BMW_logo.jpg PROJECT S    BMW_logo.jpg

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                                                                                                                                                                                                From this…                                                                                                                                                                                                to THIS!

R100RT_0004B_750pix.jpg       Sunday_49d_resize.jpg

                                                                                                                                                                          1979 BMW R100 RT                                                                                                                                                                                                           1979 BMW R100 S


The Back Story

In 1978 I got married and bought a home in Torrance CA. The Local BMW shop was Marty’s BMW on Carson Street and Western Avenue.

Marty's BMW store_front.gif

I would go into Marty’s and ogle the BMWs knowing I couldn’t afford one, but motorcycle lust prevailed. I would pick up a brochure on the latest vunder bikes and dream…

R100 RT Brochure 2-2.jpg



That’s me doing my best George “The Parts Guy” thumbs up!

April 2011, happy 57th birthday to me.


Meet Chuck. Chuck sold me his beloved RT.

Don’t worry Chuck, I’ll take good care of her for you.


The ride home.

The weather was very “Bavarian” that day, overcast and chance of rain.


R90S fairing from Bob’s BMW,

I ordered the "S" fairing, shield and hardware kit from Bob's BMW back east. I know Bob Hanna from his work with the Pediatric Brain Tumor Foundation. Bob is a big Ride for Kids supporter, and all around good guy, so I wanted to support his business.

I couldn’t believe it when I found out that the OEM “S” fairing was still available from BMW. I figure there are twice as many “S” converted bikes on the road as there were original R90S built, and why not, the R90S is an iconic motorcycle, the 911 of motorcycles. What motorcycle enthusiast wouldn’t want an “S” in their collection.


R90S fairing installation kit from Bob’s BMW,

Yes, the price was more than I wanted to spend ($757), BUT, if I had gone with the Airtech "replica" fairing I would have never been truly happy with the project. Ya, I could have found a lower price option, but then again, you end up paying in your time trying to duplicate the OEM installation. The OEM fairing itself was $387 all over town, the Airtech is $225. The OEM wind screen was $129, and aftermarket is $90. It's the hardware kit that really broke the bank at $199, but, I save huge amounts of time searching and fabricating hardware and in the end get an OEM installation as opposed to fabricating some sort of Frankenstein installation myself, no thanks.


As this project progresses I'm sure I will get nickel and dimmed every time I turn around, but it's cheaper than therapy!



Ebay find, headlamp ears.

For phase one of this project I will be pulling the entire RT fairing off and remount the headlight onto the forks. The RT has a sub-frame that supports the fairing and the headlamp, so, to complete the conversation to a “naked bike” I needed to find a pair of ears. All I need now are the rubber donuts that support the ears on the forks.

Ebay is my friend. I’m finding there are plenty of airhead parts on Ebay and many are reasonably priced. Then again, there are a few sellers that are out of the minds with their pricing… but ha, that’s Ebay for ya.


Already have the 27mm swing arm socket in my tool box from my old R65/5 Toaster Tank days.

Going to pull the trans as soon as I can to inspect the clutch. On the ride home the clutch seemed to be an ON/OFF switch with little actual transition action. The good news, no clutch slippage on hard acceleration was detected during the ride home (“hard acceleration”!? Ya, right, this is a gentlemanly motorcycle, it simple gathers momentum).


Cycle Works,

I need to pull the exhaust to get the RT fairing off... ya I know, ya don't need to pull the exhaust yada yada yada, BUT, this bike had the lower fairing repaired at one time and they glassed in the lower fairing split.

And yes, I do stamp all my tools with my nick name, “TINK”.


C20: Chrome Flanders BMW R90S Bar (Magura style 478-46300),

Picking up a pair of R90S bars from Paul Flanders. Paul’s another great Ride for Kids supporter. He helps make the So Cal Dual Sport Ride for Kids ride happen every year. Pauls’s also very active in AMA District 37 Dual Sport,

When I was a kid building bikes in Seattle, Flanders handlebars were the industry standard for quality motorcycle handlebars, and they still are today. The fact that they make 22mm diameter bars exclusively for BMWs shows they know their stuff and care enough to make their bars the right way.

Got the bars last night and compared them to the bars on my 2004 Suzuki Bandit 1200/S. They are almost an exact match, except the Suzuki bars are 7/8” and the BMW bars are 22mm in diameter. Interesting, don’t you think, that Suzuki would copy BMW R90S bars.


Another Ebay find! A pair of turn signals for $32 shipped to my door. New, turn signals are still just $25 each, after shipping, a new pair cost about $60. So, in the end I get a good-as-new set of used units for half price. I’m happy.



