An R100RS Build: The shiny crumpet

Discussion in 'Airheads' started by xavier296, Oct 8, 2011.

  1. xavier296

    xavier296 Alaska n'Back

    Joined:
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    I have been getting loads of help in a questions thread about this bike, but I am finally getting on my butt and writing up a build thread. I am about a month into the build already, so I will start with the catch ups.

    I purchased this 79 R100RS cafe from London and had it shipped down to me in Naples, Italy. I am US military working in Naples, and thankfully worked very hard to ensure I had a garage in my place here. The bike has obviously been cobbled together with a mix of parts from various model years. The engine is the original R100 motor, but the front cover was from a later motor, the front suspension is from an 81-84 model (with Brembo brake calipers vice ate), and the controls are from the later model also. NONE of the original body panels remain. The front fender and rear cowl are caferace.com items, and the tank is a non-BMW aluminum tank from Terry Baker in the US. And by non-BMW, I mean that it wasn't meant to be fitted to a BMW. A rather ugly looking roll of foam was placed on the backbone and then the tank was set on top. Even one of the coils had to be relocated lower in order to accommodate the tank. In a word, the tank is a MESS. It rattles while riding all of the place, and touches metal to metal on many parts of the bike. The conversion was done sloppily at best!!

    I loved the polished tank from the pics before I bought it, but I am going to replace it with a stock tank. I like things that work.

    So, straight off the truck:
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    The fairing is not an S fairing, it is aftermarket, and held in with crappy looking brackets and zip ties. Boo. It came off:
    [​IMG]
    Gotta go eat, more later!!
    #1
  2. Padmei

    Padmei enamoured

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    I was thinking that I like it the way it is- then I noticed how shiny your other toys are & how organised your workshop is:D

    i can see this will be a very thorough build up:lol3
    Go for it & lots of pics please
    #2
  3. DoktorT

    DoktorT BigBrowedNeandereer

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    Well, welcome to the world of FrankenBeemers. Bet you could sell the tank for more than the cost of a stock tank, if you can determine what it will fit properly. I would consider hiring a craftsman to make up and weld in proper mounts as it is very trick looking.

    So much has to do with what you envision as ending up with. A stock 3/4 seat and tank with stock S fairing would not be cheap, but would be bolt on correct and maintain the cafe configuration. That will likely require painting unless you got really lucky so just be thinking about your favorite colors to go with your custom build.
    #3
  4. xavier296

    xavier296 Alaska n'Back

    Joined:
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    Thanks for the compliments!

    Before the bike even arrived, I started to put together some of the things I liked and what I wanted. to change immediately. I personally prefer the stock airbox look, and hated the battery location, so a fellow inmate sent me an awesome airbox and I ordered a few parts to get started. I had nothing else to work on, so I cleaned and polished the airbox:
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    I also prefer the stock black fuel line, not this ugly green stuff:
    [​IMG]

    Upon bike arrival, I removed the odyssey battery and fabbed up some mounts for it under the cowl. I came up with the idea of using the stock battery box modified and mounting it flat with the battery on it. That minimizes the welding and add-ons to the frame:
    [​IMG]

    The mounts are also above the plane of the frame, maximizing available suspension travel.
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    I also removed the horns from the stock location and installed them behind the battery, but I am not that happy with them, so that may evolve over time:
    [​IMG]
    #4
  5. vacantstare

    vacantstare Been here awhile

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    294
    I'd love to know how you got that air box SO clean...
    #5
  6. supershaft

    supershaft because I can

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    It seems a lot of people are turning their bread box into a battery box. There is no way I would run my lead weight out there. Twice as long battery cables too? Nein danka! If I ever make a cafe bike it for starters won't be a cafe bike. It will be a TT bike. I won't have a bread box behind my seat and I am not going to put one of my heaviest components so far from the center of mass. I am not going to take 20lb off the very end of my bike just to put 12 more right back in the same place! I am going to want my TT bike to handle so the mass will be as centralized as possible. It really does make a big diff!

    Sorry about the rant. A least it isn't a boat battery back there.

