Installing an Acewell speedo/computer on an airhead --

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

  1. Boxer_Bolshie

    Boxer_Bolshie n00b

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    I am wiring the speedo and have some wires unaccounted for. Anyone want to give it a shot and tell me to what these wires connect to? And should I connect all of the BMW brown ground wires to the one black Acewell wire?

    NOTE: The blue Acewell wire noted as fuel gauge will not be used

    [​IMG]

    Here is what is supposed to be my wire diagram (my actual wiring seems a little different)

    [​IMG]

    Here is the Acewell speedo diagram I got from bpeckm's earlier posting

    [​IMG]

    Here is another colour code for the Acewell harness to BMW harness

    [​IMG]
  2. Boxer_Bolshie

    Boxer_Bolshie n00b

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    So this is what I've figured out so far on the extra wires.

    The BMW blue and one of the browns go to the generator charge light
    The two BMW black and white striped wires go to something called a scale light (maybe dimmer light/switch?)
    The BMW blue and green striped wire with one of the brown wires go to something called a speed warning light.

    I am headed to NAPA to pickup a light for the gen charge but the last two I have no idea what to do with. Anyone want to fill me in?
  3. craydds

    craydds Long timer

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  4. craydds

    craydds Long timer

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    My bike is a '75 R90S. I have not started my installation, but have studied bpeckm's wiring instructions, Acewell instructions, R90S wiring schematics, and my stock instrument cluster and wiring harness; I think I have it planned out and it looks like the connections will be straight forward. It appears like your R65 has a significantly different wiring harness compared to my R90S. Hopefully some inmates familiar with R65's will chime in. I will make pictures during my installation, maybe that could help you somewhat. Hope to get started next week.
  5. bill42

    bill42 Old-School BMWs

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    I for one will appreciate those pictures! I will be starting my ace well install soon on my R100 and your R90s is probably pretty similar. I have decided that I don't like the 2 wire clusters that enter the top of the headlight shell. They are hidden with the stock dual gauges but with the Acewell they are very noticeable. I think I am going to route those to the bottom of the headlight as I do the ace well install. Then cap the top holes with plugs or something.





  6. craydds

    craydds Long timer

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    I have the wiring diagrams from Prospero's. They are a help in understanding your electrics but I don't think they are precisely accurate; I have found the actual wiring on my bikes differ from Prospero's diagrams. I rely on the schematic in my owner's manual. It is microscopic print so I made a 150% enlarged copy which now I can read. Perhaps you, too, might refer to a R65 owner's manual for an accurate schematic.
  7. Brun

    Brun Been here awhile

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    For those pondering how to fit the speedo sender to a slash 6 I offer the following as a possibility -

    [​IMG]

    It's just a piece of 1mm stainless folded using a vise, wood blocks and a hammer, and drilled to suit. I used the magnetic bolt that came with the Acewell kit to replace one of the bolts in the hub - it is the perfect size (the one at 12 o'clock in the photo). The nice thing is that the sender comes off with the axle nut and is therefore out of harm's way when fooling with the wheel.

    Routing the cable is another matter. For the moment it is zip tied onto the fork leg with a loose section running behind the gaiter. Probably best to run it up the brake line. Or maybe it can go through the gaiter somehow. I'll ponder that.

    My headlight and instruments were trashed in a nasty incident with a cow, so I was looking for alternatives. I bought a chinese copy of a russian copy of a /5 headlight on ebay. It has a hole of 85mm diameter, and the Acewell is somewhat smaller (67?). I lathed up a donut of 6mm polycarbonate (90mm OD) with a rebate around the lower outside edge to suit the hole. This got a squirt of rattlecan black and it kinda looks like it's always been there.

    [​IMG]

    I used a 3W normal bulb for the alternator light. The hole for this was already in the bucket. I like the Acewell a lot. I calibrated it using a GPS taped to the handlebar, adjusting the numbers until I got it right. I have fun holding the speed at 109.9 while going past police radar traps on the freeway.

