Rob North racing airhead sale

[Garnet]

[quote="ME 109"]So what is with this airhead setup? Is it standard?

Well used?

[Deleted User 62]

So that was a car shock, right? Is there any specific information on why riders liked the twin shock bike better? Was the twin shock based on the same frame?

Chuey

If it is a car shock, I can't imagine it working to its full potential in a horizontal position. I would assume the damping would be less than optimal, unless the shock was specifically designed to work in that position.

[Deleted User 62]

So what is with this airhead setup? Is it standard?

Well used?

I think he is referring to the zip tied zip ties. (I like it!)

[vanzen]

So that was a car shock, right? Is there any specific information on why riders liked the twin shock bike better? Was the twin shock based on the same frame?

Chuey

My research indicates that the shock was originally an automobile item,
and also that the shock's performance characteristics were not as well suited to the bike
as the twin-shock arrangement.
Gietl was a proponent of the new mono-shock technology
and implementation would have involved significant trial and error ...
Error seems to best define this stage of development.

The same Rob North BMW-frame design,
which was closely modeled after his successful Triumph "low-boy" frame,
was used on all 3 original North-BMW F-750s.
Udo Gietl introduced and experimented with the mono-shock arrangement
and I would suspect that any or all of the frames were subject to his experiments.
Stretching the rules to the breaking point, a mono was also used on Gietl's R90S Superbike.
Shock relocation had been legalized to oblige Kawasaki,
and legend has it that Gietl responded that the BMW's shock had been relocated –
to a shelf in the garage.

Of the 3 North F-750 BMWs, Gary Fischer's twin-shock was converted to a mono in 1975.
(now in the Barber Museum),
Reg Pridmore wanted nothing to do with the mono and his remained a twin-shock
(in the collection of Even Bell, Irv Seaver Motorcycles) ...
and then there is the Lufty once-owned bike.
The e-bay ad copy that makes the claim "the only North-BMW mono" – misinformation, IMO.

If it is a car shock, I can't imagine it working to its full potential in a horizontal position. I would assume the damping would be less than optimal, unless the shock was specifically designed to work in that position.

Theoretically, the position of a shock will be of no consequence to the ability of the shock to work,
and although it's progressive characteristics will depend upon specific geometry,
more likely the downfall of the F-750 mono was a fault of spring rate, damping, or rebound choices.
Bear in mind that shocks of this period were not readily tunable / adjustable -

So what is with this airhead setup? Is it standard?

For a very short period of time, Luftmeister sold a "mono-shock conversion kit".
Short lived and very rare –
Perhaps because Lufty was not able to sort out a suitable shock as well.

Back in the day, Lufty marketed "boot-leg kits"
that emulated, at least "visually", virtually every technology that worked on the track.

[ME 109]

For a very short period of time, Luftmeister sold a "mono-shock conversion kit".
Short lived and very rare –
Perhaps because Lufty was not able to sort out a suitable shock as well.

Thanks Vanzen, I saw that bike at a rally last year and thought it may be of some interest to you guys. Sorry about the huge photo, if yez right click on the image and select 'open image in new tab' it will reveal a lot more bike.

[Matt]

http://boxerworks.com/main/
did y'all see the Ebay auction with the Rob North Luftmeister race bike?

[Deleted User 61]

You have been missing it, Matt!

http://boxerworks.com/forum/viewtopic.php?f=1&t=1340

Oh sure, merge your post with this thread, without saying anything and make me look silly!

[Chuey]

[quote="vanzen@rockerboxer.com"]

Reg Pridmore wanted nothing to do with the mono and his remained a twin-shock
(in the collection of Even Bell, Irv Seaver Motorcycles) ...

He had that bike in the shop for a while a couple years ago. I spent a fair amount of time looking at it. Man, it's cool.

Chuey

[Garnet]

make me look silly!

Do you need help????

[Garnet]

So what is with this airhead setup? Is it standard?

For a very short period of time, Luftmeister sold a "mono-shock conversion kit".
Short lived and very rare –
Perhaps because Lufty was not able to sort out a suitable shock as well.

Back in the day, Lufty marketed "boot-leg kits"
that emulated, at least "visually", virtually every technology that worked on the track.

Could that be what's on this bike?


Sorry, I don't have a better ic handy.