    Carry on.
    #6
  7. Houseoffubar

    Houseoffubar fine beer sampler

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    No kidding, that airbox looks great! Nice work!:clap
    #7
  8. xavier296

    xavier296 Alaska n'Back

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    Fubar: Your box was actually pretty clean on the inside, and the outside was cleaned with the following method:

    Scrub with red scotchbrite together with mothers aluminum polish till the surface is even, then polish with White Diamond metal polish. The mothers doesn't create much of a shine on the aluminum, but the White Diamond does an amazing job of bringing out the shine. It just takes a lot of coats and clean rags. Amazing stuff.

    The front cover on the engine was black, probably from the factory, and was chipped, so I went about making it pretty also:
    [​IMG]

    After two coats of aircraft stripper and a lot of time with a red scotchbrite. BTW, that aircraft stripper is bad stuff!! It ate through a set of yellow kitchen gloves and burns pretty nicely on the skin.
    [​IMG]

    Then some time with White Diamond. I think this was supposed to be a before and after. The left side is complete, the right is not.
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    I also went to work on the starter cover, which was definitely the worst item from the beginning. I didn't take a before pic:
    [​IMG]
    #8
  9. xavier296

    xavier296 Alaska n'Back

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    While the cover was off, I checked out out the electrics. Some ugliness and PO hack jobs:
    [​IMG]

    I thought I might find a bean can, but there are just normal points and some sort of fix on the camshaft end holding the advance mechanism. I have another set of points, and will change them soon, as these seem marginal, but they work. And the gap was set perfectly.

    Amazon sent a present which I paid for, and I have used it everywhere since:
    [​IMG]

    I love tools!!

    More parts showed up too:
    [​IMG]
    #9
  10. DoktorT

    DoktorT BigBrowedNeandereer

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    Both the badges on the starter cover, the front cover and those points say 78. Black front cover from the factory?? Not likely. Someone broke the threaded end off the cam and fixed it with a little bolt. Not the first time that's been done. If you got the bucks, you can get the aftermarket charging system with crank fire ignition. If not, good used stock parts will do the job. The brush holder has definately seen better days.

    Nice pix. You will certainly be a dyed in the wool Airhead when you get this one all spiffed up.

    Please be very serious about using chemicals. Read the precautions carefully. You can generate death fogs PDQ with the wrong move. Take it outside and have a charged hose ready for instant rinse and wash. Can you say, SAFETY GLASSES!!!!
    #10
  11. xavier296

    xavier296 Alaska n'Back

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    This bike has many later 81-84 parts on it, so I think the front cover came from that bike and was not original to the motor. But stock or not stock, the cover is not black anymore!

    Thanks for the advice, I bought a box of air masks and good safety glasses at the beginning of this project and have been wearing them a lot, especially around chemicals and the grinder. I wore them both for 8+ hrs while sanding on the exhaust pipes!
    #11
  12. xavier296

    xavier296 Alaska n'Back

    Joined:
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    the previous owner had installed an aluminum fender over the rear wheel and attached it to one of the battery box rubber hold downs. It was "rode hard and put away wet"!
    [​IMG]

    The rear battery placement called for its removal, but I wanted a fender to keep most of the junk off the motor, so I trimmed it and mounted it back up. I also sanded it smooth, 220 to 320 to 400 to 800 grit, then buffed it. You can see yourself in it. Hmm, no pics, I will add one soon:

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    Soo, let'a talk tail section:
    It came like this:
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    The rear light was a very cheap and rusty part with two dim bulbs. It also only worked when it felt like it. I ordered an installed an LED replacement. I realize it looks a little too modern, but it is very bright and flush mounted.
    Poor tail piece has been through a lot:
    [​IMG]

    I mounted the license plate holder up using the original holes then drilled holes for the new light:
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    Installed:
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    You might notice that I removed all but one sticker with a heat gun and finger nail, then used toilet bowl cleaner to restore the white color:
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    I also got some small LED license plate lights and installed them using posi-taps. I will replace all the electrical tape with shrink wrap when I take it all apart for paint.
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    #12
  13. xavier296

    xavier296 Alaska n'Back

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    Augusta, GA
    The bike came with no turn signals, but Italy will not allow me to register it without them. Thankfully, the PO had not removed any of the turn signal wiring, switches, or flasher, so it was as easy as finding the right wire colors and connecting them. I used cheap aluminum bodied units from dimecitycycles:

    [​IMG]
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    That same order had some new bar end mirrors from DC. I have only installed the right side so far. If you go to their website, they do not look exactly like the ones from the pics, but they look good and have a good field of view for their small size.

