Installing an Acewell speedo/computer on an airhead --

Discussion in 'Airheads' started by bpeckm, Nov 23, 2009.

  1. craydds

    craydds Long timer

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    Tete, I simply plugged the speed sensor plug "c" into the Acewell harness plug "C" as shown on the Ace schematic. Curiously, the Acewell schematic shows that the speed sensor WHITE connects to the Ace PURPLE, but on the actual wiring harness the speed sensor WHITE connected to BLACK which connects directly to ground (BMW brown). I thought I might have to connect white to the PURPLE but I tested it and it WORKS. I have not tried connecting white to purple because the speedo works, so I will leave it connected white to black. What does your schematic show? What does your wiring harness contain?
  2. tete

    tete clown shoes

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    Ok. I see. Yeah I plugged mine directly in, not splicing and grounding the wire. When I get back home ill splice the wire and ground it. See if that fixes it.

    I thought it was a simple plug and chug. Ill try your method and get back to you.
  3. benthic

    benthic glutton 4 punishment

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    Me too!

    I finally got a soldering gun this weekend and have been buttoning up all my connections - I hope to finish tonight...
  4. safa airhead

    safa airhead n00b

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    Just want to make sure i understand this correctly. You joined tacho wire onto the wire comming from points to coils. My rev fkcker like hell not stable and difficult to set up idle and timing.

    Just another quick question. Did you set up the tacho setting on gauge to 0.5 or 1?
  5. craydds

    craydds Long timer

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    Setting is 1.
  6. craydds

    craydds Long timer

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    I may have read that a resistor can be installed inline; I'll check into this later on today. Also, one can wrap the tacho wire around a spark plug wire.
  7. craydds

    craydds Long timer

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    Reviewed Acewell instructions. A 1M ohm resistor is included with the Ace. This can be installed in line (series) for the tach connection, may solve the problem. I have the analog tach which seems to operate correctly, but it also has a digital readout. I attached the yellow tach wire directly to the coil; I will go out and test the resistor and report back.
  8. craydds

    craydds Long timer

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    On my Ace, the tach digital readout is a bit erractic; the analog tach appears to give a steady reading. I tested the resistor inline but could not see a significant difference in the digital tach readout.
  9. tete

    tete clown shoes

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    I still have not done the white to ground but will do so this week some time
  10. benthic

    benthic glutton 4 punishment

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    [​IMG]

    I finally got to ride my bike this weekend:) and the Acewell worked damn near perfectly - i must have done the wiring correctly;)

    my speedo sensor is the one that plugs into the stock bmw speedo hole and required no adjustments - it reads perfect. not sure what problems tete was/is having - total plug and play.

    my tack seems to work at lower speeds, but i noticed that it bounces a bit at highway speeds. i wired the yellow acewell directly into the stock harness (black wire i think).

    I didn't find anything in the setup to let me turn off the fuel flashing. oh well.

    thanks for everyone's contributions to this thread! extremely helpful!
    Spencer
  11. craydds

    craydds Long timer

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    In the set-up menu, go to fuel sensor resistance settings - you could select the resistance, or select OFF mode.
  12. benthic

    benthic glutton 4 punishment

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    I don't think my 2853 has that option. I just looked at the pdf manual again and it makes no mention of it either. I'll check again when I'm home tonight...
  13. craydds

    craydds Long timer

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    My Acewell came with a temperature sending unit. I am using it for oil temp:
    [​IMG]

    It is the M10x1.0 thread:
    [​IMG]

    [​IMG]

    Sending unit seated in place:
    [​IMG]

    I used a crush washer and some gasket compound. No leaks so far:
    [​IMG]

    Still no leaks:
    [​IMG]

    On a water cooled bike one could use the sending unit for water temp, but for our old airheads why not use it for oil temp? It does function properly and I now have an oil temp reading on my Ace:
    [​IMG]
  14. some_guy

    some_guy Been here awhile

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    What model? I would have to figure out how to rig that up with the thermostat and oil cooler...
  15. craydds

    craydds Long timer

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    That is on my 1975 R90S. I previously had an oil-cooler/thermostat on it but it was removed and traded away. If you have the oil-cooler/thermostat you will have to find another location (methinks) for the sending unit. Perhaps tap into the oil pan? That was my original plan; seems simple enough. But I ended up doing it as pictured above.
  16. craydds

    craydds Long timer

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  17. batoutoflahonda

    batoutoflahonda Long timer

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    So I'm doing the Acewell and a Baja designs head light converted to an H4 high low, Eastern Beaver relay mod, and making a switch panel with an acc plug. I was wondering what you guys are doing with all those bulky connectors to make them look clean?

    The mess:

    [​IMG]

    [​IMG]

    I keep thinking aircraft canon plugs are the way to go. But it would mean repinning something like 80 wires.

    [​IMG]

    So, hit me with your ideas/solutions for a clean install.
  18. craydds

    craydds Long timer

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    :thumb
  19. batoutoflahonda

    batoutoflahonda Long timer

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    ^^^ nothing good comes easy, does it? :D
  20. craydds

    craydds Long timer

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    Sounds like a cool project that would have very neat and tidy results. Make lotsa pics!