Ridemalibu Motorcycle Rentals & Tours – Los Angeles CA
  1. Ciao Guest - You’ve landed at the ultimate Guzzi site. In SoCal? See the SERVICE tab above for the best in service, tires, tuning and installation of our products or custom work. NEW FORUM REGISTRATIONS REQUIRE EMAIL ACTIVATION - CHECK YOUR SPAM FOLDER. ALWAYS TRY A SEARCH BEFORE STARTING A NEW TOPIC - Most questions you may have are already answered on the Forum with FACTS, NOT OPINIONS. PLEASE DON'T BE A DRIVE-BY POSTER: As a common courtesy, check back if you are posting elsewhere on the web. Note there's decades of Guzzi hands-on experienced help on this site, all whom give endless amounts of their time for free; BE COURTEOUS AND RESPECTFUL! There is zero tolerance on personal attacks and off-site links to other Forums or competing products. Also be sure to click on the STORE link also above for our 600+ product inventory, including many of our 100% Made-in-house-USA GTM products and engine kits. We appreciate the consideration, understanding and your business... past and future. And if you haven't seen our MotoCycle (not) art, click on the BUILDS tab above to see our work at our sister business; GT MotoCycles®-- WE ARE ONLINE ONLY - NO PHONE CALLS MADE OR RECEIVED.

VDO speedometer & Acewell speed sensor

Discussion in 'Loop & Tonti' started by edgrew, Mar 8, 2012.

  1. edgrew

    edgrew Just got it firing!

    Joined:
    Mar 8, 2012
    Messages:
    2
    Likes Received:
    0
    Hello,
    I have just completed the fitting of an 80 mm VDO speedometer and Acewell speed sensor unit (ACE-S4) to my circa 2005 Cali EV. I bought the VDO over the Auto Meter speedo because it seemed to look more watertight for our UK weather. Time and water will tell :lol:
    Previous postings mentioned that there were problems with the Acewell linking up to the VDO.
    I contacted a very helpful gentleman (John) at http://www.etbinstruments.com/ in the UK and sent him an Acewell to go with a VDO speedo. ETB sell VDO, but not Acewell parts. He got the pair to link up and sent me the following wiring diagram:-



    The 1K ohm resistor is the trick.

    John at ETB asked for speedo cable revs per rear wheel revolution. The VDO requires pulses per mile input. We worked out that with a 150/70 x 17 rear tyre and 2.7 revs on the speedo cable end per rear wheel rev you get 2110 pulses per mile. When you calibrate the speedo the input is 211 on the "pulse" function (ignore the "1"s column and miss off the "0"). This presumes that the Acewell gives one pulse per rev. It is easy to calibrate statically.



    As mentioned previously,the VDO fits straight in to the EV instrument housing. However there are a few modifications required. The chromed speedo cover originally had the mounting holes placed horizontally on the ITI speedo. The VDO mounting bolts are at an angle so I had to enlarge the slot for the wiring (where it emerges from the warning light pod) at least x 2 with a Dremel hand tool to get the holes to line up. (The hole centres are the same on both speedos by the way). Although the chrome cover is twisted through an angle I still think it looks OK. I put some black silicon (I had some handy) in the old odometer reset spindle grommet and refitted.



    I started the bike up in the garage on the centre stand and engaged the gears. The speedo worked fine :D To double check the calibration I engaged a suitable gear and ran at 30 mph for 1 minute. The odometer clocked up 0.5 miles. If my maths is correct this sounds OK. I ran the bike on the road for approx 10 miles.
    I haven't glued the chrome bezel on yet because I want to test the unit for a few hundred miles just in case there is a problem. I picked the MPH and KPH speedo faced model.



    The only other hiccup I discovered was that the knurled "cable" end nut on the Acewell unit was longer than the original mechanical Guzzi cable one. The Acewell unit wouldn't tighten up enough. I fitted a small brass washer inside the nut to sort this out. You might have to look at this carefully because a standard metric washer might interfere with the spinning drive cable. I also found some small fibre washers to be of the correct size / hole diameter that would do the trick.

