Using motorcycle drive belts from BEHIND an engine

Discussion in 'General Auto Conversion Discussion' started by Doggzilla, Sep 14, 2019.

Help Support HomeBuiltAirplanes Forum by donating:

  1. Sep 20, 2019 #21

    RSD

    RSD

    RSD

    Well-Known Member

    Joined:
    May 20, 2019
    Messages:
    162
    Likes Received:
    31
    OK. Just wasn't sure if it would handle 700 shp at 8700 rpm
     
  2. Sep 20, 2019 #22

    Rik-

    Rik-

    Rik-

    Well-Known Member

    Joined:
    Sep 14, 2019
    Messages:
    166
    Likes Received:
    21
    Location:
    California
    They handle thousands of HP turning a blower.. they can handle 700 hp especially when it’s low torque, 422 ft/lbs
     
  3. Sep 20, 2019 #23

    RSD

    RSD

    RSD

    Well-Known Member

    Joined:
    May 20, 2019
    Messages:
    162
    Likes Received:
    31
    OK that sounds promising
     
  4. Sep 20, 2019 #24

    Hephaestus

    Hephaestus

    Hephaestus

    Well-Known Member

    Joined:
    Jun 25, 2014
    Messages:
    1,125
    Likes Received:
    244
    Location:
    YMM
    So who's doing the analysis so we can start building? :)

    Insane 4am thoughts with a teething kiddo waking me up early... Since you'd have a hollow shaft running right between the heads - could you leave the point of the spinner open and use it to 'duct' cooling air straight to the heads?
     
  5. Sep 20, 2019 #25

    Rik-

    Rik-

    Rik-

    Well-Known Member

    Joined:
    Sep 14, 2019
    Messages:
    166
    Likes Received:
    21
    Location:
    California
    what Engine are you planning upon using?
     
  6. Sep 20, 2019 #26

    spaschke

    spaschke

    spaschke

    Well-Known Member

    Joined:
    Oct 24, 2012
    Messages:
    228
    Likes Received:
    53
    Location:
    Denver, CO
    NW Aero Performance and Belted Air Drives both used the Blanton design with their V8 packages. THere has also been some one off copies of the Blanton design. They've been running since the 80's. They are/ need to be very sturdy, which translates to a bit heavy. If they are not adjusted/tensioned properly, the belt will move toward one edge and shred itself. Mine uses a 12248M12k which around 4.5" wide. There are several companies that make the belts. The belts should be replace every 2 years or sooner if they show wear. They have plenty of strength.
     
  7. Sep 20, 2019 #27

    RSD

    RSD

    RSD

    Well-Known Member

    Joined:
    May 20, 2019
    Messages:
    162
    Likes Received:
    31
    Mazda Rotary 20B
     
  8. Sep 20, 2019 #28

    RSD

    RSD

    RSD

    Well-Known Member

    Joined:
    May 20, 2019
    Messages:
    162
    Likes Received:
    31
    is the Blanton Design a similar belt to the Gilmer Belts?
     
  9. Sep 20, 2019 #29

    Rik-

    Rik-

    Rik-

    Well-Known Member

    Joined:
    Sep 14, 2019
    Messages:
    166
    Likes Received:
    21
    Location:
    California
  10. Sep 21, 2019 #30

    AdrianS

    AdrianS

    AdrianS

    Well-Known Member

    Joined:
    Jul 5, 2014
    Messages:
    338
    Likes Received:
    193
    Location:
    Australia
    Do you mean they are used to spin the blower on thousand horsepower engines, using a couple of hundred hp max?
    If not, please provide a link to the "thousands of hp" belt drive.
     
  11. Sep 21, 2019 #31

    BJC

    BJC

    BJC

    Well-Known Member

    Joined:
    Oct 7, 2013
    Messages:
    9,486
    Likes Received:
    6,241
    Location:
    97FL, Florida, USA
    About 1,000 HP delivered into the blower by the belt drive, about 10,000 HP out of the engine.

    TBO of 5 seconds at power.


