Are you sure unrestricting the exhaust will accomplish the desired goal of a faster top end?
Yes.
The modification I'm talking about is very common around here. That cone is confirmed as one of the limiters. It is not part of the unrestricted exhaust, and it does not provide needed backpressure. It just smothers the engine so it can't gain too much power. That, combined with a metal ring that prevents the CVT from fully extending, is enough to crudely limit the speed to about 45/50 km/h. Remove the cone and the ring and you can floor it to about 80/85 km/h with no other modifications (on two strokes; unmodified unrestricted four-strokes usually top out at 60/65).
Modern 50cc scooters, especially if four-stroke, usually have another limiter in the form of either an undersized carb needle or programming in the ECU. Mine has the normal needle and, being a nine year old model, doesn't
have an ECU, and thus can't be limited in this fashion.
As to determining if that's the case, does the scooter accelerate sharply all up to 45 km/h, and then the acceleration immediately dies at that speed? If so, then the scooter is using some sort of power cutoff determined by speed. If the scooter's acceleration dies off long before 45 km/h, and it gradually creeps up to that speed, then top speed is engine power limited, and what you're doing may work.
It does everything slowly. I've used it restricted for seven years thanks to my dad's paranoia. I wanted to sell it after getting the bike, but then I decided to keep it at my mom's place so I can use it there when I go back by train.
Since the scooter officially belongs to me now, I'm free to get it back to the state it should always have been in.
As for 45+ km/h being dangerous to the user, I think that depends upon the scooter design and the user. Some designs are great and can handle twice that speed. Others don't seem safe even at 30 km/h. (Note for US readers: 45 km/h = 28 mph)
That speed is generally unsafe, because scooters around here are commonly used in very heavy traffic. Not being able to go as fast as the rest of the cars on the road means you're being constantly overtaken, sometimes by large trucks which tend to move a lot of air. This is dangerous in and of itself; when you add the complete inability of restricted scooters to accelerate fast enough to get you out of tight spots, and the additional wear and general unreliability of restricted engines, it makes it clear why Italians never accepted the law and broke it from day one.
Fortunately, most cops are aware of this and don't give you trouble, and most insurance policies for mopeds have a clause that basically says they will pay even if the vehicle is not technically road legal. Which is good, because close to 100% of 50cc scooters and mopeds aren't.
I'd love to get whoever thought up this law and put them on a restricted scooter in a city tunnel during rush hour. Then, maybe, they'd understand how idiotic the restriction is.
Do the same to all the paranoid parents who think that slower speed is always a good thing and perhaps there would be no need for the whole restriction shenanigans.
The CVT transmission can usually be modified by changing springs/wedges/cams/rollers/etc to allow a better gear ratio for high speed. This is common in the atv world also as more and more of them are using a CVT tranny versus a geared one.
Many young boys not old enough to legally drive 125cc vehicles (you need to be 14 to drive 50cc, 16 for 125cc) apply further modifications to their scooters to make them even faster. They usually replace the carb, exhaust and CVT transmission, which by itself can get a scooter up to 100 km/h or more. And then there are the nutcases who go so far as to remove the whole cylinder and piston and replace them with 70/80cc ones, which gets the top speed up to 130/140 km/h.
I never wanted to do any of that, because a) it's dangerous, b) I have no need for such speeds in what is basically a tiny utility vehicle, and c) police have much less tolerance for scooters that are modified in ways other than simple unrestriction.
I just want the thing to go at normal traffic speed.
