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How to build a BMW K100 Cafe Racer

BMW K100 cafe Racer depósito original

We are going to build a BMW K100 Cafe Racer step by step, it is also valid for a BMW K75, since aesthetically they are very similar. Here we go.

The BMW K100 and the BMW K75 are, in their own right, two of the bikes most transformed into Cafe Racer. They are probably the easiest classic BMWs to come by, and also the most affordable. They’re not too old, so you don’t have to worry about major mechanical problems, and their engines are literally indestructible.

BMW K100 vs BMW K75

These reasons, in addition to the immense potential they have, make both models two clear candidates for making a Cafe Racer.

We are going to make a BMW K100 Cafe Racer step by step , piece by piece, giving you ideas to transform it.

What can we change in a BMW K100 Cafe Racer?

Front light

Changing or not changing the headlight of a BMW K100 or a BMW K75 depends on the model you have. If your model is a square headlight, I’m afraid you have to change it yes or yes. If you are lucky that your model is the naked round headlight, you can save yourself the change.

The original headlight is large, and personally I think that replacing it with one that is too small does not suit a motorcycle like the K100, with an engine that gives it that powerful motorcycle image.

I recommend this round 8 inch (20 cm diameter) headlight , big enough for a motorcycle like the K100.


The K100, and even more so the K75, have fairly raised handlebars. They are touring motorcycles that prioritize comfort when driving.

We are going to give it a more aggressive touch, without sacrificing comfort. That is why we have selected a tracker type handlebar , which is not flat but is much lower than the original. We love the middle strap.

Handlebar BMW K100 cafe racer

By the way, for the cuffs, we have chosen these lozenge browns .

Rear-view mirror

We have opted for two under-fist mirrors , they are much more discreet and the result is spectacular.

Mirror under handlebar approved cafe racer 7


Needless to say, the dashboard of a BMW K100 is horrible. Yes, it’s very eighties, I’m not going to deny it, but it’s time to change it.

We have chosen a totally classic round one , which goes perfectly with the handlebar that we want to mount.

speedometer BMW K100 coffee Racer

Fuel tank

The fuel tank of the BMW K100 and the BMW K75 is not as classic and aesthetic as that of the boxer models. By having the shape lowered to place the knees, there is a cut in its line that is not too showy in a transformation. However, most choose to keep it, I leave you a magnificent example.

BMW K100 cafe Racer original tank
BMW K101 Gatermann

If you dare with a change, I recommend something more classic and rounded, a Honda type seat . It is not too expensive, and it totally changes the line of the bike.

BMW K100 by Ed Turner (1)
BMW K100 by Ed Turner

Seat and subframe

We are going to change the seat yes or yes. That ugly two-tier two-seat seat isn’t compatible with a Cafe Racer transformation.

The chassis of the BMW K100 is the same as that of the BMW K75 and we are going to cut it where I indicate in the drawing. From there we will weld a flat subframe in which to install the seat of our choice.

Cut Chassis BMW K100
Cut-off limit point on a BMW K100 or BMW K75

If it is more comfortable, you can cut at any other point as long as it is further to the rear of the red arrows, and weld a steel U. You must always respect the anchor of the rear shock absorber.

We have chosen a brown seat with a fiber tail , which we think suits you perfectly.

Hageman Motorcycles seat
Hageman Motorcycles


If you are lucky enough to have the naked model of the K100, you will not have to remove the fairing, beyond the side covers. The model with the fairing, very 80s, is amazing, but it has nothing to do with a Cafe Racer. It’s time to remove it.


Changing the tires of a Cafe Racer is always one of the aspects that generates the most doubts.

If you have a BMW K100 or a BMW K75 and you want to change the tires, I leave you several options compatible with their original measurements, an option in classic tires and another in Off-road tires.

 Series *Classic equivalentOff-road tire
Forward100/90 -R18Avon AM26 Roadrider 90/90 D18 51VHeidenau K60 90/90 D18 51S
Rear130/90 -R17Avon AM26 Roadrider 120/90 D17 64VHeidenau K60 Scout 120/90 D17 64T

Avon RoadriderAM26
Avon AM26
Heidenau K60
Heidenau K60


Whether you have the BMW K100 or the BMW K75 I am afraid you have to change the fender. There is no way to pick up those plastic monsters.

For the front fender I recommend a small plastic one . This one comes in black, but you can paint it the same color as the tank.

Black front fender

For the rear fender you have two options, or not to put any (the seat and the license plate are allowed to act as rear fenders), or place one on the wheel , which is worth to place the license plate.

Mudguards for Cafe Racer

Turn signals

The BMW K100 and the BMW K75 have the same turn signals, four large orange square devices. We can’t blame BMW, they were all the rage in the 80s, but not anymore.

We cannot do without the turn signals, we have to install all 4, but we are going to choose the smallest ones allowed by the regulations.

Turn signals BMW K100

My favorites are these small round chrome turn signals , but they are not cheap, so I leave you another much cheaper option , which are the ones we use in our 125cc Cafe Racer, Torrefacta .

And if you want to reduce it to a minimum, I recommend these indicators , which you will hardly notice.

Approved motorcycle fist indicator

Rear light

If we have decided to reduce all the optics to the maximum, we cannot keep the large rectangular rear light that this motorcycle rides as standard. I usually recommend a small circular one that already includes a license plate holder .

Cheap cafe racer taillight


We love this exhaust chosen by Retrorides for their BMW K100 Cafe Racer.

K100 Retrorides
K100 Retrorides

This is it, they are our suggestions to transform a BMW K100 Cafe Racer, or a BMW K75 Cafe Racer. They are just ideas to support you with your project. The best options are always the ones you like the most.

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