How would you Modernize an R100RS?

[DOINTHETON]

Pezz_gs,
do it man! i love modded airhead hot rods, especially ones out of the norm. i've owned numerous /6 and /7's and done all the afore-mentioned obligitory suspension mods. front fork brace, billet upper triple clamp, heavier front fork springs, aftermarket rear shocks, etc. seat of the pants, nope, never could tell any difference and my ass has been planted in three different r100's, three r90/6's, an r80 r/t converted to cafe spec, one r80st, two /5's, and three r100gs's so i think my airhead experience is well rounded.
onward and upward Pez!

 

[88bmwjeff]

keelerb, your question is best answered, "because I can ... I want to ... so why not !"

I agree with your comment. For the most part, people are limited by their knowledge, experience and available funds to make such modifications. So, for many people it is better and cheaper to buy what they want versus creating it from scratch.

I think when talking about modifications, one should consider their ability as well. For me thinking about what Pezz_gs is contemplating is not worth the time and effort. BUT, that's because I do not have the knowledge, expertise, or equipment to do that, and paying someone would not be cost effective (or within my budget). On the flip side, I enjoy seeing what other people with those skills are able to do.

 

[orbitangel]

Dead Animal?

Thanks for the great replies.

The 70HP RS engine is now in my R80G/S Dakar

A little about the R80G/S Dakar... It is the sweetest ride.

I prefer the old Airheads and I have a few. Looking at the Chassis evolution of the GuzziÔÇÖs one wonders where Airheads would be today?

Yes, PGS, but what the hell is that dead animal on your Dakar machine?

I mention this only because I am constantly harassed about the dead animal on MY bike.

I am fascinated by your idea. The clunky, old Gummikow is both loved, hated, revered, praised and derided by many. I happen to love it. What do I like about the RS?

It is STABLE, PREDICTABLE and RELIABLE. Also, it is very easy to maintain. It offers great value for the price.

Is the RS "perfect?" CERTAINLY NOT! It can be improved in LOTS of ways, large and small. For those who aren't fixated on having everything 100% original there are many opportunities to do something.

Personally, I'd like to shave a bunch of weight off. One way would be to do a much lighter version of the RS fairing.

The stocker is a beautiful piece of work but is very heavy. I'd like to have on made of carbon fiber, put together with quick-release fasteners like Camlocs. How about installing much better lighting? or a better (and lighter) seat?

Don't get me wrong: I'm all in favor of more power, improved chassis, better brakes and all the rest.

The biggest problem I see is basically a mission statement - what are the true goals, how far does one take this, how much are you willing to spend, etc.?

You have some VERY nice machines! I wish you all the best and will be anxious to see what you come up with.

Charlie

 

[keelerb]

You know, after making that comment, I wandered out to the garage, where my glance fell, as it is wont to do, on my 73 Commando with its electronic ignition, three-phase alternator, H4 headlight on a relayed connection, drilled/blanchard ground rotor, Keihin FCR carburetors, custom ignition switch, 520 x-ring chain, Ikon shocks, Progressive fork springs, Corbin seat, etc. etc. etc. and I said to myself, "Self, WTF are you talking about?"

I stand corrected!

 

[Pezz_gs]

Vanzen: I could not have put it better myself

I am printing that reply and posting it above my monitor

Orbitangel: Its a necessary investment, Merino Sheep Skin and I have had it for a number of years. Lots of Long days in the saddle traveling over here.

 

[VANZEN]

mission

... a mission statement - what are the true goals, how far does one take this, how much are you willing to spend, etc.?...
Charlie

A mission statement will be THE place to start.
A fact often missed, if one is thorough and honest,
is that the cost of resurrecting a Type-247 to "as new" condition mechanically and cosmetically,
plus the cost of introducing up-dates, modifications, and improvements ...
will very often be greater than the cost of a NEW bike.

This objective analysis will separate the "gear-head" from the "consumer".
Not intended to be judgmental, just two distinct groups of enthusiasts,
and I would qualify for both ÔÇô
given that I own and ride an R1200S
in addition to my quest of building a very special Type-247.


keelerb:
LOL. No correction necessary. You see ! No one is entirely exempt !
Just as soon as one decides that a sheepskin might make that air-head just a little more comfortable ...
or those Moto-Lights ... just a little safer ...
he gingerly begins the slide down that long and slippery slope called: "no longer 100% stock" !!!

 

[bob_m]

... the cost of resurrecting a Type-247 to "as new" condition mechanically and cosmetically, plus the cost of introducing up-dates, modifications, and improvements ... will very often be greater than the cost of a NEW bike.

Ain't that the truth. Still, you can have a machine that is just as reliable as a K12LT, and way cooler, for the same money.

