A Swede and his BMW K100 build

[lalilulelo]

Hi guys, im from Sweden and this is my first build ever, i recently found this forum and have been reading a lot of threads here and finally decided to post the progress of my build here to. Normally i hang out at a Swedish forum but the community here is a lot more experienced and appreciative when it comes to these bikes so i figured i can share my story here to.

I think im going to have a hard time explaining what i've been up to when it comes to the bikes different parts since i dont know all the english words. I've also noticed that there are a lot K100 enthusiasts that dont like when we "destroy" the looks of the beautiful stock K100, im sorry if this thread is gonna get you upset.


I got the bike for 13000 SEK, should be around 1300 Euro and its a K100LT

Started off by stripping the bike

[Laitch]

Welcome, lalilulelo. Somebody will want all those discarded parts to restore an old brick so it all comes to a balance in the end. Good photographs!

[lalilulelo]

Working on fitting the saddle, welded on some metal plates and some "pipes" where the screws are going through, the saddle stays at its place perfectly. Also removed the "steering" (haha sounds so bad) and installed some clip ons. Also cut off a bit from the frame so the saddle looks better on

[lalilulelo]

Installed new grips on the clip ons and removed the tires so i could have the rims for repainted.

[lalilulelo]

So i bought a pair of nice LED turn signals for the rear of the bike that i wanted to fit in the frame, to my suprice they didnt work, after some searching i ended up here at motobrick where i found out that the relay box must be opened and the circuit board must be modified. I really dont know how you guys managed to bend it up with screwdrivers so me and my mate opened it up with a dremel and then put it back together with a glue pistol.

[lalilulelo]

So i decided i wanted the frame repainted and also the forks. Took everything of the bike so whats left is the motor and the swingarm. Also cutted of a lot of metal pieces that were on the frame which were useful when the bike was in its stock mode.

[lalilulelo]

I got the frame, forks, rims and front fender back from the painter, paid 430 euro for all of it, dont know if i made a good deal but it felt like it. I decided i wanted everything in matt black and im pretty happy with the result, i also made the front fender half the size by cutting it off in the front and the back, think it gives a more rough touch to the bike. I also bought some fork boots/gaiters and had them installed, i didnt have any clams/stripes at the moment but that will also come so the fork boots stay at their place. In the pictures you can see my new rear sets, i forgot to take focused pictures of them but they can be spotted, gave the bike a nice touch to.

This is how far i've come so far, i'll keep you guys updated, i think the next time will be in the beginning of march.

[lalilulelo]

Welcome, lalilulelo. Somebody will want all those discarded parts to restore an old brick so it all comes to a balance in the end. Good photographs!

Thank you! I have already sold most of the parts and god rid of the rest, i still have the saddle and the rear fender though.

[Laitch]

When did you start this project, lalilulelo, or did it only take you 51 minutes because you, your mates and the painter were drinking Swedish coffee by the liter?

[lalilulelo]

When did you start this project, lalilulelo, or did it only take you 51 minutes because you, your mates and the painter were drinking Swedish coffee by the liter?

Haha good one! I bought the bike in September and this is what i've managed to do so far, im borrowing my mates garage so i cant work as much as i want to do with it so instead of saying that this took 5 months to build i would like to say it have taken 30 hours so far, i've been documenting all the sessions.

[Elipten]

On that relay box. All you had to do is run a razor around the bottom edge to cut the silicone and then pry out the board as there are two tabs that hold it in place

[lalilulelo]

On that relay box. All you had to do is run a razor around the bottom edge to cut the silicone and then pry out the board as there are two tabs that hold it in place

I'll keep that in mind if i work on a K100 again :)

[lalilulelo]

By the way guys, i was wondering, me and my mate tried to remove the fuel cap but we didnt manage, and it felt like we had to use a lot of force so we decided to put it on hold since we didnt want to damage the fuel tank.

Any tips on how to do it easily?

[billday]

Just a general question.

Why are people making "cafe racers" out of K100s? The classic K is a terrible platform for the "cafe" genre: It's heavy (both literally and visually), the engine is loaded with peripheral systems that it needs to run (not least the radiator, which is the most un-"cafe" thing you can have on a "cafe racer"), the frame is not elegant or visually interesting . . .

No disrespect to lalilulelo or anyone else's efforts, but I am genuinely puzzled.

By the way guys, i was wondering, me and my mate tried to remove the fuel cap but we didnt manage, and it felt like we had to use a lot of force so we decided to put it on hold since we didnt want to damage the fuel tank.

Any tips on how to do it easily?

To answer your question, those screws bond with the aluminum tank. Make sure you're using a screwdriver that exactly fits the head of the screw, and give the screwdriver a few firm whacks with a hammer to break the corrosion. Press down hard on the screwdriver while backing out the screws.

[Laitch]

. . . we had to use a lot of force so we decided to put it on hold since we didnt want to damage the fuel tank.

