No as there is a bearing in the housing with retainer clips. As I recall the shaft comes out of the top with the top retainer under the steering wheel. If you remove the steering wheel you can remove the clip...
OK so try this:
Buy a good penetrating oil. Many in the US use PB Blaster, I don’t know the trade names for similar products in the EU but do avoid WD40. You can make your own using automatic transmission oil, do a search for the correct recipe. If you can buy it remember premade in a can all the better.
- Loosen the nut on the steering wheel such that it is still on the shaft by at least three threads.
- Clean and the then lubricate the shaft where the splines and the steering wheel come together. Do this every evening and morning for a week. Keep riding your scooter.
After a week of letting these sit you can take the next step.
- I am assuming you have a steering lock, if not you will turn the wheel all the way to the left. Once against a stop, apply further rotational torque to the steering wheel against the stop. Now repeat the task in the opposite direction (if you have a steering lock then its just moving it a few degrees to the right). Repeat this a couple of times.
- Next, turn the wheel so the spokes of the wheel allow you to place the palm/flat of your hands on the back of the wheel with 7-10cm of space behind your hand (likely need to turn the wheel to avoid the levers)
- With the nut still on the shaft by at least three threads, hit the back of the wheel with both palms at the same time repeatedly. The more impact force you can apply the more likely to break it free, so the distance from your hand to another object becomes the issue here.
Repeat this several times.
If not successful, give it a few days with additional penetrating oil and repeat the above procedure.
Another approach:
- After letting it sit for a while with the nut loose and having lubricated the spline area with penetrating oil, grab a 1 kilo hammer or similar, a pointed round end chisel or ‘drift’
- With the nut still on the shaft by three threads
- Put the drift into the depression in the center of the shaft, apply pressure to the back of the steering wheel using your knees or a couple of friends.
- With the pressure on the back of the wheel, hit the end of the drift with a series of hard blows with the hammer.
This drives the shaft down and the springiness of the wheel will pop the two apart.
Always remember to keep the nut on the shaft to prevent having the wheel fly off and hitting you in the face, it has happened to several people. Not me, because I do follow some directions.
This group of tasks has worked for me on several other Fiats whose wheel had never been off in 40 years.
The last alternative is a puller but it is likely to damage the wheel.
Hope that helps.
Karl