Aus das GS 500 Wiki: www.GS-500.info
This is the documentation of how I changed the forks on my GS 500 to the USD forks of the RGV 250.
This documentation is thought as a support, I can't guarantee that it will work on your bike. I don't take any responsibility if it doesn't!
Parts list
- one complete RGV 250 forks
- wheel RGV 250
- axis with distances and speedo-wheel RGV 250
- complete front brake system RGV 250
- top and bottom yoke RGV 250
- front mudguard RGV 250
- a new bearing for the steering head (original GS 500)
- an ignition lock of the GS
- a set of clamping pedestrials and a handlebar OR handlebars you can attach to the forks (e.g. RGV 250)
- a steering stop limit
- A distance ring that goes under the lower bearing for the steering head:
Measurements:
inner diameter 30 mm
outer diameter 54 mm
thickness 8 mm
NB: The thickness of the ring can vary. It's best to measure it on your own frame.
 Yoke, distance ring, steering head bearing, steering stop limit |
Conversion of the lower yolk
- Remove lower bearing for the steering head. I used a Dremel, others use an angle grinder.
Be careful not to damage the pole duct!
- Put the distance ring on the pole duct. If you use a slightly bigger duct and a rubber-hammer, it's a piece of cake. (You don't have to use German beer, it's just an example. ;) )
- Now you have to get the lower bearing for the steering head on the pole duct, another duct is handy as well. It can be done with a bolt as well, just be careful not to damage the bearing.
The ”new“ bottom yoke is done.
 pole duct without bearing |
 pole duct with distance ring and "liquid power" |
 pole duct with added bearing |
Conversion of the steering stop limit
I cut the old steering stop limit down to 5mm, adjusted the new one with the new bottom yoke and welded a few spots to fixate it. Then I put the new yoke out and the old GS yoke in to stabile the bearing carrier during the final welding.
Now weld the steering stop to the frame.
 welded new steering stop limit |
 planed welding (just optical) |
Another possibility is to weld the new steering stop limit under the old one – that obviously influences the thickness of the distance ring.
Conversion of the ignition lock holder
- Detach the old holder carefully with a Dremel.
- Put the GS yolk with the ignition lock back into place and measure the size needed.
- Then grind the lock holder to the right size. I attached the holder to the upper yolk and welded some spots.
- Now put the old GS yolk back in and carefully weld the ignition lock holder.
- Mask the vehicle identification number and prime the stearing head (after it cooled down).
Putting everything together
After priming (or painting), attach the upper yolk, then the forks and the wheel.
When you attach the brake, it may be possible that the hoses appear to short if you haven't got a motor in the frame. With a motor, everything should be fine. Just make sure that the roses aren't under excessive pressure when the forks are completely without tension - they might rupture otherwise!
The handlebar
This requires a bit of creativity.
One option is to get an accessory top yolk which already has bearings for a steering wheel.
Also you can attach the handle bars to the forks.
Finally you can put holes in the RGV yolk (there are already 2 points where the original RGV instruments attach, you could drill through the middle ones) and attach the bearings.
NB: This option might compromise the stability of the yolk, so think about the other options before doing this!!!
Finally: I haven't used a RGV wheel, instead I used a RF 600 wheel. This one has 3.5“ and can take a 120 tyre! There are also other possible wheels (GERMAN) that fit to the RGV forks.
