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Installing SpeedHut gauges


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The Speedhut gauges are a good replacement for the troublesome Veglias, about $300 for a pair


A word of caution, they make many different types, you need 3-3/8" and be sure to let them know it's for a bike and they will add silicone to the glass. The reset button is normally through the glass but they have an option of adding a jack at the rear as you can see below. This jack is used to configure the tach for no of cylinders, calibrate the speedo and trip reset.

Avoid Canbus type, that's a communication bus for modern autos.

They also make GPS speedos but I prefer the old school pulse input

 I wanted a look somewhat similar to the OEM Veglia.



There was no room for the large nut that normally holds the gauge, in fact it's a tight fit in the back cover so I attached a central bolt that will also serve to keep the back secured. The anodized extrusion was laying around otherwise a short length of flat bar threaded to take a stud would do equally well. JB Weld is your friend.



The Speedhuts are only 1' deep so I sliced 3/4" out of the rear cover using a strip of masking tape as a guide.



 At the same time shaving off all the bumps and blocking off all the spare holes with bondo.



I had to reduce the depth of the lamp fitting in the process. This worked out well as I wanted to upgrade to LED lamps anyway.



The lamps are simply glued into the fitting with the wires soldered directly to the contacts, I expect the LEDs to outlast me. Note the original incandescent soldered in parallel with the low fuel light, this gives the fuel level sensor the current it needs to warm up when uncovered. Forceps are worth their weight in gold when soldering the wires.

I like to use the 194 miniature wedge base lamps from www.superbrightleds.com

They work on AC so polarity is not an issue.



A quick test. I know, I should have had them add the Guzzi logo.



I love the way the Speedhut numbers glow in the dark. You have a choice of 5 glow colours.



The speedo operates on any sort of a pulse, I quote

"The Speedometer is designed to work with any wave/pulse form from 1 volt - 100 volts. Pulses per mile from 500 - 250,000"

I made a simple sensor from a magnet and a reed switch, the case is made from aluminum sheet glued to the nut off an old cable. The switch is fastened to the

outside sensing the field through the aluminum. There are no wearing parts to worry about because the rotating magnet is supported by the gearbox shaft.

To calibrate press Start, drive two miles (4 km) then press End, Speedhut takes care of the rest. A runners GPS is perfect for measuring the distance. 



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this is very cool, thanks Roy! question about the tach: do you use the original wires from the harness that went into the veglia tach? or do you run a wire off the coils? if you do use the wires supplied by the harness, which one? other than the yellow power wire and the black ground, there are a couple of them (yellow and black stripe, red and black stripe), and the speedhut only has one input wire I think... would be much cleaner and easier to use one of the harness wires. looking at the wiring diagram it seems like the yellow/black wire runs to the ECU so I was going to try that one first.

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Yes, original yellow with a black stripe from the ECU, when you first initialize the tach you select how many pulses/rev to use.


 The red with black stripe comes from the headlight relay, if you use that to power the gauges they go through their startup routine every time you crank which is a bit annoying so I tapped into the wire direct from the ignition switch.

Edit- In hindsight I should have powered the electronics up from the yellow wire that was used to power up the Veglia gauge lights, it seems to be on with the key.


The tach has another small quirk, because it's a stepper motor it needs power to drive back to zero. When you turn off the key it stays up scale (the speedo would do the same if you turned off the key at speed. I know how to fix that but it's not annoying me.

If you stop with the kill switch it drives down 

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Cool, thanks Roy! How many pulses does the wire from the ECU put out, both? So, two pulses per rev? Or does it just send one?




(moderator edit/ 20 May 2017: the ECU rpm signal is two pulses per revolution. Very easy to select on the Speedhut tach. docc)

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I don't know the answer to that, it's over a year since I set mine up and I need re-training after a coffee break.

It will be pretty obvious if you have it wrong and dead easy to change.

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Question about the low fuel light trick: can a resistor be used instead? Something less fragile and longer lasting? I'm worried about that bulb burning out or breaking while being tucked away inside the gauge pod. I feel like some sort of solid state electronic component might be sturdier...

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You might be able to make a resistor work, but what value would you use?

It needs to be low enough to supply maximum Voltage to the thermistor but not so low it draws too much current when uncovered.

The lamp (bulb) on the other hand is low resistance when cold but high when the thermistor is uncovered and heats up.


The lamp should last a very long time because it's not subjected to thermal shock just a gentle change in Voltage up to about 10 Volts.



BTW on the earlier bikes if you accidentally swapped the petcock and sensor cables this puts 12 Volts directly on the sensor, it's ok while the tank is full but if uncovered the thermistor will become red hot in seconds and fuse, It doesn't set the fuel on fire because it's inside a metal jacket with just a very small slit to the tank. The connectors on later bikes are keyed to prevent this.

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  • 4 weeks later...