    My only issue with the instrument is that the LEDs are nowhere near bright enough during the day. I'm planning to bypass them and fit an arc of idiot lights over the top of the unit. As you can see, I'm not fussed at all about keeping things stock on my R90 slash 5.9.
  8. craydds

    craydds Long timer

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    Nice job! My unit has been shipped from Acewell UK and should arrive soon. Hopefully I'll have some pictures to post next week.
  9. Padmei

    Padmei enamoured

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    Good work.
    Was that headlite on ebay.au?
  10. Brun

    Brun Been here awhile

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    Sorry mate, not sure. A friend bought it and didn't bond with it, so sold it to me. It was a couple of years ago. It is not very well made - not even symmetrical - but neither am I so it suits me just fine.
  11. Super rider

    Super rider Adventurer

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    Ever since I installed my Acewell on my 75/6 the top main fuse in the headlight keeps blowing. I've replaced it three times
    Now. Never happened before. I installed it per the diagram and everything appears right. Anyone else have this problem? Can I just get a higher amp fuse? Thinking maybe it's drawing too much power for some reason. Any thoughts?
  12. bpeckm

    bpeckm Grin!

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    Not likely that the Acewell would draw any significant amount of power... it sounds like you have something else going on.... a bigger fuse might help, but if it keeps blowing the same amperage fuse now, it's not likely that a bigger fuse would help.

    I think I would be looking for a pinched wire somewhere, or a chafed wire maybe...

    Good luck, those kind of problems are a real pita.....

    :D
  13. Super rider

    Super rider Adventurer

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    Yeah that's what I'm worried about. It's definitely a result of installing the Acewell, either the unit itself or a wiring problem I caused when I did it. Never blew a fuse for years now everytime I ride it the thing blows. Not looking forward to tracing all that crap back ;(
  14. Jeremiah

    Jeremiah Been here awhile

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    I am getting ready to order an Acewell for my R65 - did you get yours working? And did you ise the magnetic pickup or the cable?
    Inquiring minds need to know - I don't have any hair left to pull.

    Thanks
    Roy
  15. Hedge36

    Hedge36 My e-penis is huge.

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    I used the gearbox sending unit. Not surprisingly, my wiring didn't match any diagram I could find, so I spent an hour with the multimeter playing process of elimination - had a couple of spare wires from the original instrument plug that I never did figure out.

    Little chrome bezel charge light poked through the headlight bucket, works a treat.

    Still need to calibrate the speedo setting - does anybody know if there's any needed conversion when using the gearbox sender, or is straight circumfrence sufficient?

    Now I'm eyeballing the stock instrument bracket as a base, because I'm not thrilled with having the unit clamped to the handlebar.

    I understand, also, that you have 1,000km to set the base odo setting before it locks in - anybody have info on how to set that? The documentation is pretty sparse.
  16. craydds

    craydds Long timer

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    Search this thread; speedo calibration is addressed in several posts.
  17. Hedge36

    Hedge36 My e-penis is huge.

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    Um, yeah, thanks. You'll note that no one ever came up with an actual <i>answer</i> to the question of calibration when using the boxer gearbox adapter.
  18. craydds

    craydds Long timer

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    The actual answer for YOUR bike is the exact "circumference" for YOUR bike. Here is one way to measure it:
    1) Attach the speedo cable into the tranny, speedo end unattached. At the speedo end, place a "flag" on the cable using a wire/paper clip/bobby pin/etc. The "flag" will be used to mark one 360 degree rotation.
    2) Get the bike ready to roll forward. Mark a "start" pencil line on floor directly beneath the rear axle (use a framing square, plumb bob, etc.)
    3) Roll the bike forward for one full rotation (360 degrees) of the "flag" on the speedo cable, and stop.
    4) Mark a "stop" line on the floor beneath the rear axle. Measure the distance between the start and stop lines in millimeters. This is your "circumference".
    5) Enter the circumference into your Acewell. Go out and test ride with a GPS onboard. If your Acewell does not agree with the GPS, adjust the circumference entry accordingly. Re-test.
    Best of luck to you.
  19. Prutser

    Prutser Long timer

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    I am using the Motogadget's with the gearbox speedo sensor intended for the acewell .
    If you would drill a hole in the alloy bush thats around the sensor.
    And sink in the motogadged reed sensor. You wil see your speedo will work on the magnet thats in the rotor.
    [​IMG]

    Using it on 3 bikes and works perfect.
  20. Airhead Wrangler

    Airhead Wrangler Adios Mexico

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    Got much experience with the motogadget speedo? I was considering one of those to replace my banged up vapor computer.