    BJC
     
  12. Sep 21, 2019 #32

    Rik-

    Rik-

    Rik-

    Well-Known Member

    Joined:
    Sep 14, 2019
    Messages:
    166
    Likes Received:
    21
    Location:
    California
    Actually the blower consumes about 2-3,000 hp. The net is greater with the blower but it takes power to make power.
     
    BJC likes this.
  13. Sep 21, 2019 #33

    RSD

    RSD

    RSD

    Well-Known Member

    Joined:
    May 20, 2019
    Messages:
    162
    Likes Received:
    31
    OK I've just realised that you are referring to a supercharger not a snow blower!
     
  14. Sep 21, 2019 #34

    Rik-

    Rik-

    Rik-

    Well-Known Member

    Joined:
    Sep 14, 2019
    Messages:
    166
    Likes Received:
    21
    Location:
    California
    Exactly. I’ll dig up a photo of how we did it in the boat and see if I can post it.
     
  15. Sep 22, 2019 #35

    pfarber

    pfarber

    pfarber

    Well-Known Member

    Joined:
    Feb 21, 2019
    Messages:
    218
    Likes Received:
    13
    Location:
    Pennsylvania
    Yeah but the motor was always under-powered (40hp) and when Hirth had a suitable 70hp motor they went bankrupt and most of those engines never got delivered.

    That was my meaning. Where there TV issues as well? Yes. But ASIDE from that the motors simply never performed, or were never delivered.
     
  16. Sep 22, 2019 #36

    pfarber

    pfarber

    pfarber

    Well-Known Member

    Joined:
    Feb 21, 2019
    Messages:
    218
    Likes Received:
    13
    Location:
    Pennsylvania
    And I agree that this is almost always the 'E'xperimental part of E/AB rearing its head. Lots of early failures in design, not the underlying concept.
     
  17. Sep 23, 2019 #37

    spaschke

    spaschke

    spaschke

    Well-Known Member

    Joined:
    Oct 24, 2012
    Messages:
    228
    Likes Received:
    53
    Location:
    Denver, CO
    Yes. Gilmer Belts had trapezoidal teeth, The belt I have has round teeth.
     
  18. Sep 23, 2019 #38

    pfarber

    pfarber

    pfarber

    Well-Known Member

    Joined:
    Feb 21, 2019
    Messages:
    218
    Likes Received:
    13
    Location:
    Pennsylvania
    As for the drive shaft I think you could get a bigger head start using a motor that already has a countershaft in the design (many 90deg engines need a countershaft to help reduce vibrations).

    This means that the block is already drilled for oil passages and the block ends already have a thick hunk of metal line bored for a sizable shaft.

    Auto engines are not about weight savings. You really can't save that much weight. Auto engines are about saving money on the initial purchase and maintenance (and rebuild).

    I'll happily give up 100lbs for a motor I can actually afford to run and maintain.
     
  19. Sep 23, 2019 #39

    Jay Kempf

    Jay Kempf

    Jay Kempf

    Well-Known Member

    Joined:
    Apr 13, 2009
    Messages:
    3,635
    Likes Received:
    913
    Location:
    Warren, VT USA
    Gates Powergrip HTD belts (the latest versions) have round teeth in round sprocket grooves. Supposed to run cooler, and quieter and transmits more torque as the failure is to shear the base of the tooth off which is much larger than trapezoidal. I have seen a trend toward these belts in timing belts.

    Don't ever say airplane around anyone from Gates or any of their suppliers. Say garden tractor.

    Used them on pretty high horsepower blower test rigs. They are stout! If you run them well below spec and cool them well they have quite good life.
     
    delta likes this.
  20. Sep 23, 2019 #40

    pictsidhe

    pictsidhe

    pictsidhe

    Well-Known Member

    Joined:
    Jul 15, 2014
    Messages:
    6,680
    Likes Received:
    1,760
    Location:
    North Carolina
    GT series are the successors to HTD with GT carbon being the highest power rated yet. More power and life, less noise.
    Designing a belt reduction for X hp is the easy part. Download the catalogue from your favourite belt manufacturer and go through the sizing process. They have tables for hp per mm of width for various pulley sizes.
    Designing a redrive that does not have TV issues is much harder. That is not even hinted at in the catalogues.
     
    wsimpso1 likes this.

Share This Page

arrow_white