Harley-Davidson Screaming Eagle Tappets May Increase Durability By 25%

New Screamin’ Eagle® Tappets (P/N 18572-13, $249.95) from Harley-Davidson® Genuine Motor Accessories® are designed to deliver superior tappet life in high-performance Harley-Davidson Twin Cam and Sportster engine applications. Large, high-capacity needles in the roller bearing assembly improve reliability when operating with high-lift cams, high-pressure valve springs, and in high-RPM applications.

The needle bearings are 25 percent larger to increase the dynamic load rating by approximately 20 percent when compared to the Original Equipment Twin Cam tappets. Sold in a set of four, these Screamin’ Eagle tappets may be used in 1999-later Twin Cam engines, and in 2000-later Sportster Evolution engines. Harley-Davidson.

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9 Responses to “Harley-Davidson Screaming Eagle Tappets May Increase Durability By 25%”


  1. 1 Chris Nov 1st, 2013 at 8:18 am

    I’m no mechanical engineer, but this smells fishy. Sure, each individual bearing may have a 20% greater load rating, but with fewer rollers, there is more load per roller. Also, just like with a big axle lifter,the larger roller is going to spin faster.

    Again, I’m no engineer and I’m hoping somebody can educate me here and convince me that I’m wrong.

  2. 2 Woody's Nov 1st, 2013 at 10:06 am

    In this application the load isn’t on all the the rollers, just the ones in the line of force, so with either one you only have 2-3 rollers taking virtually the entire force applied. This will be a running change because continuous improvement is H-Ds goal, right? 😉

  3. 3 1550tc Nov 1st, 2013 at 8:32 pm

    The ones from Bobby Wood are the way to go !

    http://www.woodcarbs.com/dirlifters.htm

  4. 4 rob Nov 1st, 2013 at 10:17 pm

    I’ll stick with S&S or Feuling…………

  5. 5 jim Nov 2nd, 2013 at 7:54 am

    I see no need to go away from Fueling!!!!!

  6. 6 Industry guy Nov 3rd, 2013 at 10:45 pm

    Overhung bearings = Unequal load on Needle bearings and inner race. Good luck guys.

  7. 7 kevin boyle kustoms Nov 4th, 2013 at 3:33 pm

    I use woods directional lifters on ALL my tc builds or repairs along with his valve springs…

  8. 8 AX Nov 4th, 2013 at 9:42 pm

    “…because continuous improvement is H-Ds goal, right?”
    Good one.

  9. 9 montcwby Jan 18th, 2014 at 9:16 pm

    @Industry guy– They aren’t overhung bearings, they are just cut away in the pictures so you can see
    the needles. I’ll go with Fueling though, until I hear that nobody has any problems with these HC lifters.

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