Wildguzzi.com
General Category => General Discussion => Topic started by: canuck750 on June 14, 2015, 11:37:37 AM
-
I got fed up trying to keep the 40+ year old tachometer working in my Eldorado, went through two in the past two years. The damn things start flapping wildly then they interfere with the spark and the plugs being to foul up and finally when the tach dies the ignition cuts out completely. I found new reproductions on-line from Spain and ordered one, it arrived quickly. "The Speedometer Store" is on Ebay and you can google it as well.
(http://i249.photobucket.com/albums/gg217/canuck750/1972%20Moto%20Guzzi%20850%20Eldorado/P8070001_zpst4uioile.jpg) (http://s249.photobucket.com/user/canuck750/media/1972%20Moto%20Guzzi%20850%20Eldorado/P8070001_zpst4uioile.jpg.html)
(http://i249.photobucket.com/albums/gg217/canuck750/1972%20Moto%20Guzzi%20850%20Eldorado/P8070002_zpshudblsri.jpg) (http://s249.photobucket.com/user/canuck750/media/1972%20Moto%20Guzzi%20850%20Eldorado/P8070002_zpshudblsri.jpg.html)
$212.00 US + shipping, they have lots of other instruments for sale for many bikes
http://www.ebay.com/itm/161687473102?_trksid=p2060353.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT
The repro does not have "Electronic" stamped on the face and the Red Line is set at the higher V7 Sport limit, I think they make one face that they use in both the electronic and the mechanical tachs for the whole line of replacement Veglia instruments.
(http://i249.photobucket.com/albums/gg217/canuck750/1972%20Moto%20Guzzi%20850%20Eldorado/DSC02708_zps289e8c8a.jpg) (http://s249.photobucket.com/user/canuck750/media/1972%20Moto%20Guzzi%20850%20Eldorado/DSC02708_zps289e8c8a.jpg.html)
I will post how it works once I get the thing installed.
-
Thanks Jim - mine is completely erratic, but I hadn't realised it had implications for the other workings on the bike. I'll keep an eye open for troubles.
Nick
-
Great find!
-
Jim,
I reckon if you approached Speedhut they could fit one of their works into your existing case using the original dial.
Their units are only 1" deep.
The folks at Speedhut are amazing to deal with.
-
I installed the new reproduction tachometer in my Eldorado today, along with a Harper's Electronic ignition kit (thanks Charlie). The good news is the tachometer is steady, no wavering or sweeping back and forth (and the bike started up right away and ran pretty good on a 2 hour run, no issues).
The bad news - I think it is reading half the actual rpm. The bike is idling at 400 ~ 500 rpm and cruises along at 40 miles an hour around town at just under 2000 rpm.
I connected the + (blue) wire from the coil + sides to the + terminal on the back of the tach and the black - wire to the negative terminal on the back of the tach and the negative terminal on the coil. The small centre of terminal on the back of the tach is equal to the original and the two small wires connect to the centre terminal.
Could I have something incorrect in the connections or is this a case of you takes your chances and you get what you get?
-
I don't see how a floppy tach, I had one on my 72 Eldo could have any affect plugs fouling or other ignition issues, unless the ignition is on the same wiring loop as the tach and the ignition died and you saw the tach die, but the tach cannot kill the Eldo in my experience, and I have had plumes of smoke coming out of my Eldo and it still ran :grin:
-
The tach probably expects 1 pulse per revolution (one coil with distributor). with the electronic ignition do you have it on just one cylinder?
If that's the case I would try joining the two signals together with a couple of resistors, say 1K Ohm.
Send me the schematic for the ignition I will try to figure it out.
-
I don't see how a floppy tach, I had one on my 72 Eldo could have any affect plugs fouling or other ignition issues, unless the ignition is on the same wiring loop as the tach and the ignition died and you saw the tach die, but the tach cannot kill the Eldo in my experience, and I have had plumes of smoke coming out of my Eldo and it still ran :grin:
I've been riding with Eldo riders twice now when the bike stops running, no spark, gap is fine, power to coil, etc. Tach is disconnected and spark is "miraculously" restored. When the tach dies, it sometimes grounds the points, killing spark.
-
Well, there you go, you know this stuff very well.
-
if there was a waste spark on the electronic ignition, the tach would read high, not low. if the tach is made for the v-7 sport, it is expecting a dual point/dual coil ignition. while one wouldn't think it should matter, that plus the electronic ignition (is this the one that harpers sells that still uses the cap and rotor and one coil?) could do you in.
-
Jim,
I reckon if you approached Speedhut they could fit one of their works into your existing case using the original dial.
Their units are only 1" deep.
The folks at Speedhut are amazing to deal with.
Speedhut (I don't like their name) is a good instrument maker based in the USA. I have one of their units on a BMW single. Finding an electronic tach for a single is difficult.
Speedhut is great. I had to call the factory about programming the tach and I was put through to the engineer who fixed me up.
http://www.speedhut.com/gauges/
So far, the tach has worked perfectly. They look great too and have many optional faces etc.
I would expect that they could possibly convert an old tach for somebody. If not, Hartmut at Palo Alto Speedometer, could possibly perform the conversion using new guts in an old can.
-
if there was a waste spark on the electronic ignition, the tach would read high, not low. if the tach is made for the v-7 sport, it is expecting a dual point/dual coil ignition. while one wouldn't think it should matter, that plus the electronic ignition (is this the one that harpers sells that still uses the cap and rotor and one coil?) could do you in.
V7 Sport tach is cable driven, so the repro tach can't be made for that.
-
V7 Sport tach is cable driven, so the repro tach can't be made for that.
good point, but it could be "aftermarket" made for it, even if stock they were not electronic. my point is it had the v-7 sport redline, and dial face wording, why not internals which expected a dual point dizzy?
-
The same company distributes a cable driven tack for the V7 Sport using the same face (the tach face is actually correct for the V7 Sport not the Eldo).