Am I the only one that finds it amazing that I can walk into my local BMW dealer and give them a list of rubber parts for a 32 year old motorcycle and the parts guy says “Yep, we got everything in stock”. Only BMW would be so loyal to its brand that they would continue to support a THIRTY TWO YEAR OLD motorcycle design. Now that’s nothing short of amazing.


And that's what I find amazing about BMW in this age of full model redesign every two to three years. There's no way any manufacturer can to keep up its parts inventory with this constant obsession with continual redesigning models for the sake of just being the newest next big thing. It's refreshing to know that BMW continues to respect its heritage and retains some sense of self when so many of the other motorcycle companies are caught up in a continual battle with itself against being left behind on "The Next Big Thing".




This R100S showed up at the May 2011 Vintage Bike OC meet. Mechanically she’s in top condition. Color choice… hmmmmm. Guy said he was going to repaint it, but the blue paint is in great condition so he decided to just ride the bike and enjoy it as is.


Had a chance to look at the S fairing install details up close and take lots of pictures for later.

01_IKON_750pix.JPG                   02_IKON_750pix.JPG                  

I knew I would have to upgrade the suspension, both front and rear, as the original BMW OEM shocks were in bad shape. At thirty two years of age, normal wear and tear had left them with zero dampening affect. On the ride home I knew they were junk as I cruised along enjoying the “Buick like” ride of the deceased rear shocks.

My initial research led me to “the usual suspects”; Works, Race Tech, Progressive. All fine shocks that I had used on bike builds of the past. But really, this is classic BMW Airhead, and modern shocks, as good as they are, do not provide that classic BMW look. Back in the day, KONI was “the” aftermarket replacement shock of choice for the discriminating BMW owner who wanted to ride his BMW at a rapid pace.

I happened upon a pair of original KONI 7610-1298 new old stock in the original box on eBay. Bidding started at $100, went to $125, and then sat there for the next 4 days. I logged on 2 minutes before the auction closed to find the bidding had pushed the price up to $275, ouch. I still though it would be cool to have actual “KONI” shocks, so I bid $285, do’h. Then 20 seconds before the auction closed a bid for $290… I fire back with $295, but, was second in line at $295 and did not win, rats!




That’s okay, I went ahead and ordered a brand new set of IKON (KONI with the “I” moved to the front) 7610-1298 (same part number at KONI used) for $414 from IKON USA, Dave Garner.


I’m really better off with a freshly manufactured set of IKON than a 15 year old set of KONI’s, that would likely need to be broken down and serviced before I installed them on the bike.


IKON shocks are the old KONI shocks, right down to the same part number. IKON bought the entire KONI motorcycle business and makes KONI tooled IKON shocks in Australia now. They are so true to the original, you can buy IKON guts and use them to rebuild your old KONI’s, what I would have likely had to do to the eBay KONI’s, had I won the bid.








Here they are! They’re beautiful! Can’t wait to put them on and go for a ride… hmmmm, that will be some time from now. My intention is to go through and bike and check everything mechanical before I put her back on the road again. What they call in the airline service business a “Heavy Check”. So for now, the IKON’s stay in the box on the shelf next to my brand new BMW OEM R90S fairing.



Started pulling the fairing off today. Got the windshield and the pockets removed. Next I need to pull the front forks to remove the remainder of the upper fairing.




The fairing is in “serviceable” condition. It definitly needs to be repainted though. The clear coat is delaminating in several locations. But for the most part the integrity of the fairing is solid (with one exception… see below)





The clear coat along with the pin strips is completely gone on the right upper fairing. It has some scrapes on the edge, not bad though, just the paint has been scuffed away.




With the left mirror swung down, you can see the left side upper windshield mount has broken and an attempt at a repair remains. Not a big deal really, have all the pieces, just need to do a proper repair, with some glass cloth reinforcement this time.



Here’s the right side, you can see what it’s suppose to look like.



With the headlight protector removed (a heavy piece of tempered glass) and the boot pulled inside out, I can access the inside the fairing. There’s a small running light that goes in the slot above. Plate in the center holds the windshield to the fairing; two 8mm nuts on the back side are accessed through the running light slot.




Here’s what I removed today, day one.


I’ll be boxing it all up and will decide later if I want to keep the RT fairing or just sell it off. Yes, there are a spare set of pocket covers there, and yes I do have the key for the pocket cover locks.




Windshield, like the fairing, is in “serviceable” condition. No major blemishes, just the normal wear and tear one would expect from a 32 year old bike that had been ridden.




Defairing, day two. The remainder of the RT fairing bits are off.



Now THAT’s more like it.


