replace the stock CDI with a performance (orange or blue) CDI, make sure you get the right one, some are AC and some are DC.
the rev limiter is built into the CDI, you can get a CDI without the limiter on ebay.
on 5occ - 150cc gy6 qmb or qmj engines the rev limiter is part of the cdi programming.
In the battery box. you will see it unplug it
Generally the electronic ignition module limits the rpm Hi performance modules are available without limiter.
CDI box
Get the wiring diagram for your bike. I downloaded a great tank gy6 service manual that matched both my 50cc 4-stroke tank and baja scooters. I found CDI modules had a yellow and green wire going to something called speed selectable unit... I assumed a rev limiter. I diconneted the wires to it first. The bike didnt run.Then I tried connecting the green and yellow wires together, bypassing the rev limiter, and it worked great, so i did it to both bikes.
Yes you can get a rev limiter. You can buy them from Scooter Attack dot com.
The rev limiter is part of the engine computer programming. The computer would need reprogrammed to change the rev limiter.
Not at all, is it not illegal to reprogram or even remove a rev limiter, however it may affect your warranty etc.
it has a governor or rev limiter which is there so you don't blow the engine up and the minibike is probably topped out on top speed at 70 anyways
The rev limiter on the 2005 Sportster is built into the ignition module. It is not possible to remove it. You can upgrade your module to "after market" modules that can increase your rev limits to 6000 RPMs and beyond.
The rev limiter is part of the computer programming.