    [​IMG]
    #13
  14. DoktorT

    DoktorT BigBrowedNeandereer

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    On the lower right frame rail was a metalic sticker. It would have the month and date of manufacture and the VIN no. The engine will have the VIN no. on the boss for the oil fill. That always matched the frame no. it was originally installed in. The engine no. is on the oil pan perimeter left front side. The VIN is also stamped into the frame at the steering head gusset on the right. All that is for US delivery production.
    #14
  15. Dirtnadvil

    Dirtnadvil Been here awhile

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    This is a nice build to watch with my morning coffee back here in the states. Thanks for your service to our country :clap
    #15
  16. xavier296

    xavier296 Alaska n'Back

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    So, next project was exhaust: The bike came with stainless steel headers to hoske silencers.
    [​IMG]

    I like the look and sound of the hoske mufflers, but they were very rusty on the inside. Someone had occasionally cleaned the outward sections of the pipes, but they were toast on the inward parts.[​IMG]

    I attempted to clean the silencers, but all it did was scratch the chrome, so I gave in to new mufflers. New Hoskes are 450 dollars, so I bought some shorties from Dimecitycycles. They also carry longer versions, but I think the shorties look good. Before putting it all back together though, I spent about 6 hrs working the SS headers. It turns out that stainless still corrodes if heated, and these were BAD!! Note these pics were taken after a pretty good initial cleaning:
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    I started with 000 steel wool, then 00, then red scotchbrite, then I just gave in to sand paper. Some sections took as much as 60 grit paper, then I progressively moved up to 800 grit, then buffed with red compound.
    Before and after Comparo pic:
    [​IMG]

    I made some L brackets from the supplied brackets to mount the mufflers to the original mounting location. It came out looking very good:
    [​IMG]

    I have run the engine since installing, and the new mufflers have a heck of a bark. I haven't actually driven on the road yet, so I will report back on the final verdict.
    #16
  17. xavier296

    xavier296 Alaska n'Back

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    You might have noticed in the above picture, that one of the additions I made might not be very "cafe" like, but it sure is helpful:
    [​IMG]

    Right behind the shock mount on the left side is a powerlet connection. I used a 12" fused connector wired straight into the battery. This allows me to run a battery tender and maybe a heated vest in the colder months! When closed, it is practically invisible.
    #17
  18. xavier296

    xavier296 Alaska n'Back

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    Oddometer:
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    Augusta, GA
    I am starting to catch up. Last week was front suspension rebuild. The right fork was leaking from the fork seal and had managed to cover practically everything with a nice coating of oil and dirt. I also wanted to remove the black paint from the forks and install the new billet fork brace.
    Teardown:
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    Installation of the triple clamp means you have to cut .65 inches from the headlight ears, and it took me many many many hours of work with aircraft stripper, a scrapper, and metal polish to prepare the forks. I hate those forks lowers
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    I did a quick search, and just happened to have a 36 mm socket. I have no idea when I bought it, but I think it was for a rotary engine motor build I did a few years ago. I used the socket and some socket spacers inside to allow me to put pressure on the fork caps while installing them.
    [​IMG]

    In general I was impressed with the ease of installation of everything. No real lessons learned except that putting the new fork seals in the freezer made installation much easier.
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    The bike came a CC products fork brace, but it just didn't seem to fit correctly. The front of the fender stuck up very high . I think it is made for the earlier style forks. I purchased a used brace and fender from an 83 RS, and really like how much better it fits around the tire. I am going to cut down the fender, but haven't decided how much yet:
    Before look:
    [​IMG]

    After with correct brace. You can also see the lower forks now have the correct rubber lower fork tops. It used to have the older style fork tops on the new style forks. Much better:
    [​IMG]

    New reflectors are in the mail. Mine weren't perfect, but turns out that aircraft stripper eats plastic.
    #18
  19. xavier296

    xavier296 Alaska n'Back

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    I will do a full writeup of the rear suspension coming apart, but I have a question:

    How screwed am I???

    Rear wheel coming off:
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    I have no idea how long this has been collecting inside there. And it doesn't drip consistently. Actually, I have only seen one drip hanging off the whole time.
    #19
  20. danedg

    danedg Horizontally Opposed

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    Toilet bowl cleaner?


    :ear
    #20