    The beauty of the Acewell is that it fits straight on (remembering the knurled nut) without any modifications to air boxes etc. Obviously you have to fit your preferred wiring connections along the way.

    It is early days yet for this set up and I will post an update. My original ITI speedo odometer stopped working at 7400 miles. The Moto Guzzi GB website has a post describing how one might repair the internal gears of the odometer by cutting open the plastic casing and having a go. On doing this I discovered that the quality and fit of parts within the ITI speedo are very poor. In the UK a replacement ITI is circa £190 and will probably suffer the same fate at a similar mileage. The VDO set up cost about the same in the UK. To me there is no contest :)

    Many thanks to previous correspondents for the idea of using an electronic solution.

    John.

    P.S. On removing the chromed rev counter plastic cover I found that it had been half full of water that was trapped in there. ( I did mention our British weather :cry: ) I ground a small water drain hole with the Dremel to sort this out I hope.
     

    Attached Files:

  2. john zibell

    john zibell Moderator Staff Member GT di Razza Pura

    Joined:
    Oct 28, 2008
    Messages:
    8,019
    Likes Received:
    856
    Location:
    Huntsville, AL
    Excellent post, it is so good I made it a "Sticky" for future reference.

    Thanks,
     
  3. GT-Rx®

    GT-Rx® Administrator Staff Member GT di Razza Pura

    Joined:
    Jul 1, 2009
    Messages:
    11,413
    Likes Received:
    3,493
    Location:
    Malibu
    Thanks John(s), excellent post/great info! I revised the photos above.

    I also added everything to the Tech tab above under CSL&F section (direct link HERE)
     
  4. iconicmug

    iconicmug Just got it firing!

    Joined:
    Feb 14, 2012
    Messages:
    2
    Likes Received:
    0
    Location:
    Burton on Trent
    As promised, here is an update to the VDO / Acewell speedo set up on my California EV.
    The original post was sent in by my brother because I was having trouble including images and he knows more about computers than me.
    I have now done over 500 (dry weather) miles so far. The speedo is working fine apart from a small glitch. The needle gave a "kick" of approx. 8 MPH over the current road speed at certain times. This was abitrary e.g. it might be after 1 mile or after 3 miles and at random road speeds. At all other times the needle was steady and on acceleration there was a linear increase in indicated speed. The needle can be a bit "clunky" when decelerating quickly from below 20 MPH because of the relatively low input pulse speed from the Acewell unit. This is no problem to me, nor is the "kick", but I contacted John at ETB instruments to see if anything could be done to improve this "kick".
    John suggested different "pull-down" resistor values. He said try 2K ohm and 750 ohm i.e. either side of the original 1K ohm.
    I set up a variable resistor as a temporary measure and started the bike up on the centre stand. At 2K Ohm it was obviously the wrong way to go and the needle "kicked" every few seconds. I then tried 750 Ohm and the needle remained steady for a couple of minutes at various speeds.
    The only resistor I had to hand was a 800 ohm and I soldered this in situ.
    Ran the bike for 20 miles and most of the time the needle is perfect. Very occasionally it will give a slight small "kick".
    I contacted John and asked what he considered to be the minimum value resistor. He suggested 500 ohms, but advised not to go any lower. He mentioned that a very low resistor would not harm the speedo, but he didn't know what was in the Acewell sender and thought that this may come to harm at low resistance levels.
    I have decided to leave things as they are for now with the 800 ohm. The slight occasional "kick" is not a problem and the rest of the set up is so neat.
    The clock face is nicely lit up at night by the way.
    I might send another update when (hopefully) I have done many more miles.
    John.
     
  5. Seekhunt

    Seekhunt Just got it firing!

    Joined:
    Jan 7, 2009
    Messages:
    8
    Likes Received:
    0
    Location:
    Courtenay, B.C.
    This looks good, but I need to ask why not a mechanical speedometer? Autometer Designer series 1476 fits the 3 1/8 (80mm) requirement. My bike suffers the same malady, and I'm about to replace the ITI. Can someone enlighten me?
     