Hello Roy, I have the Speedhut gauges installed, and I am getting close to a first startup since my restoration project began last year. Everything seems to be ready to go but since the bike is not in a running state yet, I can't check the tachometer. I installed a resistor in the yellow/black line per the instructions when coming straight off the ECU...however, you didn't mention anything about that. Is that resistor needed only for automotive ECUs or something?

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Immediately after buying a 2004 Stone sidecar rig last year (with only 4970 miles on it!) the speedometer crapped out. Gears totally trashed. I could've bought another potential failure geared Veglia unit but chose instead to buy a SpeedHut GPS based speedometer. No cable, gears etc so if I change the gearing on the rig, there's no problem with recalibrating the speedo. About the only thing I would point out for the installation of this model of Speedhut is to take ALL of the extra antenna cable - and there is a lot - and bury it under the tank where it's well shielded from electronic interference. As an aside, don't check the output of the inverter inadvertently as it's several hundred volts. BTDT, bought the t-shirt. Whatever. :grin:


Also, although I didn't know it at the time, there are SpeedHut units better suited for motorcycle use by virtue of sealing and positioning of some case penetrations. You can as well, get a custom logo at the time of purchase and there are several very good files of various Moto Guzzi logos right here on v11lemans.com!

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  you didn't mention anything about that. Is that resistor needed only for automotive ECUs or something?

I don't have a resistor in mine, they may add it as a precaution where the pulses are direct from a coil and could be very high.

I suspect the pulse from the Guzzi ECU is a very nice 5 Volt square wave.

A resistor probably won't hurt though, the signal is just used to trigger the electronics in the Tacho. The Speedometer will accept any pulse from 1 - 100 Volts, I assume the Tach will be similar.

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  • 10 months later...

Thanks for this thread. The suggestion to use the yellow wire from a dash light for power was super-helpful. The ITI lights each have a pair of yellow (switched power) and black (ground) wires, so I used the two pairs from the speedo side to hook up:

  1. The supplied inline fuse (3 amp) to their multi-plug mini-harness (and ground) for switched power to the gauges 
  2. The supplied tiny inverter (and ground) to power the gauge lights (through their multi-plug mini-harness)

I'll be powering and lighting four gauges from these mini-harnesses.

  1. GPS Speedo (already powered up and locked a GPS signal)
  2. Tach (already powered up)
  3. Oil Pressure (not connected yet)
  4. Voltage (not connected yet)

The oil pressure gauge looks pretty straightforward and comes with a pressure sending unit. I needed to get a 1/8 NPT female to Metric 12x1.5 male adapter so it would fit where the stock oil pressure switch goes. The supplied sending unit is quite large, so I will probably get some 1/8 NPT threaded braided line and relocate it inconspicuously. 




Based on previous posts, I see that I should connect the green and yellow wire from the tach to the yellow (with black stripe) wire from the plug-in tach connector on the original harness. (You guys are making this easy for me). 


Some questions:

  1. Voltmeter - is there a wire in the dash that I can use? If yes, which one? and if no, where should I connect the feed for the voltmeter? (the Speedhut instructions just say "...volt source to be measured.")
  2. Leftovers - after I snip off the two remaining ITI gauge lights and stock tach plug (in hand in photo) is it best to just wrap the ends in tape - or should I join all three blacks and the two yellows from the lights? (I realize this is an Electronics 101 question - and that's about my level).

BTW - the wire nuts are just there temporarily. I'll solder and wrap it all properly once everything is connected and working.

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For anyone else thinking of these gauges, here is a photo of how I wired the power and lights to all four gauges. Speedhut's directions are pretty good and I have only a base knowledge of electronics. Per Roy's suggestion, I used the feeds to the light bulbs for the stock gauges. That's especially handy, because those lights are no longer needed anyway.


Power to the gauges is provided through the red, white, and black connectors (each gauge has a matching plug). I used one light bulb feed for that - but that one takes two power sources, the other (white wire) is supposed to join with the inverter at a dash light power source.


The inverter (little black box) powers the lights in the gauges via the two-wire black connectors (each gauge has a matching plug.) Just to keep myself straight, I used a second light bulb feed for that.


Each gauge has one more wire - for the signal it measures. I will put the GPS receiver under the plastic inner-fairing tray. Tach connection was described above. The oil pressure signal comes from a replacement sender (the placement of which I almost have figured out). I still don't know where to get the signal for the voltmeter, but I have a long wire.




To mount the volt and oil gauges, I made giant P-clamps from metal strap (the hardware-store stuff that comes in a roll) and split some vacuum line as a bushing for the inside. I was only trying to mock them up temporarily, but then I thought they looked pretty cool - I'll paint before final assembly.


BTW - gauges are not connected in this photo - but that's simple - just connect the matching plugs. I tested it - all four gauges light up and do the start-up needle-blip.

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Much appreciation for all of you who have shaken down this application. I am on Veglia speedo#3/tach#2, I feel certain this is in my Sport's future . . .


How large is the GPS receiver, and where could one tuck it in on a Sport?

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