Ideally your bike needs to be on a decent well supported centre lift stand as the front wheel needs to be clear of the ground to drop the bottom yoke & stem. This is my bike shown and its fitted with the US headlight and a digital trip computer but these instructions should apply for any version of headlight/Speedo etc. My bike is a 2002 model and I don't think the bearings have ever been touched before; was surprised to find them in such good condition.

Remove the headlight and disconnect the wiring to the bulb holder.

Disconnect the Speedo cable

Using a 30mm ring spanner slacken and remove the top headstock nut (anti-clockwise) it is tight but nothing a bit of muscle won't shift.

Next screw the removed bolts into the top clamp from the opposite side; now using a couple of pieces of steel slide these into the gap and tighten the bolts onto them, this will press on the opposite side and open the fork clamps very lightly so the top clamp can be lifted off.

DON'T OVER TIGHTEN THESE BOLTS YOU WILL BUST SOMETHING !!!

Now the top yoke can be lifted away, exposing the stem nut; it won't go far due to the cables etc but you don't need a lot of room.

With the nut removed the headstock will simply drop away this is why you need the block !!! You can now see the lower bearing, you won't need much space to re-grease and the bearing cage will spin around so getting the rollers greased up is a doddle.

Now you can use whatever grease you like on your bike but I am sticking with a general purpose LM grease, some may feel the need for water proof grease but that's your choice...my bike doesn't get wet.

Applying the grease to your finger first is the easiest way, and using your other hand you can spin the bearing around and let the grease rub into the rollers.

Place the freshly greased bearing back into the top outer race; followed by the seal.

Tricky part and a bit hard to explain but you need to lift front wheel assembly upwards or carefully lower the bike downwards to engage the stem into the top bearing without knocking the bearing or seal out, don't worry if you do just make sure everything is engaged fully before putting the bottom nut on. Once your happy everything is back as it should be screw the bottom nut all the way home and then you will need to tighten it with your "C" spanner or punch, tighten down till it goes firm but keep checking the handlebars turn freely and don't bind or appear loose. Then once your happy you can place the top yoke back over the stem and put the washer on first followed by the top nut and tighten. Remove the 2 bolts holding the top yoke  clamps apart and reverse these and tighten don't over tighten these as you either crack the top yoke or pull the threads out.