• First of all, you've got to understand that almost all tires sold are now tubeless. As such they seal at the inside surface of the tire (the portion of smallest dia) and not at the bead. What this means is that all modern tires are now probably 0.060" to 0.120" tighter at that area of smallest dia. As opposed to the OEM tires fitted in 1980. 

• Now look at the portion of the rim between the beads... the portion that's hidden when the tire is fitted. On my 1979 model bike, that portion was roughly cast and NOT machined. You won't find a modern cast wheel that doesn't have that surface finely machined so as to make perfect contact with the tire and allow an air-tight fitment for tubeless service. 

So it's the fit between the larger wheel OD and the smaller tire ID that makes fitting the tire so difficult. Measure it yourself. On a 19" wheel that surface should be glass-smooth and turned to a dia of 19.000". On a rear wheel, 18.000". I bet your front wheel is 19.120" or more! The numbers won't lie.

IDEAS

1. Good. I'm glad you're using tire lube and not something worthless, like WD-40. You might try another brand. Ask your LAPS for some "professional tire mounting lube". One thing for sure, don't skimp on the lube; lube both the rim and the bead of the tire. Work quickly and inflate rapidly WITHOUT the valve core installed. I've had to take mine as high as 65psi to get both beads to pop out. It's definitely a dangerous job. My rear tire was much easier to fit than the front.

2. Better. Go tubeless. The wives-tale of "casting porosity" is just that, but if you're worried then you can buy "mag sealer" and paint the inside of the rim. If you're having this much trouble in your garage, then you'll never be able to repair a flat on the open road ! Going tubeless means you can fix a puncture with a pug, in minutes, on the bike, and get more mileage from your tires. So there are distinct advantages. I ran mine tubeless, you would not be blazing 'new trails'.

3. Best. The optimal solution is to bring your wheels up to modern specs. Find a local machine shop that has a "gap-bed lathe" that can turn 22" (11" swing). Take the wheel AND axle to them. If they turn the wheel on the axle, then the cut will be concentric. Have them re-surface the tire seating area between both beads to the precise dimensions, while maintaining the original corner radius. The cutting is child's play. Any high school machine shop grad could grind the bit and make the cut. The hard part is finding someone with a gap-bed lathe that's willing to stop making $200 per hour parts for a 1-time home project. 

Hope this helps.

An addendum to Idea #1...

There is a super slick rubber seal installation lube called P-80. If you ever install fork, gearbox or crankshaft seals, then you'll need this stuff. It would not be good tire mounting lube by itself due to evaporation issues, but it might enhance your existing tire lube. 

Just an idea.

Richard Whatley, thanks very much for the insight and advice. I will try your suggestions and I’m glad to hear positive report on going tubeless.

much appreciated!!

One of our members here in IL lives fairly close to me and has a tire machine. I took a new tire and rear wheel by his shop and the first thing he asked me was "is it a Michelin?"  Michelin tires are reputed to be difficult to seat for the reasons Richard disclosed earlier. 

There are some people who advise against going tubeless on snowflake rims due to the profile of the casting where the bead of the tire seats. I only ever owned 1 Airhead with snowflake wheels, and always used inner tubes. I have never run Michelins. Some owners, myself included, dust the inside of the tire with corn starch reduce the friction between the tire and tube.  The highest pressure I have had to apply to a tire was slightly more than 100lb/psi. In that case it was a front tire for my R75/5. I left the tire/wheel outside in winter to chill it down and then set it up on a low prop and lit up a kerosene torpedo heater blowing on the part that wouldn't seat. Then I walked away for a few hours. When I returned, the tire was seated nicely all the way around. 

Do you know of anyone with an empty chest freezer? Blow that puppy up to 100lbs, freeze it for a few hours, and then lay it out in the sun, and walk away.

Thanks for the info James.

I wish I had known that about Michelin before I had bought these tires.

I’m curious to hear opinions / experience on what tire, brand / model (currently available) that seem to be easiest to mount on the snowflake wheels.