  6. MLTGuzzi

    MLTGuzzi Just got it firing!

    Joined:
    Jul 22, 2013
    Messages:
    7
    Likes Received:
    0
    Location:
    Waxhaw
    I have a 2000 Jackal. The factory speedometer stopped working at about 38,500 miles. I have purchased a VDO speedometer (437-750 I believe). It's the one that looks like a 1930's gauge. I also bought the Acewell ACE-S4, which installed on the back of the transmission without a hitch.

    I have it all wired up, and I have lights, the test cycle, everything working as expected, except it won't calibrate. It's as though the signal is not getting from the sensor to the gauge. I wired it as best I could, based on the VDO instructions and your diagram. At first I had the white wire from the sensor going to pin 8 on the gauge. That didn't work, so I switched pins 7 and 8, and moved the resistors accordingly. Still nothing. I'm using two 1k ohm resistors in parallel, which should yield 500 ohms.

    Any ideas would be appreciated.

    Thanks,

    Marty
     
  7. iconicmug

    iconicmug Just got it firing!

    Joined:
    Feb 14, 2012
    Messages:
    2
    Likes Received:
    0
    Location:
    Burton on Trent
    Hi MLTGuzzi, I hope that this email reaches you. I tried to send an email before, but this may have gone astray.
    My computer crashed a couple of days ago, so I'm not used to this borrowed computer. I have also just read your post on the forum.
    You are using a slightly different speedometer head I believe. One would hope that the electronics are the same. You ask about the live feed to the Acewell. I can't just remember now where I tapped into without removing the "gas" tank, but this needs its own switched (fused also) 12 volt + (positive) supply. You could try a direct fused temporary supply from the + side of the battery to prove that the Acewell is working or not. Also take note of my comments in the original post about the Acewell unit needing a bit of tweaking on the knurled nut plus appropriate washer. You could try removing the Acewell and spinning by hand / slow drill to prove that it is turning and power up the speedometer at the same time.
    I originally connected everything up temporarily with "chock blocks" to prove that it worked. Good luck!

    An update on the performance after approx. 5000 miles. The unit has proved to be water tight despite our British weather! Only once or twice has the inner glass surface misted very slightly when moving the bike from warm garage to cold outdoors or vice versa. This clears within minutes.
    I have discovered that the single "kick" on the needle as mentioned before coincides with using the indicator.
    I presume that the slight voltage drop might influence the speedometer and "trick" it into thinking there is another brief signal from the Acewell! I am no expert, but would voltage stabilization help? Interestingly, my 1988 Harris Matchless with Rotax engine does exactly the same "kick" on the rev counter when I use the I indicators!
    I am very pleased with the system. The speedometer is dead accurate after calibration at all speeds compared to Satnav info. It was very easy to calibrate. I hope that this is of some help. Please feel free to contact again.
     
  8. MLTGuzzi

    MLTGuzzi Just got it firing!

    Joined:
    Jul 22, 2013
    Messages:
    7
    Likes Received:
    0
    Location:
    Waxhaw
    Thanks Iconicmug,

    I'm trying to put together a complete schematic, showing how to use the Acewell S-4 with a VDO speedometer. I spoke with someone in tech support who says they are all the same, except for size, trim, and face. I'm going to attach a schematic here, showing my next attempt. I'm not sure if pin 2 provides the +12v to the sensor, or if I must jump pin 8 to pin 6. Some experimentation is in order. It would be a big help if you could look at the schematic and see if this looks like what you did.

    When I have it working, I'll post the entire wiring schematic here.

    Thanks,

    Marty
     
  9. MLTGuzzi

    MLTGuzzi Just got it firing!

    Joined:
    Jul 22, 2013
    Messages:
    7
    Likes Received:
    0
    Location:
    Waxhaw
    Just a quick update. Late last night I put a meter on pin 2 and found that it does have power. I wired everything as shown in the schematic (without the jump from pin 8 to pin 6). This time I did get pulses from the Acewell, but the needle jumps all over the place after calibration. It seems that revving the engine makes it think we're going faster. I have two more things to try. The first is to jump pin 8 to pin 6, as shown in the VDO documentation for a three wire sensor. The second idea is that I'm getting signal interference because I bundled the +12v and ground in a wire loom with the sensor wires. More later.