Like fine wine, an airhead should be allowed to breath…


I decided to start her up and take her for a ride down the street before draining out the old gas. Choke on, hit the starter, and she fires to life. After a minute or so I release the choke and she idles nicely with that BMW thump-a thump-a. Helmet on, I throw a leg over her and tap the gear shift into first, release the clutch and she moves down the street smartly. The clutch engauges at the very end of the lever throw, this may be normal, but I have no way to know. She purrs along smoothly and springs to life when I give her the gas. I’m convinced this bike is mechanically sound. It has almost no miles, 38K, on her and displays no signs of mechanical wear. No blue oil smoke. Carbs seem to be functioning properly. No bad noise coming from the trans or clutch. Valves make a small amount of clatter, but this may just be the normal BMW way… I have not yet to check the valve lash. All in all I’m very pleased with this bike and can’t wait to get her checked out competely and on the road again. I still want to walk through each aspect of the bikes mechanics; brakes, suspension, motor before I get her insured and on the road for some fun. I’ve decided that for phase one I will not worry about the cosmetic things like paint and chrome, but rather give each part a good cleaning and leave the original patina as is for now.



The tank has a small dent on the left side just below the BMW emblem and the paint has been scuffed through to the metal by the fairing pocket. Other than that the tank is in remakably good condition. The inside of the tank still has the original BMW protective coating and zero signs of rust. This is definitly a California bike given the overall condition of the metal parts.



Splendid simplicity!



The last of the RT fairing hardware is off. Now I have to decide if I’m going to keep the RT fairing in storeage, or sell it off. Time will tell.




Did a rough install of the headlamp ears. Going to take the forks off next to do a rebuild and install new IKON springs, so no reason the finish off the headlamp mounts until after the forks have been rebuilt.



Put to R90S bars on, very Café Racer. Much lower then the RT bars, and a few inches narrower too.




She’s starting to come together now!






Bought a pair of IKON 500-084 fork springs to complement the IKON 7610-1298 rear shocks I already bought.  I have no idea what I have for fork springs currently. They could be the originals, that are now 32 years old, ugh! They may be aftermarket, but no way to tell. In either case  it’s better to start with a known set of matching springs than to guess if the springs that came with the bike are serviceable, or not.


The RT fairing is quite heavy and I would expect the weight of the fairing put a bit of extra stress on the fork springs. Considering the added weight of the fairing and the age of the bike (and springs, I suspect) I’d rather spend a few bucks to make the front suspension right.



Another special tool for the BMW. This socket is for the forks. Both the top and bottom fork nuts and the triple tree steering stem nut are 36mm.





I modified the socket (top) by grinding down the lip to remove the beveled portion of the socket (bottom). I did this to allow maximum grip between the socket teeth and the nut head. The top fork nuts are not very tall, and with the bevel the socket would likely slip off the nut as I apply torque, thus rounding the corners of the nut… ask me how I know, do’h!

13mm.jpg 13mm2.jpg    


This tool was a suggestion in the CLYMER manual. By grinding down the sides of a 13mm socket to accomidate a 15mm open end wrench one can loosen the damper rod locking nut while holding the damper rod with a allen wrench.





Found this very cool picture of what appears to be the R90S press intro. Notice the black bike in the foreground; it has neither silver smoke paint nor pin striping. My guess is this bike was a prototype bike, or perhaps a color option BMW wanted to get press reaction to? Regardless, this is how I plan to paint my project bike, straight gloss black. I like it!


CORRECTION: Thanks to Max Headroom of New Zealand the source of the mystery photo has been revealed:

“Interesting guess, but no cigar . . . .
That's a photo taken in Holland showing a gathering organized by a gentleman by the name of Theo
Terwel [] who owns a business which specializes in painting R90S bodywork. That particular gathering was held only a few years ago IIRC.”


Click on the photo to view slide show.


I was having a very lazy Sunday and didn’t want to get into working on the BMW but I wanted to spend some time studying her. So I took my camera, set it to Black & White, and just started taking some “art” shots just to see what I could come up with.




I took off the saddle bag mounts, and replaced the tail light with an earlier (smaller) unit today. The tail light that came with the bike was an unsightly large unit with separate brake and tail light bulbs. It had suffered from the common error of putting too big a bulb in the tail light socket which over heats and damages the tail light lens. Got this good condition early tail light unit off E-bay for $38, including shipping.


Had to do a little work on the turn signals too. The right turn signal mounting stem was bent backwards sightly. Easy enough to bend back into place with a small cheater bar. The left turn signal housing internal mounting hardware had suffered some slight damage (from a tip-over I suspect) but was easily bent back into shape.










ATTENTION: I’ve stopped updating this blog page and have migrated to a thread on >





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Last updated: 2013-05-01