 

I run:
Mobil 1 20W-50 in the motor
Red Line MTL in the primary
Red Line Shock Proof Heavy in the Tranny

I see that Red Line now makes V-Twin specific oils to use instead of the MTL and Shockproof heavy....I may pick those up when my current stash runs out.

 

royal purple 20-50 max cycle engine
royal purple 75-90 trans
royal purple max atf primary

but that's just me. Have tried lucas v twin 20-50 in all three also and all was good.

 

1. What is a good weight for primary and transmission fluid? I ride in weather ranging from 45-90 degrees F (Ohio). The owner's manual simply recommends "Harley" products and does not give weights.

Any 85w140 or heavier synthetic gear oil works well in the 6-speeds. Redline Shockproof Heavy is a favorite that gets good reviews, and I'll second the vote. I have also used Royal Purple 85w140 and it works equally well, as should any name-brand gear oil.

2. I have heard that synthetic is not a good idea for the primary due to issues with the clutch. The bike is completely stock, is synthetic a problem?

There is no need for using synthetic oil in the primary. I use an inexpensive 20w50 fossil engine oil and it works very well. Some use ATF with success, but if the oil is too slick and heavy with friction modifiers it may cause the clutch to slip. I would stay away from moly as an additive, excellent for engine but to be avoided for the primary IMO, and most synthetic engine oils contain moly.

3. Is there a difference between Mobile 1 V-Twin and regular Mobile 1?

Very little except for price. Mobil 1's 15w50 is $23/5-qt. jug at Wal-Mart and is a bargain. Three MC mags have tested oil and this one is always a standout, with an additive package very similar to the V-Twin variant. Many HD riders use it without issues. A friend recently tore into his 2000 TC88 for a big-bore upgrade and found no visible or measurable wear to pistons, cylinders, or rocker components at 60k miles. He's used the M1 15w50 for the duration. Another bike was also upgraded, this one with 50k and had been using Amsoil 20w50. The components were indistinguishable between the two bikes, and there was also no sludge at all. I don't need to tell you which oil was more expensive.

4. Finally, and most important, should I change the engine filter and flush all three systems to get all the conventional oil out (I mean changing the oil twice to get rid of all the old conventional)?

No need to do that. All engine oils are compatible and the small amount that remains won't hurt anything.

 

Question? Im coming up on my 1000 mile service. Go to synthetic or (been told) wait until 2500 miles before putting synthetic in the bike. (09 EGS)

 

As always,everybody has a different opinion.Good Luck in your experience,you certainly don't need mine.

 

I run Red Line Oil, all synthetic in my '04 Softail. 20W50 in engine, their MTL in primary, and Shockproof Heavy in the tranny. All work well for me, engine runs cool and quiet. Shifts are quiet too. Red Line is a bit harder to find but I order mine directly from Red Line.

 

WIth all the debate, opinions and recommendations here I could not make up my mind. So I mixed Amsoil, Red LIne, Royal Purple, Mobil 1 and Spectro all together. I figured now I have them all covered and nothing should go wrong because I use all the good synthectics. JK......just use any good oil whether dino or synthectic and change it as needed.

 

I hate the Syn3 harley oil. I have since dumped the Harley Syn 3 for another brand and will never go back.

The engine was much noisier when warmed up, oil pressure dropped way to dramitically with the Syn 3 and the engine ran too hot for my liking. Syn 3 might be ok for 50 degree days but once the temps get higher outside then it turns to water.

 

Spectro 75-140 for your transmission. Made specifically for 6 speeds trannys. Give it a shot, you won't regret it.