Home Forums Tech Talk KPV/HPV Gearing for Apex


This topic contains 2 replies, has 3 voices, and was last updated by  Sebastian Bacon 4 years, 3 months ago.

  • Author
  • #51213

    Andrew Serrato

    Hi, all –

    I’m new to the EKN and southern California F100 community and was hoping some of you seasoned vets could provide a little insight on gearing a KPV/HPV for Apex in Perris, CA.

    Right now, my kart is set up with a HPV motor and a HPV 3 pipe. The HPV engine came with an 11 tooth on the clutch, and the Italkart manufacturer provided a 85 tooth sprocket as my “stock” sprokect. I’ve heard HPV 3 pipes  have a fairly strong bottom-end, and judging by some recent YouTube footage, it looks like Apex may require a gearing that provides a stronger top end for those long straight aways.

    I’m curious as to what gearing you’d seasoned vets would recommend. Thanks for the advice!

  • #51222

    Walt Gifford

    Never been to that track but if it’s about a 1/2 mile I’d try the 85 first then put on an 83. If it’s 1/4 mile I’d try an 87. If you feel it stop pullin’ 3/4 down the longest straight it’s about right.


    FAA certified jet engine and aircraft technician,
    Nicholson Speedway class champion 2001,
    Yamaha KT100 Service Center,
    41 years karting experience

  • #51242

    Sebastian Bacon


    If I remember correctly, I think I ran a 10/78 with a 3 pipe. This is about equivalent to an 11/85 or 11/86. So I think the 85 should work pretty well. I would start with the 85 and go from there.

    Hope this helps.


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