1. carl clack

    I Blew My First Motor wanna See?

    This is what happens when you race on the streets, definitely my fault i knew it need to cool down and i forced it - i ride my bike daily 13 miles each way back and forth but this day i did the most and this was the outcome - these are really good motors that can really take a beaten with the...
  2. D

    Mixing cylinder bodies?

    Hi all, I picked up a PK-style lower end (Z-L rod/low wrist pin piston combo) and I was wondering if anyone has ever made a GT5 cyl/head work on this bottom end with extra base gaskets? Or are the port timings too far off between the two? Looking to see if anyone has had success with this combo...
  3. M

    GT5 vs No Name, stroke?

    Just surfing various motorized bike websites and read somewhere that GT5 engines have a shorter stroke? 38 mm vs 40 for the other engines. Is there a significant difference power? More importantly, with the smaller stroke does the GT5 have a higher redline? Just trying to narrow down the...
  4. Ruby478

    this may be a dumb question

    Whats the difference between a grubee sky gt5 and the gt5-A?
  5. A

    Grubee Skyhawk GT5 or SD Stinger?

    Which engine lasts longer and is higher quality?
  6. PatTheThird

    GT-5 bogs down at higher RPM

    I've had this gt-5 for a few months now. It starts imediatelly and idles great. For some reason once i reach an RPM range the motor backs off like its loosing fuel\air. I think there is a leak in my air intake somewhere. I have a carb ring from Sick Bike Parts and the intake itself is air tight...