The Kneeslider

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1947 Water Cooled Drake Harley Davidson Knucklehead Engine

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Drake water cooled Harley Davidson engine
Drake water cooled Harley Davidson engine

A couple of years ago, there was a midget racer with a Drake water cooled Harley Davidson engine for sale. The car looked really nice but you could barely see the engine. I just noticed, there is another one of these for sale, but this time the car is all apart and the engine is shown very clearly.

The cylinders are completely covered in water jackets with all of the associated plumbing necessary to carry the coolant. You have to wonder, with all of the strict emission controls on engines these days and the difficulties that come with keeping an air cooled engine clean, maybe Harley could just go back to the Drake. Sure would save on engineering costs. ... Only kidding!

Drake water cooled Harley Davidson engine
Drake water cooled Harley Davidson engine
Drake water cooled Harley Davidson engine
Drake water cooled Harley Davidson engine
Drake water cooled Harley Davidson engine
Drake water cooled Harley Davidson engine

Posted on Filed Under: American Motorcycles, Engines

Comments

  1. Cool stuff! But you forgot the part where H-D sells the water jackets and radiator as an after market (screaming eagle) accessory for only $4,999! (I think I joking, or I hope I am!) he he. oh well time to practicing the welding! Thanks Paul!

  4. First I’ll say I am a Harley owner and I love my Street Glide. However, engineering was never a strong point with Harley Davidson. I’ve asked this question to numerous Harley dealers, mechanics, and even at a manufacturing plant. Why is Harley still making the “A” motor? And, why is an unbalanced motor in their touring bikes? With all the financial problems they are facing, why not eliminate it altogether.

  5. BMW make air cooled engines that pass all noise regulations, and so did S&S with their new v-twin. No problem….

  6. “maybe Harley could just go back to the Drake. Sure would save on engineering costs. … ”

    Are you sure? bidding is at 15,000+… what were you thinking Harley would spend on engineering?

    Just kidding…

  7. considering they didn’t know how much killing Buell would save them, would HD know how much the Drake would save them in R&D?

    “heckles” was part of the reCaptcha 🙂

  8. “maybe Harley could just go back to the Drake. Sure would save on engineering costs. … ”

    Are you sure? How much do you think Harley spends on engineering, anyway?

    Just kidding… 😉

  9. The Drake midget engine was very competetive in it’s day. Even Vuckovich ran one. Willie G has a completely restored Drake midget in the center of his private collection. He loves it!

  10. Interesting. The jugs are easy to cool. but what about the heads? Those heads don’t look much different than an air cooled Harley. I don’t think it would really be necessary.

  11. Looks very similar to a 1920’s “Dog-eared” JAP engine. The kind you would see on Morgans. Only not so nice.

  12. I can only hope that if HD has to succumb to water cooling that the powerplant they design looks as cool as this modified knuckle.

  13. The heads are cast integral with the cylinders so the water jackets continue within. The rocker boxes look to be original H-D.

    Check out those tiny spindles and rotary shocks. Sweet.

    -todd

  14. *RaisingKane*

    What you fail to accept is that the A motor is actually the preferred choice of many, and the rubber-mounts smoothing the vibration is considered to be better than the mechanical noise and eerie stillness of the balanced motor, which – to some – is smooth as a Japanese V-twin and something they ride Harleys to avoid: it’s a personal preference and long may we be able to continue to express one. Oh, and the A motor is also infinitely more open to tuning, not having to deal with the balance factors.

    Will be interesting to see whether Harley recreate something like the Drake to take the long stroke, OHV motors into the next round of EPA compliance: a few cosmetic fins and somewhere cunning to hide the radiator, and they could end up with an acceptable stable-mate for the VR, with minimal retooling.

  15. Somebody had a pretty good idea of what he was doing back then! Both cylinder/heads have bosses to attach the engine mounting plate. Good planning that! Should help mounting it on your Morgan Trike! How’bout onto a VW or Hewland transaxle for a front-wheel-drive cyclecar?!

    That’s a trick little weight jacker on the front end. Just a 1/2″ drive ratchet with 2 links back to the pilot in the cockpit. Tune while you drive. Adjust when the track dries & the blue groove appears. Slick!

    Is Drake the same one who, with Meyer built the Offy engines after Fred Offenhauser retired?

  16. I just Googled “Drake Motorcycle Engine” & got several links to get more info & pics:–

    http://thekneeslider.com/archives/2008/06/09/drake-harley-davidson-water-cooled-v-twin-engine/ – Car driven by Bill Vukovich Sr

    http://thekneeslider.com/archives/2006/01/23/hotrodhawg-harley-powered-roadster/
    – Street rod powered by Harley engine

    http://www.beautyofspeed.com/gallery/motor_drake/index.htm – Other pics & a history lesson. Other V-twins built for Midget racing.

  18. American V

    Thank you for your candid response. However, I don’t fail to except that some may prefer the “A” motor over the “B.” Perhaps I overstepped by saying they should eliminate it altogether. In fact I think it would be the engine of choice in the Dyna line. Just a thought, when HD redesigned the touring frame, would have been a perfect time to change over. In talking with other tour bike riders, I have met a majority of riders that would trade in their touring models tomorrow if HD offered the B today.

  19. cap`s sandblasting and powdercoating had some new castings made here in fresno ca,jessy james tried to get his boney paws on them first ha ha ha the loser lost

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