BMW G650X Cross/Challenge/Country/Moto Suspension Modifications
One of our favourite 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.
BMW G650X (All) 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 & heavier grade Oil - Not a perfect answer but better than stock. Stock springs are 0.48kg/mm, and we have rates from 0.44 to 0.85kg/mm in our 19-145 Series Fork Springs.
- Marzocchi Shiver Conversion - Since Marzocchi went bust in 2015 the parts are too hard to get and too old to make this conversion viable for us anymore. We used take a set of Marzocchi Shiver MX or Offroad Forks with compression and rebound adjustment and graft them into the G650 fork. We'd change the fork springs from progressive rates to linear too, making the front end more predictable. It required complete revalving of the cartridge internals, delicate machining of the axle feet feet for the compression adjuster too, and lacked an external spring preload adjuster.
It was a massive step up from stock, but takes a lot of money and a lot of time and effort to collect all the bits and pieces needed, so we won't be doing any more.
HiCalibre Fork Springs 40.2 x 462 Common Fitment S
Proudly made in the USA(SKU: 19-145)
From
$245.00
BMW G650X (All) Shock
The X Country has a traditional coil spring shock; a basic unit with ride height adjustment, giving between 330-338mm length.
The 650 X Challenge however 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. The air shock has a 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.
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 a 105N range (depending on rider weight and terrain/type of riding).
Rider Weight | BMW Suggested Pressure | Spring Test Results |
---|---|---|
70kg | 90psi | 7.4kg/mm |
100kg | 110psi | 9.1kg/mm |
110kg | 115psi | 9.5kg/mm |
130kg | 130psi | 9.8kg/mm |
We'd recommend changing to a high quality aftermarket shock for the best results. Our replacement shocks from Yacugar and TFX offer adjustability, servicability and reliability over all of the BMW stock shock absorbers.