How do I make my Buddy 50 or Roughhouse 50 faster?? 
   Open up the exhaust port, by removing the restriction cast inside. You need to remove quite a bit of material and then polish the surface. The exhaust port is also widened slightly at the opening to allow more flow and smooth out the rough spots.  All the bikes we have done this too have worked great, a lot more power and speed at all rpm's.  A very reliable change that will not require any other mods to the bike and give an instant improvement.

Roughhouse 50 and Buddy 50  cylinder modification

Stock cylinder for Buddy 50 and Roughhouse 50
modified cylinder. Note opened exhaust port  for more flow.
    This is good for around 5-6 mph on top end, and a lot more power overall. Better pickup off the line, higher top speed performance. Stock bore, use stock piston and rings. A must if you plan on using an expansion chamber to get the full benefit of the chamber. After this mod, you may not even need or want to change the exhaust.      
This mod works on many other models also,  Zuma, Vino, just a couple that use this type of restriction.
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