How to Make Your 49cc X5 Pocket Bike Go Faster

With your X5 capable of doing 45 MPH right out of the box, it's no wonder these little bikes are growing in popularity. You can buy one from a few hundred dollars to several thousand dollars, and with the right parts, they can generate speeds of up to 78 MPH. While most modifications can be done by the weekend mechanic, some modifications may involve a bit more technical expertise and skill.

Things You'll Need

  • Aftermarket exhaust
  • Aftermarket clutch
  • Aftermarket air filter
  • Aftermarket spark plug
  • Ratchet set
  • Screwdriver
  • Shop rags
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Instructions

    • 1

      Add an aftermarket high performance exhaust system by first removing the plastic body covering your bike. Locate the header bolts by following the exhaust to the front of the motor. Unbolt the exhaust and remove it. Install the new aftermarket exhaust and replace the header bolts. A high output exhaust system is a must for any high speed applications. It gives your bike more power through all of the RPM range, and with its wider and longer expansion chamber creates less back pressure in the exhaust--which allows your bike's engine to move the exhaust out faster for that extra boost of top end speed.

    • 2

      Replace the stock clutch with an aftermarket racing clutch. This modification will take a bit more technical prowess and require a mechanic to properly install. However, replacing your stock clutch is recommended for two reasons. First, these clutches are built to higher specifications and can tolerate your higher RPM racing starts that are sure to cause the death of any factory clutch. Second, most aftermarket clutches are designed to engage at a higher RPM, between 1,000 to 2,500, giving you an increased amount of acceleration where power is most needed to get you off the line faster.

    • 3

      Locate and remove the old restrictive stock air filter by unscrewing the clamp holding it on and replace it with a new free flow, high performance one. Then use a socket wrench to remove your old spark plug. Simply unscrew the old one and replace it with a high performance one. With these changes, you will provide a better flow of air into your motor and more spark, resulting in an increased amount of fuel into the air flow. This will provide you with a richer mixture and balance out the system, giving you the most power throughout your RPM range.

    • 4

      Check and re-tighten all of the bolts on the parts that you replaced. Once you are sure that everything is installed correctly, reinstall the plastic body covering onto the bike, then grab your helmet and take your bike on a short test run to ensure everything is running smoothly before opening up the throttle to test the speed.