Table of Contents
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IH: Carburetor, Intake Manifold & Exhaust
See also Installation of Top End for proper alignment of intake manifold.
Intake Manifold
HD Manifold Part Numbers | ||||
Year Model | Manifold Part# | Material | Throat Dia. | Bolt Hole Dims/Spacing |
1957-1971 Sportsters | 27021-57 | Cast iron | 1.562“ | .39” holes on a 2.688“ b.c. 1) |
1972-1974 Sportsters | 27021-71 | Cast iron | 1.562” | .33“ holes on 2.750” b.c. 2) |
1975-1979 Sportsters | 27021-71A | Aluminum | 1.562“ | .33” holes on a 2.750“ b.c. 3) |
1980-1985 Sportster | 27021-78 4) | Aluminum |
1975-1979 Sportster Intake Manifold 27021-71A 5) | ||
1980-1985 Sportster Intake Manifold 27021-78 6) | ||
Seals - Intake to Heads
Intake to Head - Hardware History. 7)8) | OEM Part Numbers | |
1957-78 | Used exact same port sealing machining, heads and manifolds | Uses O-rings - 27060-55 - Clamp 27063-57. |
1979 | Confusing because it had the o-ring machining but used rubber bands | Uses rubber bands - 27062-78 - Clamp 27063-78. |
1980-later | Made with “o-ring delete” machining. | Uses rubber bands - 27062-78 - Clamp 27063-78. |
1979 models could retro fit 78-earlier interface mechanisms as a bolt on mod. | ||
1980-later models needed the heads to be machined for reverting to the straight up o-ring seals. |
Bendix
Keihin Butterfly
These V-twin clamps (35-0419) work well for stopping intake leaks. The tool to install them is the same as any oiteker clamp pliers. 13)
14) 15)
4)
1979-1985 HD Sportster Parts Catalog
5)
photos courtesy of Ebay seller, animalhouse2010, Link to Ebay store:
6)
photos courtesy of Ebay seller, Robison Motorcycles Link to Ebay Store
7)
See Brucstoudt & Dr_Dick - XLForum - http://xlforum.net/forums/showthread.php?t=2079889
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photo by The Doctor71 of the XLFORUM http://xlforum.net/forums/showthread.php?t=2071371
13)
66xlch of the XLFORUM http://xlforum.net/forums/showthread.php?t=1079081&page=5
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photo by 66xlch of the XLFORUM http://xlforum.net/forums/showthread.php?t=1079081&page=5
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photo by DirtyCory of the XLFORUM http://xlforum.net/forums/showthread.php?t=1079081&page=7