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another airhead question: OIL

ultracyclist

New member
I am stealing this idea from the K bike thread.
Can you run synthetic in airheads?

For that matter, what happens when you put synthetic oil into a machine that has been using regular oil for years (1000's of miles)?

When is it dangerous to run synthetics in any bike?
 
I'd say it would be "dangerous" to put synthetics in a bike that has sat up for a number of years. Dried out seals will likely weep/drip oil if you put synthetic in it as part of bringing it back to life.
 
Depensds on the synthetic. The early ones were not miscible with petroleum oil, but except for some very high zoot hard to find exotic types "synthetic" and petroleum oils have been fully miscible. If the synthetic oil has a Mil.Spec. or has an API seal on the bottle it is miscible with petroleum oil.

Due to temperature variations in the purely air cooled engine, Airheads are good candidates for synthetic engine oil, if the engine seals are in good condition.

I am not aware of circumstances where it is "dangerous" to run synthetics provided the synthetic oil has the appropriate API rating, and is a proper viscosity for the the ambient temperatures and the specific engine. See your manual for those specified ratings and viscosities.
 
I put synth in my /7 which had sat for years, but it was hard to tell whether the leadage was from the oil or simply because the thang was a sieve to begin with. I'll be looking at both crank seals during my project, but I know that the oil pan gasket was bad, along with the pushrod seals...and there was a little oil weeping from the cylinder/block joint...

However, in general, I don't think you can go wrong with synthetic oil...if a seal or gasket leaks when you introduce synth oil to the mix, it needed replacement anyway, is the way I see it...I'm convinced that it is better for the engine, and agree with Mr. Christiansen about using it...

However, in my opinion, the VERY MOST IMPORTANT component of long engine life remains frequent service intervals...I use synth in all my vehicles, except the Harley, but religiously follow a 3000 mile interval in the four wheeled vehicles, and 2000 miles in the motorcycles...yeah, it's expensive, because they recommend that you take the interval out to like 8000 miles...but I gotta tellya, when I drain the oil, there's a lotta muck in there that just can't be good for the engine... So to me, the cost of oil changes is off set by long term reliability...although frankly, I never keep my vehicles long enough to take advantage of the long-term aspect of that!!!

The only reason I don't use synthetic in my Harley is because I haven't found a 50 weight synthetic that is convenient to buy in my area...the engine is based upon a shovelhead lower end, and the conventional wisdom for a shovel is to use straight weight oil..and the only synthetic oil available is 20-50w...so I err on the side of caution...although I've used 20-50w a coupla times...didn't hurt anything... but I've done some reading which has convinced me otherwise
 
Having that problem right now, Tranny in my 1970 r60/5 leaking like a siv because of synthetic. All who gave me advise even the dealer said never in an old bike, the dealer apologized for doing it they said it looked like it had synthetic in it. now I need a drain and refill to hopefully solve the problem.

Brett Endress
Altoona Pa
 
However, in my opinion, the VERY MOST IMPORTANT component of long engine life remains frequent service intervals...I use synth in all my vehicles, except the Harley, but religiously follow a 3000 mile interval in the four wheeled vehicles, and 2000 miles in the motorcycles...yeah, it's expensive, because they recommend that you take the interval out to like 8000 miles...but I gotta tellya, when I drain the oil, there's a lotta muck in there that just can't be good for the engine... So to me, the cost of oil changes is off set by long term reliability...although frankly, I never keep my vehicles long enough to take advantage of the long-term aspect of that!!!



too often. i know their are as many opinions on this as damn near anything in the motorcycle world, but that frequency of changing is just wasteful.

i'm a bit skeptical of anything over 6000 mile intervals in our motorcycles, 12K may be fine for a modern car running modern synthetic, but i wouldn't do it on a bike. i used to run my oilhead 6K on synth (a new qt every 2K didn't hurt). i ran the dino in my airhead 4K this summer, seemed alright (as in "shadetree alright" it smelled like oil and didn't have sticks or small animals or chunks of metal in it). i'm gonna switch to synth when i get around to finishing up replacing the rear seals.
 
Synthetic Oils . . . .

