I did not find anything really specific at bobistheoilguy, just alot of semi-technical stuff about oil in general. Do you have a specific URL link to info that relates to this post?

And so you are using Mobile SuperSyn V-Twin 20W-50 for engine and gearbox?

 

Ya gotta do a little reading. There is a section on motorcycles, and while the references to HDs are few, there are many tidbits that relate to this topic, especially synthetics with friction modifiers and clutch slippage. There is a section on new oil analyses that has some relevant info in it, particularly the presence of friction modifiers.

After a short scroll through a few of the topics, it appears that:

Mobil 1 15w-50 car oil has some moly in it.
Moly is one of several friction modifiers.
Some riders using Mobil 1 15w-50 and other weights have had clutch slippage.
Others haven't had clutch slippage.
One guy had clutch slippage with Amsoil.

So the results are rather inconclusive as far as whether Mobil 1 car oil (hereafter known as "red cap") will cause clutch slippage. But as the latest version (SL) contains some moly it is probable that clutch slippage might occur, but not a definite. (Hey, would that statement qualify me to run for political office?)

Being the el-cheapo that I am, I'll probably switch back to using ATF in my primary at my next oil change. It doesn't cause clutch slippage and has that purty red color!

 

I understand the advertised benefits of sythetic oils and have used Amsoil in 1 car.
The car I bought came with a product guarantee, so what's to lose?
If you read the warranty and are comfortable with it's guidelines and clauses, it seems to be a win-win situation, given a drive train problem occurs within the specified time.

It so happened I worked in a dealership and had my car serviced to find transmission problems. The transmission was at a early stage of slipping... imagine that?
The Tech went through the tranny with a fine tooth comb. The synthetic fluids and additives contributed to the problem. It caused the seals to swell (which it's supposed too) to give longer life. Instead it actually caused premature breakdown of the seals, which in turn caused debris in the pan and screen, that caused etc...

Would I use synthetic's if a new car/scoot came with it... probably.

Will I use synthetics in anything else. Personally I chose not too.

 

Okay, then for a sporty 1200C, what would you recommend since from what I understand, it's a little different than the bigger engines?

 

Some think it's a wate of money, but I use H-D oil.

 

To tell you the truth most oil's are pretty good right now that's on the market todayand they all have some form of modifier's in them but you got to think if Im stuck in traffic and the motor get's pretty hot it's better to have syn. oilin because it will take the heat alot better and not breakdown as much.

 

I originally started using mobil 1 in my wifes xl1200 back in 96, but then switched to amsoil cause it was cheaper at the time and she swears it runs cooler. Eventually gave in and started using the same oil in my old shovel and now my new fx however i use the heavier amsoil gear lube for the tranny. Sporty uses the 20-50 all around. Been reading some good articles on this subject which makes me feel like I made the right choice on my own

 

Well poco I gotta hand it to you; being a cheapo and knowing what you are doing is cool. [8D]

For me, however, I don't mind the expense of Mobile1 v-twin SuperSyn for engine, primary and gearbox. It's simpler for me, and theory I should never have to worry if I am using the best oil or not.

I am not much of a mechanic and have yet to learn how to service the Harley, but I am looking forward to it. I just hope everything else about looking after the Harley isn't as confusing as buying the right oil! [&o]

 

Howartthou, then owning a Harley should be a most fullfilling experience for you.

When do you get your bike?

 

Here you go, are you ready? With this load of useful information you will be able to add 55cents to it and possibly, just possibly get yourself a cup of coffee. If you change your oil and fluids regular conventional motor oil will be sufficient. Is synthentic oils better, sure but how much better are we talking? On paper the slightest of number increases would recommend a product to be better. Is it worth the additional cost? Thats up to the purchaser. How many high mileage bikes do you own, have you owned, and do you create? Most people will never see any benefits to the additional cost in that they will never use the mechanical application to warrant such protection. Did you want that cup of coffee now?