Holding off was a good move. :clap:

I'd modify billday's approach just a little.
If it were my bike, I'd trickle some penetrant around each fastener, put a screwdriver on the head of each fastener and rap it a couple of times, put the screwdriver on the bench, wash my hands, pour a cup of coffee, use a heat gun to warm up a cider doughnut to eat, read a chapter from an Archer Mayor—or perhaps in your case, Henning Mankell—novel, play some handball or do something else productive for twenty minutes, return to the bike, put on my gloves, rap the fasteners a couple of more times then work the wrench back and forth, bit by bit until the fasteners loosened. Repeat if they don't come loose the first time.

Patience will work in this case, as it does in many other cases.

[Laitch]

Why are people making "cafe racers" out of K100s? The classic K is a terrible platform for the "cafe" genre: It's heavy (both literally and visually), the engine is loaded with peripheral systems that it needs to run (not least the radiator, which is the most un-"cafe" thing you can have on a "cafe racer"), the frame is not elegant or visually interesting . . .

No disrespect to lalilulelo or anyone else's efforts, but I am genuinely puzzled.

My guess is it's a satisfying artistic challenge that—unlike products from a potter's wheel—results in art that makes a lot of noise while raising the artist's pulse rate, and reinforces the age-old proposition that just because she's not cute to you doesn't mean she's not hot to me. :hehehe  Anyway, it's way better than neglecting the bike, or trying to remodel people instead.

[lalilulelo]

No harm done, the K100 has a good reputation of being a nice cafe bike, i can agree with u when it comes to the radiator but in overall thats not a issue when u have the solid K engine that just keeps on going no matter how old it is which can be a problem when it comes to other manufacturers.

Besides the BMW's excellent reliability the big front Fichtel and Sachs Forks are very good (rarely see K builders replace the front forks while other brands very often get the front fork changed), it has a MONO suspension in the back which is beautiful in cafe ways, the bosch electronics and brembo brakes.

Just google BMW K100 cafe racer or scrambler and you will se some nice bikes, then again beauty is in the eyes of the beholder.

[The Mighty Gryphon]

While I may poke some fun at the builders of cafe bricks, I must admit that some of them are quite attractive and have a certain look not found in cafe versions of other machines. 

The one thing that always catches my eye with these conversions is the unfortunate upward swept angle at the bottom rear of the fuel tank.  Hardly any of the builders address how this angle clashes with the horizontal lines of the seat and cafe tail cowl.  In all the photos I have seen of these bikes I can only think of one or two where this has been addressed by simply raising the front of the tank a few centimeters.   The effect on the overall appearance is dramatic.  I wonder why more builders don't do it when they expend so much effort in other areas.

[Laitch]

I wonder why more builders don't do it when they expend so much effort in other areas.

I think it's because they embrace Cubism. My bike sure strikes me as an example of it.

[lalilulelo]

Im thinking about buying an anti gravity battery, the 8 cell type, does anyone have experience when it comes to these batteries and the K-bikes? Read somewhere else that maybe the voltage regulator needs to be changed so the battery doesn't get destroyed.

Anyone with some experience on this?

http://shop.antigravitybatteries.com/antigravity-batteries-ag801/

[Martin]

I wouldn't buy one, if let it go it would float away :hehehe
Regards Martin

[rbm]

The one thing that always catches my eye with these conversions is the unfortunate upward swept angle at the bottom rear of the fuel tank.  Hardly any of the builders address how this angle clashes with the horizontal lines of the seat and cafe tail cowl. 

Exactly Gryph. Only one builder has ever addressed the tank and that's the Kaugusta (at www.Specialks.net).  Larry took an Italian inspired tank and placed it on the K100 frame.  More builders need to ditch that monster and replace it with curvey beautifully formed tanks that accentuate the motor and body.

[The Mighty Gryphon]

Rob, I recently saw photos of, I think, a German build where the front of the tank had been raised a couple centimeters.  The lines of the bike were so much better.  Lost some fuel capacity, but with cafe seats who goes more than a few miles at a time anyway.  Wish I could remember where I saw them.

[lalilulelo]

Asking again about the battery with some more info.

I Emailed antigravity regarding if their batteries work on the K100 and this is the answer they gave me.

"for your BMW we would definitely size you up for a 12-cell battery for that size of an engine as long as your Voltage regulator is reading at the appropriate volts which is no higher than 14.5 volts and using a Lithium or Liefpov4 charger."


Google around a bit for the Voltage Regulator on stock BMW and they seem to be handling between 14.1-14.5 Volts, anyone who can verify this?

Then i dont know if it is using a Lithium or Liefpov4 charger, whatever that is, anyone who can enlighten me on this?

[The Mighty Gryphon]

I am assuming that Antigravity is a trade name for a lithium battery that can be mounted in any orientation.

It sounds like the battery is designed to be used with an automotive alternator.  For an external charger it sounds like they want you to use something that is designed for charging lithium batteries.

Can't speak to the no load output voltage of the Bosch alternator, but it should be pretty easy for you to find.