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Airhead Restomod

srq.fl

New member
As I begin the process of searching for my first airhead I've enjoyed seeing the restoration work to return these beauties to their original condition. I've also noted that detailed discussion of at least the middle years, say 70's and 80's airheads often point out the various practical limitations of components like brakes, suspension and electronics compared to newer technologies.

After watching many years of Barrett Jackson auctions where 60's and 70's muscle cars were restored cosmetically but with updated suspensions, brakes and often engines, so called "RESTOMODS" I wondered what "new" technology could be added as part of a restoration to accomplish similar performance improvements.

Now...I fully understand that this is NOT the same as restoration to "as new but original" and my purpose in posting is not to start a debate of the merits of restoration vs restomodding. My primary purpose is simply to understand:

1. Which components "could" be updated from a physical and practical point of view? Please give specific product recommendation for the components you'd replace if possible.
2. What, in order of importance, given #1, would be the things this forum's users feel would be the priorities
3. How cost effective would these improvements be vs restoring "as originally new"

Let me also state that engine/powertrain aren't my initial thoughts in this post. I have seen discussion elsewhere about carburation and cams and am happy to hear about ideas, and again be as product specific as possible, in these areas but its primarily the other matters that prompted the post.

Thanks in advance for the education I'm sure to get.

Randy in Florida
 
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I would suggest you consider upgrading the electrical charging and ignition systems...

The wire wound rotor and diode board were not even state of the art when the bikes were new, I would
suggest that a failed rotor is one of the most common faults with an airhead. Its happened to a few
guys in our local Airhead chapter. A few suppliers now offer brushless rotor systems with a combined
regulator/rectifier as well, good bye diode board. Plus you will gain significant power over stock.

The timing advance unit is also dated by modern standards. The centrifigual weights do need lubrication
every few decades, and that is not an easy task. (okay, I haven't tackled it, just parroting here).
New bean cans are available that are solid state, no more weights.

These two ideas will give you increased reliability and performance...
 
Modernization

I would suggest you consider upgrading the electrical charging and ignition systems...

The wire wound rotor and diode board were not even state of the art when the bikes were new, I would
suggest that a failed rotor is one of the most common faults with an airhead. Its happened to a few
guys in our local Airhead chapter. A few suppliers now offer brushless rotor systems with a combined
regulator/rectifier as well, good bye diode board. Plus you will gain significant power over stock.

The timing advance unit is also dated by modern standards. The centrifigual weights do need lubrication
every few decades, and that is not an easy task. (okay, I haven't tackled it, just parroting here).
New bean cans are available that are solid state, no more weights.

These two ideas will give you increased reliability and performance...

All good points. I would add updating the suspenion and brakes. Aftermarket shocks are just above the price point of BMW parts and are a great improvement. An easy improvement would be to go with an 81 or newer fork assembly which will give you better forks and Brembo brakes.
 
From the first time I saw a 1600cc VW engine in one, it never ceases to amaze me what can be stuffed into a /2 frame.
 
Not an Airhead but a slash 2 restomod.


Have seen that before, and I like it. I do wonder though how the frame handles the increased HP & torque ?
Would make a nice sidecar mule...if a person wanted to keep the vintage look, but have the increased power for highway, etc.
 
Have seen that before, and I like it. I do wonder though how the frame handles the increased HP & torque ?
Would make a nice sidecar mule...if a person wanted to keep the vintage look, but have the increased power for highway, etc.

Those frames were so over engineered. They are more than able to take that horsepower. People used to actually put Volkswagen (old bugs) engines in there with very little frame modifications as I understand it.
 
It would be cheaper and the end result better to simply obtain an '87-'95 R100. Or an R100R.

And FWIW at the '84 Missoula National there was a /2 (I think) with a BMW 2002 motor. It's been a decade or more since I've looked through my color slides. What?
 
It would be cheaper and the end result better to simply obtain an '87-'95 R100. Or an R100R.

And FWIW at the '84 Missoula National there was a /2 (I think) with a BMW 2002 motor. It's been a decade or more since I've looked through my color slides. What?

As a relative newbie still looking for the first airhead (at age 61 "newbie" ;) what are the relative advantages suspension/brake/electric wise of the years/models you suggest? And, still curious about the restomod idea. How expensive can it be to retrofit brakes, suspension and electric on, say, a $3,500 starter ride?
 
How expensive can it be to retrofit brakes, suspension and electric on, say, a $3,500 starter ride?

How long is a rope? You can spend a real chunk of change upgrading a /5 let's say, or you can put steel braided brake lines and
good pads, aftermarket springs and shocks and enjoy it as it is. I like my 86 R80RT for the dual discs and more modern(?) tire sizes.
It's down on power compared to a R100RS. My friend Woodensteel figures any Airhead is going to end up costing you about four grand...whether you start from a $1500 beater or a $3500 runner. Mac
 
As a relative newbie still looking for the first airhead (at age 61 "newbie" ;) what are the relative advantages suspension/brake/electric wise of the years/models you suggest? And, still curious about the restomod idea. How expensive can it be to retrofit brakes, suspension and electric on, say, a $3,500 starter ride?

I think you need to answer a question from yourself. What type of motorcycle do you like? For example, I like the look of the mid-80's airheads, and do not like the look of the later bikes (many of them), I also like the pre 1970's but the /2's were notoriously underpowered. Nice to look at (as picture above shows) but not up to riding on a regular basis.

It depends how much you want to "upgrade" in the way of new, non-stock items. Perhaps a complete engine like the above /2 has fitted?

It is all up to you!
 
I am a member of the ICOA, the Honda CBX Owner's association. Among CBX owners it is very poular to upgrade or "restomod" the CBX to bring it into the 20th century. The engine is a marvel and still fine with 100hp and doesn't need much mods, except for viton valve guide seals and maybe a different alternator.
Most modifications are addressing the terrible handling the original bike had, which will make it run at the end of the pack today, in spite of the wonderful 24-valve inline 6.

We are talking upside-down forks, different swingarms and shocks and better brakes and updated tire profiles. You can easily spend a couple of thousand dollars for these mods without totally altering the original appearance flair of the bike.
 
Not sure if anyone mentioned the suspenion changes...could put on a stout upper triple tree and maybe a fork brace. There was a brace that could be added to the swingarm that is very hard to see...not sure how much it did. If I can remember where I have it, there are a couple of articles that might provide some ideas for restomods.

- Black-Tie Boxer by Joe Minton, Motorcyclist August 1984
- King of the Boomers - http://www.omnilex.com/public/bmw78/kotb.pdf
- a final chapter in one of the Clymer manuals

Maybe someone can find these others on the web.
 
I'm just starting my own airhead journey so take this advice for what it's worth. I think a little frame bracing would be required for a restomod. I will be sliding a 4130 tube into the backbone, rosette welded, and a triangular plate to tie the rear down legs to the backbone. And something up front to anchor the back bone.
 
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