Eldo / Ambo GPS Speedometer

[Canuck750]

I got tired of the hit and miss functions of the Veglia tachometer and speed on my Eldorado, been through two original tachometers and one Spanish reproduction tach and a couple original speedometers. Tachometers  just go kaput and the speedometer swings back and forth with a mind of its own.
I was lucky to get an Ambassador single instrument bezel from the Mayor of BBQ (thanks!) and have decided to ditch the tach and get a single new replacement gauge.
I looked into Speedhut gauges, but after shipping a combined speedo (gps) and electronic tach, delivered was over $700 USD

On eBay I found a GPS speedo (no tach) with a signal and high beam lights for cheap, but it is 3 5/8" diameter rather than  the 4" that the bezel takes

Under $100 USD with shipping

https://www.ebay.com/itm/114991059514



I made up a an adapter ring out of aluminum to drop into the Ambo bezel and take the smaller instrument, two 4 mm x .75 set screws through the sides of the ring snug it up to the dash piece









The wiring is very simple, power from key switch, ground, L and R signal, high beam and running light

the GPS antenna has about 8 feet of chord, I spooled it up and tucked it under the dash, secured with zip ties and then used 3M two sided mounting tape to secure the antenna to the vertical face of the master cylinder on my bike, anywhere with a line of sight to above will work



Once the key is on the GPS searches for a signal counting up from zero on the odometer until it reaches 300, at which time if no reception, it goes to error, and you have to switch off the ignition and start again. It took seconds to find the satellites once outside my shop and it works great!

The dash signal and high beam lights work fine but are a bit hard to see in sunlight. The background colour is orange / red.

I plan on fitting this speedo to a couple more of my vintage bikes, there is no fluctuation of the needle and by judging the traffic I was riding in for a couple hours of city and highway I think its accurate. After years of a crappy Veglia speedometer keeping me guessing as to the real speed I was travelling at this is a great replacement gauge for dirt cheap.

[Kiwi_Roy]

I have always been a fan of the Speedhut gauges.
I'm not sold on GPS however, the pulse input speedo is so easy to activate using a simple reed switch activated by a magnet spinning in the gearbox cable drive.

[jacksonracingcomau]

I have that same speedo on my uk bike, tonti not loop but irrelevant here.
You have described it’s problem well, on that bike, there is no kill switch (wired with starter switch on starter motor so “clean” right handlebar.
The delay “finding” itself is seriously annoying, not a problem from cold, while it warms up and I put hat and gloves on, I have time.
BUT filling up with petrol or at coffee/lunch/shopping stops, the delay is seriously inconvenient, so you don’t wait, sometimes it then does not find itself when moving so you turn off and on to restart the searching.
Same applies after tunnels, that does bother me in London or near Mandello, both are a regular occurrence.

Next year I’ll refit a kill/starter switch so I can leave main switch on for short stops so speedo stays live but ignition killed .
Or fit an Acewell (driven by reed switch on gearbox) as on my 3 others here in Oz. My favourite by far. GPS is accurate enough, no doubt, but digital drive far more so. For trip/odo give me Acewell, no lost miles due to searching.
I’ve also got accustomed to digital read out, analogue is no longer “natural” to me, it’s an annual reacquaint process like the linked brakes on that bike, They will be delinked next year.
Quite odd what old brains can deal with, swapping to right hand change reverse pattern on my loop is not an issue but speedo analogue/digital or linked/unlinked brakes change is colossal!

Acewell also has tacho bar over digital speedo, cheap too, loads of models various size round analogue to oblong digital, check em out

[Canuck750]

I didn’t have a problem today with the GPS finding satellites, after a gas stop it reconnected in seconds, same after a coffee stop. For the money, 1/7th the cost of a SpeedHut gauge, I think it’s worth trying it out. I would have preferred the SpeedHut but being a cheapskate (Guzzi content), I can’t justify another $600 for the addition of a tachometer in the gauge. If the GPS gauge fails I am only out $100 and can ‘upgrade’ to something better.
As for GPS, on my BMW K bike, I tend to watch the speed readout on the GPS rather than follow the digital speedo on the dash and the difference between the bikes speedo and the GPS (Garmin) is about 4% higher on the bikes speedometer read out.