Author Topic: V7 Sport v T3/Lemans Tacho Question  (Read 335 times)

Offline 1down5up

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V7 Sport v T3/Lemans Tacho Question
« on: November 29, 2021, 10:19:34 PM »
All - A question for the train spotters out there.

I am looking to put a set of v7 sport instruments on a Lemans project I am working on (bike was a basket case MK2, putting it back together as a 750s/v7 sport style)

The Veglia Tacho (black face) on a v7 sport Red Lines at ~7,000rpm and finishes out at ~8,000rpm

However on the Veglia T3/Lemans (Blue Face) the Tacho Redlines at ~8,000rpm and finishes at ~10,00rpm (in roughly the same arc/spot that it his 8,000rpm on the V7 Sport )

My Question for those that have made it this far, does anyone know if its just a difference in the internal gearing of the Tacho, or is it a different Pinion/Drive gear at the tach drive.

The Part number for the drive gear (the one with the 2 steel washers in the timing cover) is the same acros the big blocks (14 76 92 00), so it would just be a different drive gear on the camshaft (unlikly?) or different gear in the tacho....

For whats its worth the speedo is the same (160mph/240kph)



Offline guzzista

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Re: V7 Sport v T3/Lemans Tacho Question
« Reply #1 on: November 30, 2021, 04:36:13 AM »
methinks it's just plug and play for you and in the end you will have the same "Vague-lia" tach reading , just different graphics. Red line begins at approx 7500 on V7S and at 8000 on LM. Never had a V7S or Loop tach apart, but wouldn't be surprised if internals were cheapened on the blue faced deTomaso era Veglias
« Last Edit: November 30, 2021, 04:39:01 AM by guzzista »
1975 750S Tribute bike, 1994 Cali 1100, 2007 Ducati GT1000, 1983 SP1000 1967 Vespa 180 SS, 1976 Vespa Rally 200

Offline 1down5up

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Re: V7 Sport v T3/Lemans Tacho Question
« Reply #2 on: November 30, 2021, 01:11:10 PM »
Yeah, thinking more on it he logical answer is its just a slightly different internal gear ratio between the two tachos.

Online Antietam Classic Cycle

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Re: V7 Sport v T3/Lemans Tacho Question
« Reply #3 on: November 30, 2021, 01:36:47 PM »
Either tach works on either bike, so AFAIK there is no gearing difference in the tach or drive gears. Perhaps Guzzi was just being a little cautious with the V7 Sport redline, found it wasn't necessary and revised it for later models.

Loopframe Guzzi tachs are electronic.
Charlie

Wildgoose Chase Moto Guzzi

Re: V7 Sport v T3/Lemans Tacho Question
« Reply #3 on: November 30, 2021, 01:36:47 PM »

Offline 1down5up

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Re: V7 Sport v T3/Lemans Tacho Question
« Reply #4 on: November 30, 2021, 06:15:51 PM »
Cheers Charlie, i'm thinking it may even be as simple as a stiffer return stpring in the tacho pushing against the revs of the cable that allows a different redline/max rpm position relitive to the face


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