April 18, 2016

how do i derestrict a sym city hopper?

hey iv just bought a sym city hopper and its restricted to 35 mph, anyone now how to derestrict it. thanks



I dont know ask a machanic


Derestricting a 50cc?
Well the very word derestrict would imply that there is some form of restriction on the engine, the question is what? Many manufacturers have a simple washer welded inside the exhaust-system which will restrict airflow and hence speed. Remove this and you should find a noticable difference. Alternatively, bin the standard exhaust and go for a performance exhaust system. However, this is not enough, you must replace the original jet from the carburator, for a bigger one for optimum performance.

Another restrictor is the automatic gears or variomatic. In the first part of the variomatic is a big ring which must be removed. The weights inside the variomatic are responsible for a balance between accelleration and top-speed. You must buy a set of those weights, so you can try to find this balance.

Last but not least, many Japanese scooters have electronic restrictors. In many cases you just need to cut the red wire, usually for models pre early 1990’s or you may need to replace the CDI unit on other models.

Aaron B


PM me your regular email address and ill send you a guide on how to de-restrict it. I used to have a City Hopper!


Tom Johnson

Could u pls forward me this email would be very thankful just got one of these myself!!


Can u email me the video as well please


Most scooters with the CVT transmission will have a spacer that limits the travel of the conical plates of the variator. This will then limit the speed. Theres a nice video series of tutorials posted here:
Also check out:

It will give you a good idea how the variator works and how it is restricted.

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