I ran all sorts of brands of tires on my 1979 RT with snowflakes until I settled on Bridgestone BattlAx. Never noted anything super weird about the Michelins over the others. And I hand mount all my own tires. 

I enjoyed Airhead snowflake mags for many years and miles, 1981 till the late 1990s. Changed all tires myself, usually in a driveway with large screwdrivers. Tried several tire brands, and eventually gravitated to Dunlop Elite on the rear, but no preference on the front. Every tire was a struggle to mount, regardless of manufacturer. After mounting, I'd take the tire and wheel to a local gas station for access to high air pressure. Yes, I damaged a few tubes in the process; either pinched by a screwdriver, or by mega PSI required to pop the tire onto the rim. The only tire & rim combo I have found more difficult to mount than snowflake, is a 'run flat' car tire on the rear of a GL1800 Goldwing. The first one defeated me and my son, working together, but I have since learned a few tricks and mount them alone, at home, using a Harbor Freight (manual) tire machine.  

The long forgotten advantage of snowflakes is their safety aspect; if you ever have a blowout at speed, the tire WILL stay on the rim at least long enough to pull over, and usually much longer. I once limped a front flat, in the emergency lane, in 1st gear, for maybe a mile before it finally came off. On another occasion, I limped a rear flat for maybe 300 meters before it came off.

If I were mounting a tire on a snowflake today, I would NOT install a tube, would liberally slather 'No-Mar Tire Lubricant' on the tire bead, and wheel to include the middle recess. But after install, and before inflation, I'd wipe as much or the lube off as possible (it is so slick the tire will actually slip-rotate on the rim, under heavy braking). Even after wiping, there will be plenty of film remaining to still the tire pop onto the rim.

Good luck!   

As I said above, even 40+ years ago mounting tires on snowflakes was challenging. I believe snowflakes were designed specifically for safety, and recall them being touted as such, back in the day. I do not believe they are a mismatch with todays tires, therefore needing modification. With modern tire lube, they will likely pop onto the rim without the scary high PSI required without it. I would toss the Ru-Glide though, and use No-Mar. I say this because, with the Goldwing's rear car tire, Ru-Glide was no help, but No-Mar was a game changer. (Just don't forget to wipe it off.)  

Tubeless tires on snowflake mags have been a item of contention for a long number of years.

The "old wives tale about casting porosity" is NOT the reason tubes are installed in tires mounted on snowflake wheels despite the tires not needing them.

BMW many years ago stated the wheels were NOT to be used without tubes due to the design of the wheel and the ability for the wheel to hold a tire on during a puncture.   

If you run tubeless tires on snowflake wheels without tubes fine, that is your decision, but remember on the pre 85 wheels, BMW never recommended it.   St.

Hi Steve, I get your point on factory recommendations, but MC riders are risk takers by nature, and often rebellious and resistant to following instructions. I recall when, in order to make a Harley "chopper", we simply 'chopped' off everything we thought unnecessary, and/or weight saving. While at it, a simple mod allowed install of a Sportster front end on a 'big' Harley, which many others opined was dangerous. Only later did Harley begin to follow suit, and eventually offer 'factory choppers'. Similar with Honda Goldwing makers, who have always expressly prohibited sidecars, trailers and car tires, yet thousands of riders install any or all the above, and millions of miles have been logged, safely and reliably. Along those same lines, regardless of what BMW recommends, if I were ever to own another snowflaked Airhead, would probably give tubeless a try. 

I sure would like to have just one more snowflaked Airhead before getting too old, but the current mono shock 95 R100RT has spoiled me, and not sure I could make myself go backward in technology. Btw, another trick in mounting difficult tires on MCs, I forgot to mention above, is to first lay the tire out in the sun a few hours, so it gets more soft and pliable.

Thanks Steve 😉   

Sometimes the odds work in our favor sometimes not.  

I don't like it when someone talks about going tubeless on airhead wheels without presenting the facts.  

If a person has the facts at hand, understands them and chooses to make a decision one way or the other fine.  Thank God we are free to choose.  St.