Welp, I went and did it. Put synthetic oil in the Airhead

I've read the threads, glommed over the success and horror stories, chewed all my fingernails off and with shaking hands ran my credit card across the terminal at O'Reilly's and walked out with two quarts of Royal Purple. I dumped out the old and put in the new fangled stuff and held my breath as I fired the old Putzfrau up. No leaks. It probably would happen that fast anyway although she did get HOT as I synched the carbs after finding a niftier route to the controls.

Afterwards, I went for a 300 mile run, half freeway at up to 85 miles per, the rest twisty heaven with almost deserted roads along Mt. St. Helens. (HWY 25 is open all the way now, unlike my attempt 2 weeks ago.) Reminds me of why I kept the tutonic twin, it ate up the choppy road sections with minimal protest. But you have to know how to ride these old girls, like a stubborn German (redundant?) they don't like to change course while fully committed to a challenge.

I replaced the main seal not long ago but the pushrod seals and most others are at least 15 years old. But still no leaks!

[spartanman]

Any noticable performance bumps? More power? Cooler running? Quieter valve train?

I've been pondering synthetic for my R100RS when I get it back on the road, but the seepy seals issue has me on the fence. Good to hear no leaks, so far.

Originally Posted by Jasper ST4

I've read the threads, glommed over the success and horror stories, chewed all my fingernails off and with shaking hands ran my credit card across the terminal at O'Reilly's and walked out with two quarts of Royal Purple. I dumped out the old and put in the new fangled stuff and held my breath as I fired the old Putzfrau up. No leaks. It probably would happen that fast anyway although she did get HOT as I synched the carbs after finding a niftier route to the controls.

Afterwards, I went for a 300 mile run, half freeway at up to 85 miles per, the rest twisty heaven with almost deserted roads along Mt. St. Helens. (HWY 25 is open all the way now, unlike my attempt 2 weeks ago.) Reminds me of why I kept the tutonic twin, it ate up the choppy road sections with minimal protest. But you have to know how to ride these old girls, like a stubborn German (redundant?) they don't like to change course while fully committed to a challenge.

I replaced the main seal not long ago but the pushrod seals and most others are at least 15 years old. But still no leaks!

I can't honestly say that there is any performance difference. My motivation was that I've used Castrol GTX all along and recently discovered they changed the formula (mostly dropping zinc, I think) to cooperate with cataclismic converters and no one locally stocks Golden Spectro 4 in the right weight. The Honda shop had it in 10w-40 and the parts guy said he uses it in his airhead. He also said that they all leak at every gasket. God help those Honda folks.

[Beemerguru]

Been using Mobil 1, Motul, and Redline for years in rebuilds after the rings set in. Never an issue with seals leaking or weeping. The new versions of all the seal aren't affected by synthetics.

[east high]

Dino vs. Syth aside, I've heard that whatever you run it should either come with zinc in the mix or you should add some when you change the oil. Old machines, like airheads, that have solid tappets need zinc in their diet to prevent pitting.

[Uncle Ernie]

Self-destructive tendencies run amok...

You're going to hell. Too bad.

[bmwloco]

I run synthetic in my '83 R100RS with no drama. I would run it in the '66 R60/2, but it dribbles out; put in dino juice, no dribs.

So far, so good. I go 6k between oil change and valve adjustments. Works.

Originally Posted by danedg

Yes...We're all going to Hell......sometime.
In the meanwhile, EastHigh is correct that most modern shit has not enough zinc to protect flat tappet lifters/cams...
The answer?
A coupla ounces/ oil change will protect your tappets. Doesn't matter what you use...put it in!

Hmmm, dunno about that. Too much zinc accelerates wear as well.


http://www.royalpurple.com/faqs-motor-oil.html
Do your motor oils contain zinc and phosphorous?

Yes. All Royal Purple engine oils contain the zinc/phosphorous compound zinc dialkyl dithiophosphate (ZDDP) and are suitable for both roller and flat tappet valve trains.

[durtwurm]

As they say, any oil is better than no oil! A lot of airy heads are using syn. without a problem. It is after all petroleum in part. My understanding is it stays on the moving parts longer and better. Personally I use Castrol MC oil because it's cheaper and well recommended by many including myself!

Originally Posted by danedg

Please continue to chew your fingernails.....

Hey, were did your post go? No need to get snippy about it. Adding the zinc is probably a good idea unless it's already up to snuff.

[Reposado1800]

Royal Purple is great oil.

[jdiaz]

When you think about the crap oils these bikes were developed to run on, Castrol GTX is just fine.

[Hawk Medicine]

Originally Posted by Clayjars

Royal Purple is great oil.

I run Dino in my Airheads mainly because with synthetic they leak like a sieve but we run Royal Purple in all of our cars and trucks and it's definitely a step up from whatever else I've tried. (Castrol, Mobil-1, etc.)

Honest to God... Our S-10 runs 40 degrees cooler, actually performs better and mileage is a smidgen better too. It still uses oil but at least I don't look at the temp gauge in the summer and have a heart attack! Same thing for my 89 Bronco-II. Another advantage is that our oil change intervals are now once every year to 15 months. We could get more out of it but I worry about contaminants since most of our driving is "local trips".

when I get around to trying Synth in my new Airhead engine, you can bet that it'll be Royal Purple!

[P B G]

Originally Posted by Clayjars

Royal Purple is great oil.

That's been what I've used in my e30 bmw car, for the engine and transmission, been meaning to put it in the differential as well, but put a mobil product in it about 8 years ago, and really i'm lazy about that.

I like it, I don't know if RP/Amsoil/Redline/mobil/whatever are really better/worse.

But for the airhead I most recently have been using Kendall GT, not going synthetic till I reseal it, weapy pushrods already.

[east high]

I can't remember what I'm running currently, but I'm gonna try this stuff out for the next oil change. It's going in my ol' 67 Rover too.