DAMHIK

 

[VANZEN]

CF vs Epoxy FRP

...
Personally, I'd like to shave a bunch of weight off. One way would be to do a much lighter version of the RS fairing.

The stocker is a beautiful piece of work but is very heavy. I'd like to have on made of carbon fiber, put together with quick-release fasteners like Camlocs. How about installing much better lighting? or a better (and lighter) seat?

Carbon fiber has a definite "cool factor" and is truly beautiful, light, & strong stuff !
My last build used an S-type fairing, frame mounted, and fenders of CF –
tank & seat-base of aluminum ... as a successful attempt at weight loss.
But considering the process (vacuum bagging necessary w/ CF to achieve the light weight) and the cost ...
and you might consider that an Epoxy FRP will be a viable alternative.
Resulting weight of a quality epoxy lay-up can approach that of CF,
and will be considerably lighter than the stock pieces (polyester based SMC, or Sheet Molded Compound)
Strength required for the parts in question (fairing & seat) is more than adequate with epoxy FRP,
and the cost will be much, much cheaper.
Much easier to repair, too !

 

[orbitangel]

Yea, Verily

A mission statement will be THE place to start.
A fact often missed, if one is thorough and honest,
is that the cost of resurrecting a Type-247 to "as new" condition mechanically and cosmetically,
plus the cost of introducing up-dates, modifications, and improvements ...
will very often be greater than the cost of a NEW bike.

This objective analysis will separate the "gear-head" from the "consumer".
Not intended to be judgmental, just two distinct groups of enthusiasts,
and I would qualify for both ÔÇô
given that I own and ride an R1200S
in addition to my quest of building a very special Type-247.


keelerb:
LOL. No correction necessary. You see ! No one is entirely exempt !
Just as soon as one decides that a sheepskin might make that air-head just a little more comfortable ...
or those Moto-Lights ... just a little safer ...
he gingerly begins the slide down that long and slippery slope called: "no longer 100% stock" !!!

Astutely stated, as always!

 

[kstoo]

This is a good and interesting thread but I was initially disappointed because I thought that some CEO at BMW Motorrad should be asking the engineering dept. "How would you build a modern R100RS?"

I want an air-cooled, shaft driven 2-valve OHC fuel-injected opposed twin between 70 - 80 hp in a light sturdy frame with an ABS option that has the light-weight retro Hans Muth RS fairing that is easy to remove for maintenance. Must be able to mount Krauser type luggage to it as well.

Please?

and under $10,000.

 

[seniorasi]

"modern" vs custom fitted?

While the advances in technology may equate to "modern" in the minds of some, including the "perceived majority", what do you think about taking a different tack? How about building the dream bike with all the features you ever wanted in a machine?

 

[kstoo]

How about building the dream bike with all the features you ever wanted in a machine?

This is a good and interesting thread but I was initially disappointed because I thought that some CEO at BMW Motorrad should be asking the engineering dept. "How would you build a modern R100RS?"

I want an air-cooled, shaft driven 2-valve OHC fuel-injected opposed twin between 70 - 80 hp in a light sturdy frame with an ABS option that has the light-weight retro Hans Muth RS fairing that is easy to remove for maintenance. Must be able to mount Krauser type luggage to it as well.

Please?

and under $10,000.

 

[VANZEN]

they did

...This is a good and interesting thread but I was initially disappointed because I thought that some CEO at BMW Motorrad should be asking the engineering dept. "How would you build a modern R100RS?"
...

They did, and we now call it the "Oilhead".

The first attempt that I know of to build a "modern R100RS" was in 1989-1992,
The research / engineering team of Georg Emmersberger (Desmodromics), Heinz Hege and Ralf Lewien
came up with this sport race-oriented prototype known as the BMW R-1:

Tech specs:
Performance: 135 -140 Hp (100 - 103 KW). max rpm 11.000
Engine: 4-stroke two-cil. boxerengine, liquid cooled.
Four valves per cyl. ; DOHC DESMODROMIC VG
Bore-stroke: 98 x 66 mm. 996 ccm.
Bosch Fuelinjection; electronic ignition, 6 gear, cardan.
Dry weight 165 kg.

the BMW R-1 engine:

Only 4 prototypes were made – one of them ridable.

 

[VANZEN]

Dreams & a Design Plan

While the advances in technology may equate to "modern" in the minds of some, including the "perceived majority", what do you think about taking a different tack? How about building the dream bike with all the features you ever wanted in a machine?

My design plan or "tack" was to begin with a 1980 production model
and retrofit the machine with the leading edge technology of the era.
Technology which never made it's way into production until later
and would only have been evidenced on prototype and race bikes of that time.
The strategy is somewhat different in focus and intent
than that of attempting to recreate a "modern" machine from one that is almost 30 years old.
To my mind, an oilhead or hex-head might better (and less expensively) achieve that goal.

