Often overlooked when upgrading, the Electrical Circuitry in your buggy runs everything from the Engine to the Lights. The Stock CDI is simply not very efficient. Performance can be significantly improved by Upgrading the CDI.
A Performance CDI can increase your RPM's by eliminating the "rev-limiter" found in most Stock CDIs. This CN250 CDI will allow you to achieve over 1000 additional RPM's. That's a significant performance upgrade that should not be overlooked. You can also advance or retard your timing on both the GY6150 & CN250 versions of this CDI.
Performance coils provide a Stronger and more Consistant Spark. A faulty Coil is a common cause of "sputtering top end", in a buggy.
A voltage stabilizer will work wonders on a slow to start buggy by "amping up" the juice on ignition and providing a constant flow of electricity and a smooth top end performance.