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R100s

S

SCDorman

Guest
Hello out there - I am thinking of purchasing a 77 R100S. 101k, REALLY nice shape, dual plugged, Konis, Lester mags, runs and stops extremely well (it nearly made me whoop out loud on the back roads). Non-original paint, but appropriate and in decent shape. Unfaired. Looks like it will take about $3500 to move it. My only airhead experience is with my 80 R65. Any thoughts on the vintage and model, things to watch out for, price?

Thanks, any input would be appreciated.

Steve
 
You know Steve, its only money. If you were looking to do a restoration, I'd advise against it. For a rider, it is difficult to get anything that's ready to run for much less than that. $3500 is the price you would be asked to pay for a P.O.S. Sportster.
 
if it feels good, do it

The 77 and 78 model airheads are regarded be many as the apex of airheadism. Especially the S and RS model bikes. Even without the fairing the S is still special because of the cam and other goodies. I own a 79 R100S and my model is the last year they were good, or the first year they were bad. If the bike is in good shape $3500 seems fair. I paid $3200 for mine a couple of years ago. Good Luck
 
Hello; I have a 77 R100/7, and amcompletely happy with it. It has been "S" ized and has had a port and polish and two plug heads. The only change I would consider would be to add a second brake disc to the front wheel. I have had it out for long trips (mre then 2000 miles) every year since I bought it, and it hasn't given me any trouble at all. I reccomend my bike to anyone and everyone who asks. The head work gave me quite a bit more power and made the bile sound better too. I should mention the Luftmeister two into one exhaust as well, I felt a little too anonymous with the stock exhaust, the Luftmeister cured that.
 
Re: if it feels good, do it

sbrick said:
The 77 and 78 model airheads are regarded be many as the apex of airheadism. Especially the S and RS model bikes. Even without the fairing the S is still special because of the cam and other goodies. I own a 79 R100S and my model is the last year they were good, or the first year they were bad. If the bike is in good shape $3500 seems fair. I paid $3200 for mine a couple of years ago. Good Luck

All '77-'78 USA Airheads had the same camshaft.

The later ones had the same cam specs, too, but the ignition drive connection was changed with the change to canister-style ignition.
 
Thanks for the input. I went ahead and purchased it. Had a blast on the way home. Certainly not as technologically advanced as my R11R, but somehow, more fun.

SD
 

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nice pic

Thanks for posting the picture. It looks sweet, especially those Lester wheels, they are special.
 
That definitely is a good looking 100S! ;)

Is it black or that dark metallic brown they offered then? The aluminum looks really clean too, can you link to some more pix?

My '78 is apart right now, but most of the time when I'm riding I ride w/o the fairing. The handling is noticeably lighter and I like the openness. Fairing gets reinstalled for long trips though, makes a big difference at the end of 500 mile-plus days!
 
Pretty! Looks like you got a good one! I don;t know if you know this but Koni got out of the motorcycle suspension biz but it appears that their tooling was sold to an Autralian outfit trading as Ikon. If you need to rebuild the shocks I think- but don't know for sure- that the Ikon parts should be a direct replacement.

If you really want to get in the know with this machine I recommend both airheads.org and boxerworks.com. Boxerworks is the one I use daily and there are some really knowledgeable folks there.
 
The paint is black, but a repaint job. Has blue piping. Not official BMW, but it looks pretty sweet. Thanks for the heads-up on Ikon, shocks are fine now, but it's good to know.

As luck would have it, the first day after I brought baby home, the ignition went kaput. I limped back to the dealership. I am anxiously awaiting her return, hopefully Monday. I should have expected it; it was the only thing not tested or replaced on the sale prep work order.

Anybody got any tips on fairings? I've seen them at Bob's and Parabellum.

I'll post or link some more pics once I have her back. Thanks to all for the interest/input.

Steve
 
>Anybody got any tips on fairings? I've seen them at Bob's and Parabellum.

They turn up on ebay from time to time. Bob's (or any dealer that's hip to "Mobile Traditions") will have new ones in stock. Quality always guaranteed with a new one, but you pay for it. I think the primed fairing will be around $600 once you get the bracket, dash, and instruments. Probably another $100-$200 for paint unless you can do it yourself. (You can buy a pretty nice spray gun for $100-$200 if you already have a suitable compressor) Just went that route myself when a painter friend wanted $150 to paint a helmet.
 
