SuzukiSavage.com - Technical specs for Mini Speedo

mpescatori

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Technical specs for Mini Speedo
08/25/10 at 07:44:48

Sorry for starting a new thread, but I couldn't find the original one.

I have a 2" tachometer fitted and will fit a new 4gal tank this coming winter.
This means no OEM speedo housed in the tank (hooray!) so I must buy a 2" speedo.

I have found a very nice 2" speedo with resettable tripmeter here
http://www.bikersoutfitter.com/item403510.ctlg

and I'm even willing to laugh at myself for a 140mph speedo n a bike that'll never ever be doing any m,ore than 70mph anyway...
BUT
what is the correct cable drive ratio ?
Huh

1:1 ?

2:1 ?

2240:60 ?

Could anybody pleeeze shed some light ?

...
...
...

I have also found a RonaldMcDonald speedo, it's a mere 60mph speedo, but hey, it's essentially all I need Cheesy

Any suggestions ?

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Maurizio Pescatori, Esq.
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Mikuni BST40, K&N filter, Stage2 cam, Verslagen tensioner, Sportster muff, 120 proof moonshine, Pirelli MT 66 tourers... and a chain conversion too !

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Charon Serious Thumper Offline Posts: 1811 Harvard, NE Gender:	Re: Technical specs for Mini Speedo Reply #1 - 08/25/10 at 15:24:28 Being as you live and ride in Italy, I'd think you would want one in Km/h.
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mpescatori

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Re: Technical specs for Mini Speedo
Reply #2 - 08/25/10 at 15:33:08

Hello Charon, look, as the song says, "I've been everywhere"

I can compute my speed in kmh, mph, fps, m/sec, knots and even weight and mach!

So, as long as I'm doing 35mph in a 50kmh area, I'm good.

As long as I'm doing 20m/sec in a 70kmh area, I'm OK.

When the bike is doing 30knots in a 35mph area, the going may be soggy but I'm legit.

Now, if I were to do a mere ton in a mach .5 area... now THAT would mean trouble !!!

Grin

Now... any help ? I'll be in the States as of late saturday evening and have some seriously scrumptious shopping to do ! Cool

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Maurizio Pescatori, Esq.
Gentleman Rider

Mikuni BST40, K&N filter, Stage2 cam, Verslagen tensioner, Sportster muff, 120 proof moonshine, Pirelli MT 66 tourers... and a chain conversion too !

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ralfyguy Serious Thumper Offline Posts: 932	Re: Technical specs for Mini Speedo Reply #3 - 08/25/10 at 16:03:37 The one in the picture says 60mph @ 2,000rpm. The S40 does 4,000rpm @ 60mph in 5th gear.
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Charon

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Re: Technical specs for Mini Speedo
Reply #4 - 08/25/10 at 17:07:52

I, too, can calculate speed in an assortment of units, even, if pressed, "furlongs per fortnight." It is just easier for me if the units on the signs agree with the units on the instrument.

I am pretty sure the speedometers which refer to 60 mph at 2000 rpm are referring not to engine rpm but to speedometer drive cable rpm. You might be able to use a calibrated variable speed drive to turn the S40/Savage speedometer at some convenient speed and calculate the ratio from that. An electric motor driven from the 50 Hz mains in Europe should turn about 1475 or 2950 rpm (nominal would be 1500 or 3000 rpm, but they "slip" a little). When I was in USAF we called it Precision Measurement Equipment Lab (PMEL). If you can sweet-talk some of those folks they can figure it out for you. I am sure NATO has an equivalent.

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mpescatori Serious Thumper Offline Romanum Thumperium Cavalco, yeaaah !!! Posts: 3547 Rome, Italy Gender:	Re: Technical specs for Mini Speedo Reply #5 - 08/26/10 at 00:15:47 "furlongs per fortnight." That was a good one !!! Yes, you're right, it probably... certainly means the speedo is meant to be wheel driven as opposed to gearbox driven. I'll have to think about it...
Back to top	Maurizio Pescatori, Esq. Gentleman Rider Mikuni BST40, K&N filter, Stage2 cam, Verslagen tensioner, Sportster muff, 120 proof moonshine, Pirelli MT 66 tourers... and a chain conversion too ! IP Logged

dinsdale Full Member Offline SuzukiSavage.com Rocks! Posts: 186 Ottawa, Canada Gender:	Re: Technical specs for Mini Speedo Reply #6 - 08/26/10 at 06:42:38 Have no idea on the ratios, hope someone does. Found this in the description though. Would be a good one for us up here , if it would work. Keep us informed! Quote: Available mph or kph
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mpescatori

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Re: Technical specs for Mini Speedo
Reply #7 - 08/26/10 at 08:15:05

dinsdale wrote on 08/26/10 at 06:42:38:

Have no idea on the ratios, hope someone does.

Found this in the description though. Would be a good one for us up here , if it would work. Keep us informed!
Quote:

Available mph or kph

Hello Dinsdale, yes, you have a point, but why bother (and waste my money) if I buy an item that'll show double (or half) the speed I'm actually doing ?

I mean, cruising at 90kmh (55mph) with a 240kmh (140mph) speedo is bad enough,
I couldn't bear having the needle lazily drag itself up to a whoppnig 25-30mph ...
...when I'm actually travelnig at twice the speed...

I have also found interesting electrical speedo calibrators for modified HDs, but our speedo is cable-driven... Undecided

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Maurizio Pescatori, Esq.
Gentleman Rider

Mikuni BST40, K&N filter, Stage2 cam, Verslagen tensioner, Sportster muff, 120 proof moonshine, Pirelli MT 66 tourers... and a chain conversion too !

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mpescatori Serious Thumper Offline Romanum Thumperium Cavalco, yeaaah !!! Posts: 3547 Rome, Italy Gender:	Re: Technical specs for Mini Speedo Reply #8 - 08/27/10 at 03:48:37 upping this thread because I need to know, should I buy a 2:1 or a 1:1 cable driven speed ? Please ?
Back to top	Maurizio Pescatori, Esq. Gentleman Rider Mikuni BST40, K&N filter, Stage2 cam, Verslagen tensioner, Sportster muff, 120 proof moonshine, Pirelli MT 66 tourers... and a chain conversion too ! IP Logged

Demin Serious Thumper Offline We need more chlorine in the gene pool Posts: 2435 Warren,Ohio Gender:	Re: Technical specs for Mini Speedo Reply #9 - 08/28/10 at 18:24:57 I usedan aftermarket/custom Harley speedo.I think they're 2:1.Fit right on the original cable too.
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