/5 /6 and /7 Airhead Design Blunders

[Deleted User 62]

Ah, never say never. As I recall, the /2 has stacks in both wheels.

Good point. I'll never say never again.

Stacks in both wheels because the wheels were interchangeable front to rear?


Ken

Correct

Not so much of a problem with the /2 wheels because the hubs had steel sleeves instead of bearing to aluminum contact. I wonder why they made that change?

[Deleted User 62]

ME's best hit is the oil filter issue. That was a very stupid design.

Speaking of oil filters......

I think the changing designs of the oil filter housing that led to the $2000 O-ring would have to be right up there too.

Amen

[ME 109]

On a sort of related issue, reliability.
Over the years people have chatted to me when admiring my RS, talking about reliability.
Oh they're very reliable apparently, they say.
Reliable?! Strewth, there is nowhere left for me to go, I've pulled everything apart more than once.
I've had the gearbox out of that thing twenty times, no shit.
I say to them, oh yes, very reliable.
Mind you, it's only come home in a trailer one time.

[Roy Gavin]

Vincents also have stacked taper bearing in the hubs and no one complains about them - they are better engineering than a deep groove ball.

Apart from the side stand, and indicator switches, my main gripe is the frame. If you can find a photograph of the original McCandless designed Featherbed frame and compare it with the final version that Norton finally put into production there are several important changes,added braces, changes in the swinging arm mount details, etc,etc, but it seems that BMW copied the original version.

One reason modern transmissions bearings last longer is that they use "Sealed Clean " shielded transmission bearings, which have a service life three to five times longer than an unshielded bearing.
Rotax use them in them in their bullet proof 650 singles, but there seems little interest in fitting them to Airhead boxes.

My 1977 75/7 is still on the original valve seats, but I have seen a 78 bike with seats that has almost vanished, so it seems l not a design fault but a bit penny pinching.
Like the cheap and nasty Romanian bearings in the Oilhead boxes and rear ends------.

[Major Softie]

On a sort of related issue, reliability.
Over the years people have chatted to me when admiring my RS, talking about reliability.
Oh they're very reliable apparently, they say.
Reliable?! Strewth, there is nowhere left for me to go, I've pulled everything apart more than once.
I've had the gearbox out of that thing twenty times, no shit.
I say to them, oh yes, very reliable.
Mind you, it's only come home in a trailer one time.

To be fair, you can only compare the reliability of your machine to the other motorcycles of the time. What make do you think could equal the reliability of the Airhead? In the first few years of the /5, I don't think anything can touch it, but once the Goldwing came out, you would have to say the Beemer had some real competition - though still not in a lighter weight type of machine. Even today there are very few models from other manufacturers that are designed to go 100's of thousands of miles (even WITH the "maintenance" that yours has demanded).

[Major Softie]

Vincents also have stacked taper bearing in the hubs and no one complains about them - they are better engineering than a deep groove ball.

No, not better engineering. Better for side loads, such as are encountered with a hack, but not for 2-wheel riding.

"Better" engineering is that which makes the "best" compromises between cost, performance, weight, and complexity. The taper bearing stack sacrifices cost, weight,and complexity of assembly and maintenance, for sidecar performance. "Better" only if you have a sidecar.

[ME 109]

(even WITH the "maintenance" that yours has demanded).

'Inflicted maintenance' might be a more apt description.
Actually, other than my recent tranny rebuild which was after an exceptional (13 years, 100+k) service life imo, my bike has been behaving itself very well for about three years.
I haven't peened anything for ages, and I'm getting fidgety.

[melville]

Boy, I think there's a sidestand on my bike but I don't think I've had occasion to use it.











On account of it SUCKS!



I'm just a little troubled that the right rear wheel bearing is not accessible without pulling the whole darn stack. It seems they could have made the seal bore hole in the hub just a wee bit bigger, and then one could access the bearing for cleaning/regreasing for just the cost of a new seal.

[daz]

Ah, never say never. As I recall, the /2 has stacks in both wheels.

Good point. I'll never say never again.

Stacks in both wheels because the wheels were interchangeable front to rear?


Ken

Correct

Major, does that mean my /5 has interchangeable wheels as well?

[khittner1]

Was anyone with functional hearing involved in the design and testing of the RS and RT fairings and windshields?