BMW G 650 X Moto        

The G650 range from BMW encompasses the X Challenge, X Country and X Moto. They all share the same platform but vary slightly. They have become something of a cult bike, becoming more popular since production ceased.

One of our favorite Motoradders Amy Harburg has our suspension in her G650X. She is a GS Girl; a member of the BMW Motorrad International GS Trophy Female Team, and has done extensive testing for us on her own G650X.

We will talk about all the G650 bikes as one, as they all share a similar platform. The X Country does come with 19/17 wheels and a 270mm travel fork, but it uses the same fork tubes as the X Challenge so all bikes can be made the same height.
Forks
The 45mm Marzocchi forks come in a few variants for the models but are all very similar internally. Inside they are very cheaply manufactured, using a crimped steel cartridge that cannot be disassembled, and therefore cannot be rebuilt, modified or repaired. They are very similar to the units found on the F800GS, and need the same kind of modifications.
  • Stiffer fork springs and heavier grade oil. Not a perfect answer but better than stock! We have spring rates from 0.44 to 0.85kg/mm. Find the rate you need HERE.


     

  • Shiver Conversion. We take a pair of used 45mm Marzocchi Shiver forks (from a motocross or enduro bike) and graft them into the G650 legs. This involves some delicate machining of the G650 fork axle feet to accept the compression adjuster housings. We also change fork springs, depending on your weight, and use linear springs rather than progressives. The transplanted cartridges are extensively re-valved for Adventure/offroad use and suspension dyno tested before fitting. Often we will swap the chrome tubes if your donor tubes are in better condition. Current cost for this conversion is $800 plus the donor forks plus any rebuild parts needed, like seals and wipers. Expect $200 to $400 for a set of suitable Shiver forks.


     

Shock
 

The 650 X Challenge has an air shock which is OK for light riding to the shops to get some milk and a paper but not much else. It wallows, tops out and has been known to leak. We have tested the stock air shock in our spring tester over BMW's suggested pressure range, with the lowest reading being 70N and the highest 95N, and we tend to use shock springs in the 80 to 105N range (depending on rider weight and terrain/type of riding). The X Challenge has an air shock length of 342mm, and whenever we fit a replacement shock to a G650, it's the length we use because we feel its the best length for the chassis.

Air spring stock pressures, weights and conversions from BMW stock data to us testing the stock air shock at varying pressures.
 

Rider Weight

BMW Suggested Pressure

Spring test results

70kg

90psi

7.4kg

100kg

110psi

9.1kg

110kg

115psi

9.5kg

130kg

130psi

9.8kg



The X Country's coil spring shock is a basic unit with ride height adjustment, giving between 330-338mm length.

We recommend an Ohlins BM636 as a coil spring replacement. We shorten this shock under normal circumstances to 342mm, same as the stock air shock.

Shaft Clamp - 20 24 28

Shaft Clamp - 20 24 28

93-004-02

$96.80

Shaft Clamp - 10 12 12.5 14 16 18

Shaft Clamp - 10 12 12.5 14 16 18

93-004-01

$96.80

Inner Slide Bush 45 x 20 x 1.5

Inner Slide Bush 45 x 20 x 1.5

24-640-00

$38.50

Fork Spring Compressor

Fork Spring Compressor

93-008-00

$247.50

Fork Seal Driver Kit

Fork Seal Driver Kit

93-009-00

$258.50

Fork Oil Level Tool

Fork Oil Level Tool

93-002-00

$49.50

Fork Dust Wipers 45mm id

Fork Dust Wipers 45mm id

24-891-20

$38.50

Bushing Driver Set

Bushing Driver Set

93-118-00

$174.90

45mm Marzocchi Fork Seal & Wiper Set

45mm Marzocchi Fork Seal & Wiper Set

24-891-00

$110.00

19-145 Motorcycle Fork Springs
RRP $218.90