My concept puts me in that same place as the likes of Udo Gietl and Rob North
(although having the advantage of hindsight),
to pursue the task of building a "state of the art / 1980s vintage" machine,
and is certainly a feasible goal ... or so I would think.

The greatest advances in motorcycle engineering / technology have been in chassis design,
and this, the result of a need to cope with increased power output and rapidly changing tire technology.
Add in excellent braking capability, and the scene is set.
Advance one or another of these technologies on an old bike and you may be taking a step backwards.
I again stress the importance of thinking in terms of a "well integrated system" when considering changes ...

Given the nominally low power output of the stock Type-247 ...
it's limited capacity to accommodate modern tires ...
and ineffectual braking ...
one might well ask the question "why?" as keelerb did.
Start from the beginning, however, and it's a whole new ball game.

My "beginning" was to design a frame
that could effectively handle @ 90HP,
41 mm forks fitted with 2 - 305 mm rotors / 2-pot calipers,
race compound rubber front and back:

 

[PHMARVIN]

Hi, John,
So YOU bought the bike from Lyle Butler's estate in El Paso! Did you get the extra fairing, too? I was interested, but at that time it was out of my price range. Years earlier Lyle and I were both in the (defunct) BMW club in El Paso, the Sunbeemers. He sold me the original exhaust system after San Jose put the 40mm exhaust on the bike.

I have a '78 R100RS "Motorsport" edition (aka "The White Lion") with >$11K of performance upgrades installed by San Jose BMW, including:

* $650 OHLINS rear shocks + rear swing-arm bracing
* Triple-thickness, CC Products billet aluminum triple clamp
* San Jose front fork brace
* Dual-head plugs, DYNA-III electronic ignition
* 1050cc "Blitz-Kit" / new pistons / valves, etc.
* Stainless steel brake lines, new Metzlers / Custom CORBIN seat
* Etc., etc. - - - Read more here at www.vintagemotorcyclesonline.com

At the end of the day, it is STILL a 31-year old bike and should be ridden accordingly.

NOTE: I bought the bike already completed like I described above.....

Enjoy your R100RS for what it is...and add a modern bike to the stable!

JJ Cerilli
(Pleasanton, CA)

 

[kstoo]

They did, and we now call it the "Oilhead".

... which is (as a whole) everything that I don't want in a bike. Simplify. Can I work on it? Can I afford it?

The first attempt that I know of to build a "modern R100RS" ... sport race-oriented prototype known as the BMW R-1

... intimidating ... interesting but intimidating.

Finally, yeah, if BMW Motorrad were to build a "modern classic" (see MG V7, Triumph Bonneville) they should really start with your frame. Spot on. Perfect.

Only don't use the dog in the brochure because he really makes the motorcycle look small ... really small.

 

[mmmalmberg]

What always killed the RS for me was the amount of wind noise. I loved everything about my '92 RS, except that even with earplugs it was painfully loud. I think it's quite a shame that such a beautiful fairing, which defines the RS, and works so well in every other way, should be so loud as to cause some people to choose other bikes...

So for me, I would need to redesign the fairing to keep the essence of the look but clean up or redirect airflow at the top of the windscreen. Most attempts to do this with aftermarket windscreens just don't look that great and from what I've read, have varied or questionable degrees of success...

 

[20774]

What always killed the RS for me was the amount of wind noise. I loved everything about my '92 RS, except that even with earplugs it was painfully loud.

I've wondered about this with my /2...I realize it's not the same bike, but there maybe similar issues here. I have a small handlebar fairing on the R69S, so the top part of my torso is at or near the top of the screen. Which means my head is more or less in the wind...probably like the RS. I've worn a full face helmet behind my /2 fairing and noticed a certain amount of noise. If I stand up on the pegs, the noise quietens noticeably. If I duck down behind the glass, it's even quieter as expected. So it's clear that where my head is when sitting normally is where the dirty air is coming off the glass. Possibly that's the situation with the RS and your sitting position. A little movement one direction or the other and the noise could be quite a bit less. Just a thought...

 

[mmmalmberg]

Certainly true but for anything close to a "normal" riding position on the RS it's just too loud for me. I had a /2 for many years and I consider it to have been the most versatile of my bikes - I even took it up and down singletrack trails to a swimhole only accessible by foot or dirtbike It just had such perfect torque down to about 10 rpm. On that bike I had a 50's police-style windscreen, thin plastic with the 1/4" clear plastic bead around the edge and a chrome cross piece in the middle. That windscreen worked great and riding that bike across the US was like a dream, I felt like a bird with almost no sound at all. Loved that bike...

Completely off topic to be sure - apologies to the original poster

 

[skiteach]

Only don't use the dog in the brochure because he really makes the motorcycle look small ... really small.

Maybe it's a really big Stafordshire Terrier!