    Marty
     
  10. MLTGuzzi

    MLTGuzzi Just got it firing!

    Joined:
    Jul 22, 2013
    Messages:
    7
    Likes Received:
    0
    Location:
    Waxhaw
    Time for another update. Operationally nothing has changed since my last update. It will now calibrate, but in operation the needle jumps all over. I have tried the following;

    1.) Connected Pins 6 and 8 to the white wire from the Acewell S-4.

    2.) Connected the +12v directly to pin 4 and the red wire from the Acewell S-4. I thought maybe the power from pin 2 was not a reliable +12v.

    3.) Removed the wire loom and separated the wires as much as possible, to avoid possible inductance from the +12v or ground into the signal wire.

    Additionally, I observed that the speedometer seems to react to engine RPM. Even at a full stop, if I rev the engine the speedometer will jump around, as far as 60 mph at times. While moving, if I pull in the clutch and close the throttle the speedometer will drop down around 5-10 mph when I'm moving much faster than that.

    I noticed that the speedometer reports around 13,700 pulses over a measured mile, which seems much too high when compared to numbers reported elsewhere in this forum. This further reinforces my assumption that the speedometer is interpreting some type of interference as a legitimate pulse on the white wire.

    As I'm writing this it occurs to me that I need to check the routing of the Acewell wire to see if I placed it too close to a coil or spark plug wire. Will report back after I get a chanced to try it.

    Marty
     
  11. MLTGuzzi

    MLTGuzzi Just got it firing!

    Joined:
    Jul 22, 2013
    Messages:
    7
    Likes Received:
    0
    Location:
    Waxhaw
    And yet another update. I had attached the ground wire where the ignition unit is grounded. When I moved the ground to a different bolt, the symptoms changed.

    1.) Upon calibration over a measured mile, the counter showed something near 4300 pulses, rather than 13,000.
    2.) The speedometer doesn't jump all around now, most of the time, but it also doesn't show an accurate speed. It reads slow.
    3.) Occasionally, the needle will jump up to 40 or 50 mph and then back. It does this sometimes when sitting still.
    4.) When I rev the engine, sitting still, the odometer begins to flash. It will do this several times and then stop.

    Next steps;
    1.) Run a dedicated ground wire back to the battery.
    2.) Run some more tests with different resistance values.
    3.) Maybe pull the +12v directly from the battery to see if the problem remains.

    I still think I'm getting interference over either the +12v or ground wire.

    Marty
     
  12. MLTGuzzi

    MLTGuzzi Just got it firing!

    Joined:
    Jul 22, 2013
    Messages:
    7
    Likes Received:
    0
    Location:
    Waxhaw
    Reporting in again. It's been a few days since I've had time to work on the Jackal/VDO/Acewell problem. Yesterday I pulled the tank off again, and sure enough, the +12v wire had dropped down and was at just about 90 degrees to one of the spark plug wires. I pulled it back up and wire tied it away from the coil and plug wires. Now the pulse count is down around 2700 over a measured mile. I've calibrated it, but I hit traffic right about the time I came to a measured mile. I didn't hit the button right on time, so it is now showing about 3 mph slow. I'll try again today or tomorrow.

    I'm still having some issues when I'm stopped, or almost stopped. The needle sometimes jumps around like it can't figure out how fast I'm going. This may be related to the resistance between pin 8 and ground.

    More later,

    Marty
     
  13. kathie

    kathie Just got it firing!

    Joined:
    Jul 12, 2017
    Messages:
    1
    Likes Received:
    0
    Location:
    canada
    my speedo wasn't working, so I replace the speedo VDO speedo and

    VDO SENDER / ADAPTER FOR ALL VDO- ELECTRONIC SPEEDO'S - INCLUDES SPEEDO CABLE (ALL MODELS OF AIR-COOLED VW). Cable spins, but I have no reading on the speedo. Any ideas
     

Share This Page