Well, the baby finally came home last night after spending 4 weeks waiting for a new ignition. However, it looks like she may be going back to the shop. Several times during the 100 mi I put on last night the engine stopped without any warning. Just a brief sag and then complete loss of power and stall. This is very disconcerting while passing a semi on the 4-lane. It starts right back up again (usually with a healthy backfire out of the exhaust), but ONLY if I turn the ignition off and then back on. Otherwise it just cranks. Is it possible that there is a sensor in the ignition (dealer said it was a Boyer) that is overheating or otherwise tripping, then resetting when I flip the key? Any thoughts would be appreciated. I am relatively new to bike mechanics and am trying to decide whether to tackle this myself.

Second question: at low speeds, the front wheel/brakes chirp quite a bit. This stops when the brakes are applied, or above 40 mph. The pads are new and stopping power is awesome, but the noise is irritating. The dealer told me they looked at it and everything is fine, sometime these older brakes do this. Does this make sense? Again, any input is appreciated.

These things aside, at speed (and running) this machine sure is sweet.
 
This is turning into some serious fun...in addition to those items mentioned, the turn signals, brake light and horn ceased operation today. Guess I'll have my head buried in the manual for awhile.
 
new challenges

While I am not highly experienced in later airhead electrics, I would point out that all the things your'e having trouble with are enabled by the main switch. Except those noisy brakes. Disc brake pads usually have spring steel clips to damp them from ringing in sympathy with the rotors. The brake noise is not much of an issue, really.
 
Thanks for the input. I am having fun with electrical diagrams (given no training). I'll advise how things go.
 
SCDorman said:
Second question: at low speeds, the front wheel/brakes chirp quite a bit. This stops when the brakes are applied, or above 40 mph. The pads are new and stopping power is awesome, but the noise is irritating. The dealer told me they looked at it and everything is fine, sometime these older brakes do this. Does this make sense? Again, any input is appreciated.

These things aside, at speed (and running) this machine sure is sweet.

Had that problem with my R100/7 and after replacing the pads (several times) it just seemed to get worse, then I looked at the disc itself, one thing I found was that the surface was not smooth, the area between the holes in the disc was scooped when I ran my finger across the disc from the inside out I could feel the ridges between the depressions on the surface, replaced the disc and the noise has vertually ceased, braking has improved as well.

As for any sensors, shouldn't be any, (cept maybe in the boyer?) one of the things I like about the older airheads is that fact there are no electronic components, many problems with electrics are just a short/lose/corroded connection (or bad relay or coil) somewhere, sometimes it can even be a case of a pinched wire, not broken completely just smashed enough to cause a point of high resistance. That just happened to my R100, headlight was getting dimmer, turns out one 2 nich section of ground wire from the light was getting hot to the touch, bypassed the piece that had been crushed (prob. some broken strands) and headlight is nice and bright again.

Good luck you got one of the strongest airhead motors made, as I understand it, after 78 they started "detuning" them with smaller valves and all.

RM
 
Brakes

Checked out the discs and there is some minor ridging, along with some rust. Could be the issue. Thanks for the idea. I'll try to clean them up before I spring for the new ones.

The manual suggests using laquer thinner as a cleaner...what's the appropriate medium for cleaning...steel wool?
 
Re: Brakes

SCDorman said:
The manual suggests using laquer thinner as a cleaner...what's the appropriate medium for cleaning...steel wool?

Either that or Scotchbrite?«. I usually use brake cleaner, because it (supposedly) doesn't leave any residue.
 
Re: Brakes

SCDorman said:
Checked out the discs and there is some minor ridging, along with some rust. Could be the issue. Thanks for the idea. I'll try to clean them up before I spring for the new ones.

The manual suggests using laquer thinner as a cleaner...what's the appropriate medium for cleaning...steel wool?

If you have to replace them you might look for used first though I'd want to be able to see them first hand and I found out that there are two types that will fit, the original is a "fixed" disc but some of the early year "floating" discs will bolt right up to the early wheels, they are supposed to be better, but not why, maybe someone else knows more about that issue.

RM
 
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