BMW GS history

BMW introduced the R80GS and R100 GS (for Gelände Sport, Gelände meaning something between "country" and "field" in German) in 1988, and the Paris-Dakar version in 1990. Starting in 1992, the Paris-Dakar was re-designated the PD due to some legal conflict with the organizers of the Paris-Dakar rally for which it was named.

Early GS
1988: The original GS had the fork-mounted instrument pod like the G/S with a small tombstone fairing around the headlight.
1990: The Paris-Dakar model was introduced as a modification of the base model, available from the factory or as an upgrade kit.
Late GS
1991: The bike was substantially updated, and the regular GS got a PD-style fairing.


The GS is introduced, replacing the G/S. The US got only the R100GS, but an R80GS was sold in other markets. The major differences between the R80GS and R100GS are:

The differences from the G/S are:

Model year differences

In 1988

In 1989

In 1990

Early (above) and late (below) levers

1990 Paris-Dakar

At first the components were only available as a kit, but for the 1990 model year the Paris-Dakar was introduced.

When the solo rack is retrofitted, the seat latch plate (with passenger grab handle) is removed from the subframe and installed on the front of the solo rack. PDs which shipped with the solo seat (not all did) had latch plates without a grab handle.

1991-on GS and PD

In 1991 the GS got the PD-style fairing, shaped differently to match the steel tank. The dashboard is altered for both models, now having a large speedometer and tachometer. The clock is available as an accessory that bolts onto the handlebar clamps (and looks terrible). The other major change is the switchgear; these bikes now have the pushbutton switches that were introduced on the K series. Other changes:

Fork/fender braces

The '88-90 bikes came with a simple curved brace 31 42 1 452 517 with four holes for mounting to the fork leg tabs. At first there was only a high fender, and for customers who wanted it mounted low there was a US-built brace which allowed this. In 1989 a low fender was offered, which attached to studs that were used in place of the regular bolts.

When the GS was updated in 1991, a new 8-hole brace 31 42 2 312 119 appeared. This spread out the mounting points for the fender, propably to reduce the paint cracking that had been common. The fender, of course, had holes that were spaced farther apart for this. The brake hose holder was also changed.

US-only brace for mounting the high fender low
8-hole brace


Gearing and speedometers

In general the 800cc models came with a 3.20 final drive ratio, and the 1000cc models had a 3.09. Those were the only gear ratios produced for the Paralever Airhead models. The earlier G/S had a 3.36. Different final drive ratios required different speedometer gearing, and often the faces were marked with different shift points.

All speedometers are marked with a W number (Wegdrehzahl, literally "path turning count" but more practically the speedometer ratio or coefficient), which represents the number of turns of the cable needed to accrue one mile or kilometer. The W roughly corresponds with the final drive ratio, although this is not mathematically consistent across all bikes. For each of the speedometers listed below, the intended FD ratio and the W are given.

We'll start with the G/S speedometers, just for perspective and because they are physically interchangeable. In compliance with US law, the '81 and '82 G/S speedometers for the USA had the required 85MPH max and the emphasis on 55MPH.

85MPH G/S speedo W1244
Rear view
120MPH G/S speedo W1244
Rear view

'88-90 GS speedometers were physically similar but had a larger housing and also were produced with lower W to match the taller final drives.

'88-90 GS speedo W1202
Rear view

With the dashboard redesign in 1991, mounting posts were added to the back of the speedometer. Although the final drive ratios did not change, the W were adjusted downward slightly.

'91-on GS speedo 1144
Rear view

For reference, the Roadster kept the same W as the GS but the cable angle was different so they have different part numbers. It may be possible to install one of these in a GS if neeeded. None of these are still available new.

R100R rear

GS Sources:

Replacement Valeo starters: (also read the rebuilding article)
Bob Spencer
Ace Houston Warehouse
Their part# 432586, was D6RA15

Replacement fork parts:
Forking by Frank:
Frank's Maintenance and Engineering, Inc.
Phone: (847) 475-1003

GS links:

Jean Moxhet's GS website on Micapeak

Scot's R100GS page

Joerg Hau's GS pages