I have a business cleaning diesel fuel to rid it of water, algae and anything foreign to clean fuel. My business is limited to marine use.
I also am a dealer/distributor for Royal Purple lubricants.
Synthetics do a great job cleaning engines and eating sludge. They will clean an old gasket, pushrod tube seal or v/c gasket perfectly. Unfortunately sludge helps seal old gaskets. Your engine will probably leak if the gaskets and seals are old.
I have replaced most gaskets on my airhead. I still have to do the rear main seal. So no leaks.
The engine is quieter, it pulls better, I don't burn any oil and can go 5000 miles on a change and I know that I am getting better mileage. I know synthetics dissipate heat better. I use it in the engine, trans, fd and shaft.
Change those seals and gaskets and feel the difference!
Remember, the worst synthetic is better than the best dinosaur oil!
Campbell Tellman II
'93 R100RT
:thumb
 
In my tenure as an automobile mechanic I was particularly fond of the air cooled German cars. When Redline synthetic became available in the 70's we quickly adopted it. The older cars would start to leak. We learned not to suddenly switch an old car to 100% synthetic right away. The trick that worked was to introduce a small amout of Redline, like a cup. Then at the next oil change add a quart. Then at the next oil change say a 50/50 blend. The engines seemed to like this and I can't remember any car leaking once we adopted this approach.

Not to hijack this thread, but by the 1980's I was totally SOLD on Redline as we had enough experience with the engines we had built to show a lack of sludge, and improved bearing condition compared to the regular oils at the time.
 
Since rebuilding the 82, R100RS 4 years ago I have run redline synthetic. The only problem is at the cash register.
 
I am stealing this idea from the K bike thread.
Can you run synthetic in airheads?

For that matter, what happens when you put synthetic oil into a machine that has been using regular oil for years (1000's of miles)?

When is it dangerous to run synthetics in any bike?

It won't hurt anything but it will may have oil seepage. I tried it both on a K bike and my airhead. The K bike seeped at the rear seal and the airhead seeped at the push rod tubes. Neither leaked before I changed to synthetic and both stopped leaking when I switched back to dino oil. I sold the K bike but the airhead hasn't leaked in over 10 years since I switched back to dino. I'm a slow learner and should have learned after the K bike. Both bikes had 40,000 +- miles and were between 10 and 15 years old when I made the switch.
 
I put Amzoil for motorcycles (20W50) into my airhead as soon as I got it home. I've had no leaks.
 
I changed to Amsoil soon as I got home with mine, too. No *new* problems with seepage. The rear seal was already leaking. I've since had the transmission reworked, and so I replaced it along with the oil pump o-ring.

Last weekend, I changed all the fluids after 4000 miles; I'd added less than a cup to the engine between changes. The oil was still fairly clear, which I felt good about, and the drain plugs on the transmission and FD had very little of the fine paste on them. I'll keep using it.

Tom
 
Prior to the Airhead I'm on now I owned three K bikes --

1987 K100RT bought in 1996 with, as I recall, 76,000 give or take a few miles on it. I switched it to Mobil 1 at the first oil change. No problems.

1995 K75RT bought "as new" in 1998 with 1,150 miles on it. I waited until the 6K service and switched it to Mobil 1. No problems.

1995 K1100LT bought in 2002 with just over 20K miles on it. It had already been on Mobil 1 since 12K. No problems.

Before I forget, I also ran synthetic oil in the transmissions and final drives.

I've owned two Gold Wings (still have the second). I ran Mobil 1 in the first, and am running Shell Rotella T synthetic in the current Wing. Synthetic oil in the final drive. Neither used oil or had any clutch issues (wet clutch in the Wings).

The Airhead (acquired in October this year) is on Mobil 1 and it does not have any leaks. I just looked and it is showing 19,724 miles on the odometer. It probably would have been good to finish breaking it in before switching to a synthetic! :ha

Seriously, the PO rode around 1,200 miles a year and changed the oil and checked the valves once a year. The bike has not been mistreated and has in fact been pampered.

While I read of folks who go up to 8K between changes with synthetic, that is just more than I can accept. So I change the oil on 5 K intervals or once a year in the fall -- whichever comes first.

And while I'm thinking about it, what is the valve adjustment interval for the R100 series?
 
Remember, the worst synthetic is better than the best dinosaur oil!
Campbell Tellman II
'93 R100RT
:thumb

I dunno about the very worst synthetic on earth, but any good quality synth (don't get me going about Redline, I LLLLOOOOOOOVEEE that stuff!) is gonna be better than just about any non-synth you can lay hands on.

Use synthetic. Change on dino intervals. Oil is relatively cheap, even at $11 a quart. Our bikes are precious. Or at least, MINE ARE.
 
I dunno about the very worst synthetic on earth, but any good quality synth (don't get me going about Redline, I LLLLOOOOOOOVEEE that stuff!) is gonna be better than just about any non-synth you can lay hands on.

Use synthetic. Change on dino intervals. Oil is relatively cheap, even at $11 a quart. Our bikes are precious. Or at least, MINE ARE.

I completely agree regarding the interval... Nothin' worst than dirty oil, don't care what it's made out of!!
 
Yes to synthetics for airheads...

I use Mobil-1 15/50. This was suggested by my factory-trained BMW mechanic.

No issues to date.
 
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