Results 1 to 8 of 8

Thread: Camshaft

  1. #1
    Join Date
    Dec 2018
    Posts
    36

    Camshaft

    What is the biggest dyno cam i can go with and still use a pull start..

  2. #2
    Join Date
    Oct 2013
    Location
    Linden, IN
    Posts
    9,628
    Depends on how strong your arm/fingers are (and how strong the pull rope is.)

    Personally, I'm not a fan of pull starting a WKA legal motor (which has a small compression release.)


    I suspect you could pull start most of the cheater stock cams with no compression release, but why would you want to?
    Electric starts are relatively inexpensive and you can get your wife or kids to start the engine without hurting them.

    If you absolutely must pull start, then you might consider installing a compression release in the head for use just while starting - this is more common on the higher compression 4-strokes.

    -----
    Thanks and God bless,
    Brian Carlson
    Carlson Racing Engines
    Vector Cutz
    www.CarlsonMotorsports.com
    Carlson Motorsports on Facebook
    30 years of service to the karting industry
    Linden, IN
    765-339-4407
    bcarlson@CarlsonMotorsports.com

  3. #3
    Join Date
    Oct 2013
    Location
    Florence
    Posts
    376
    There is one cam that comes to mind. If I remember correctly You are running this on mini bike or fun kart?
    It was a .300 lift designed for the old raptor super stock class had tons of duration. Cam lobe was almost flat across the top of the lobe. If you can find one it would work well. I sure someone on here has one.

  4. #4
    Join Date
    Oct 2013
    Location
    iowa
    Posts
    6,739
    The two I've pull started are the 107ss and the 110 drag. Ignition timing is critical , not too much. It only took one back stroke on the 107 ss for me to buy an electric starter.
    The in head compression release would be a good option.
    Dyno cams may be able to grind an ez start on the cams , you would need to call them.
    I wouldn't recommend any cam with out ez start especially on a mini bike .
    Dont know where your at but if in the snow belt look for a tecumseh hm 10 or maybe 8 they are bigger hp to start.
    Or even go to big valves on the Briggs engine .
    The high lift cams going to be a real painful pull start.
    Last edited by flattop1; 01-26-2019 at 11:23 AM. Reason: Predictive text

  5. #5
    Join Date
    Oct 2013
    Location
    15 Anne St. Springfield, Mass.
    Posts
    347
    I don't know why everyone is assuming this is a minibike project but if it is you really would not want a huge racing cam. Camshaft choice is always a compromise, big racing cams are designed to make power at high rpms and they sacrifice torque at low rpms. Chances are that the "biggest" cam you really want is a cheater cam with the ez spin intact. Call dyno and I am sure they would be happy to recommend a cam that best suits your needs.

  6. #6
    Join Date
    Oct 2013
    Location
    Florence
    Posts
    376
    One thing I have learned about Dyno Cams and others are that if you call them, They will help you. And probably have what you need.

  7. #7
    Join Date
    Dec 2018
    Posts
    36
    This flathead motor will be on a minibike and we use them for drag style runs 1/8 mile.it will be setup for high rpm revving.it will use a disc clutch 3000 rpm stall.which cam would do the best torque wise but not give up that top end.only cams that i use is 94ss.its good but i know theres a better one out there.
    I still wanna use pull start though.lol i know im a dumb***
    Or until i can find me a starter box cheap enough...

  8. #8
    Join Date
    Oct 2013
    Location
    iowa
    Posts
    6,739
    112 alt
    Anything bigger then the 94ss is going to require modifications to obtain clearance for valves , lifters and crank counter weight .

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •