GStwin.com GS500 Message Forum

Main Area => General GS500 Discussion => Topic started by: amkluttz on December 05, 2012, 10:46:22 AM

Title: Speedometer Drive Ratio
Post by: amkluttz on December 05, 2012, 10:46:22 AM
I am wanting to change out the speedometer and tach on my bike to something smaller.  I would love to have a Trail Tech or Koso but can't justify the money to the wife and I don't mind the analog gauges or the cable drive.  I'm looking for something smaller that I could mount in a similar location to stock but maybe lower and tucked a little behind the headlight.

Something like this...

(http://www.ellaspede.com/wp-content/uploads/2012/03/EB007-GS500-Front.jpg)

I contacted them about the gauges they used but found they are only available in KPH.

I have been looking at cheap cruiser replacements.  I know there could easily be a problem with the cable drive not fitting the gauge along with a myriad of other problems.  My question is does anyone know the drive ratio of the GS500 speedometer to the wheel?  A lot of the drive ratio's on these gauges are 2:1 which I've been told means two revolutions of the wheel to one revolution of the speedometer.  Could I simply spin the front wheel once while the cable was pulled from the speedo to see how many times it spins? 

I'm looking at these:
http://www.amazon.com/Bikers-Choice-Speedo-Indicator-Light/dp/B000GZVHH4 (http://www.amazon.com/Bikers-Choice-Speedo-Indicator-Light/dp/B000GZVHH4)
http://www.amazon.com/Baja-Designs-Analog-Backlit-37-0002/dp/B000GZL5WQ/ref=sr_1_3?ie=UTF8&qid=1354729043&sr=8-3&keywords=motorcycle+speedometer (http://www.amazon.com/Baja-Designs-Analog-Backlit-37-0002/dp/B000GZL5WQ/ref=sr_1_3?ie=UTF8&qid=1354729043&sr=8-3&keywords=motorcycle+speedometer) 

Also, I understand that these gauges are cheap and most likely are junk and that I would be better off to save my money and get a Trail Tech Vapor.  My wife and I are on a budget and she has already purchased all of my gifts for this year (Christmas and Birthday are really close) or I would ask for a Vapor.  I'd like to give this a shot but if someone out there has already experienced this or knows why this won't work then I would rather waste time researching than money.
Title: Re: Speedometer Drive Ratio
Post by: sledge on December 05, 2012, 10:53:58 AM
Quote from: amkluttz on December 05, 2012, 10:46:22 AM
Could I simply spin the front wheel once while the cable was pulled from the speedo to see how many times it spins? 


Yes.
Title: Re: Speedometer Drive Ratio
Post by: jestercinti on December 05, 2012, 11:07:33 AM
This may help for small digital units...http://en.wikipedia.org/wiki/Hall_effect_sensor

As far as the ratio goes, I remember seeing it on the board, but I cannot find it now.
Title: Re: Speedometer Drive Ratio
Post by: jestercinti on December 05, 2012, 02:27:14 PM
Ok, found it.  Read this:  http://gstwins.com/gsboard/index.php?topic=59660.0
Title: Re: Speedometer Drive Ratio
Post by: rharding91 on December 05, 2012, 02:33:03 PM
I dont think my speedo is even accurate. I was cruising along on the 60 a freeway here in HOV lane and a Honda Civic was next to me and had a big LED speedo I could see through window. My speedo said 92 or something and the civics said just 80. You guys know how to check that?

Sorry to be off topic haha just thought of that while reading your thread.
Title: Re: Speedometer Drive Ratio
Post by: crzydood17 on December 05, 2012, 03:51:39 PM
GS 500 speedos are normally 7-10% optimistic, I normally go 80ish in a 70 and so on.
Title: Re: Speedometer Drive Ratio
Post by: Big Rich on December 05, 2012, 04:12:45 PM
The ratio is 2240:60. The other ratios are 2:1 and 1:1 which are used for Harley, newer Triumph, etc. Check out www.dimecitycycles.com for metric speedos.......but those small speedos have had some quality control issues lately.

The most accurate ones are digital, but you can also check your current speedo with any GPS unit - either on a smart phone, hand held, or an automotive type (all in a tank bag or similar).
Title: Re: Speedometer Drive Ratio
Post by: snOhio on December 05, 2012, 05:11:55 PM
Quote from: rharding91 on December 05, 2012, 02:33:03 PM
I dont think my speedo is even accurate. I was cruising along on the 60 a freeway here in HOV lane and a Honda Civic was next to me and had a big LED speedo I could see through window. My speedo said 92 or something and the civics said just 80. You guys know how to check that?

Sorry to be off topic haha just thought of that while reading your thread.

I had this problem where i would hear a terrible noise from somewhere in the speedo/cable/wheel assembly, the needle would shake, and read way high.  i fixed it by pulling the speedo cable out of both ends, lubing it with white lithium grease, and making sure it was firmly seated in both ends.  no issues since.  i can't tell you exactly what it was that i fixed, but a good remove>clean>lube>reassemble couldn't hurt.
Title: Re: Speedometer Drive Ratio
Post by: amkluttz on December 05, 2012, 08:20:08 PM
You guys are awesome.  At least I learned something out of all of this.  I had no idea why you would use a 2240:60 ratio or what it meant.

I went home and jacked the front of the bike up (while on the center stand).  I pulled the cable out of the back of the speedo and marked it along with the wheel.  I spun the wheel one complete turn and as far as I could figure it spun the cable 2.5 times.  I guess none of that matters since I don't have to guess the ratio any more.

Because of curiosity I couldn't just let it go at that.  So now my entire gauge cluster is in pieces but at least I know how to take it apart.  I'll keep this updated if I decide on anything.  It's looking more and more like saving my money for a vapor is the right idea.
Title: Re: Speedometer Drive Ratio
Post by: crzydood17 on December 05, 2012, 10:03:04 PM
2240:60 O-o
1120:30 O-o
560:15 O_o
112:3 WOHOO

Lowest common denominator...
Title: Re: Speedometer Drive Ratio
Post by: amkluttz on December 06, 2012, 10:38:24 AM
It seems the 2240:60 ratio adds some dollar signs to the price of the gauges.  Most of them are around $80-$90 and that still leaves me without a tach.  I did see the one from dimecitycycles.com for $45 but it doesn't have a trip and without it I would run out of gas.  I found the Vapor 75-704 Stealth for $95 shipped on amazon; Seems like a no-brainer.  So thank you all for helping me with this information. 

I think for now I am going to try to play around with the stock gauges since I have them in pieces anyway.  I'm going to try to stuff them behind the headlight and almost flat and make a new faceplate.  They appear to be fairly weatherproof even without the black bucket they sit in so my plan is to paint them black underneath and mount them.  If I hate it I can always return it to stock.  I hope to work on it tonight and if I figure anything out I will post pictures.
Title: Re: Speedometer Drive Ratio
Post by: rharding91 on December 06, 2012, 11:30:32 AM
http://phoenix.craigslist.org/wvl/mcy/3395681933.html

Saw this on my local CL
Title: Re: Speedometer Drive Ratio
Post by: amkluttz on December 06, 2012, 07:59:34 PM
My wife went out tonight for work so I had some time to play in the garage.  Here's where I'm at...


(http://i1057.photobucket.com/albums/t394/amkluttz0819/GaugePlate.jpg)

(http://i1057.photobucket.com/albums/t394/amkluttz0819/GaugePlate2.jpg)


If everything works out it looks like the gauges will lay down and be a tucked a little behind the headlight.  I am going to have to figure out where I want to put my indicators.
Title: Re: Speedometer Drive Ratio
Post by: amkluttz on December 08, 2012, 08:36:46 PM
I finished!  I made my own LED indicators.  First ride today and so far I love it.  They sit in a pretty perfect location.

(http://i1057.photobucket.com/albums/t394/amkluttz0819/Bike%20Pics/GaugePlateComplete.jpg)

(http://i1057.photobucket.com/albums/t394/amkluttz0819/Bike%20Pics/GaugePlatefront.jpg)

(http://i1057.photobucket.com/albums/t394/amkluttz0819/Bike%20Pics/GaugePlatelights.jpg)

Title: Re: Speedometer Drive Ratio
Post by: mustangGT90210 on December 09, 2012, 12:16:34 AM
Great execution!

I run a Drag Specialties 2.4" mini speedometer. Those run in the $50 range and I love it. The needle movement is extremely smooth, never shakes, etc. I'd definately check it out if you're still looking for new gauges
Title: Re: Speedometer Drive Ratio
Post by: iclrag on December 09, 2012, 11:29:13 AM
Thats a pretty good looking setup!


and yes, ive heard everything from 7-12% difference for the GS speedo, i go about 67 ish in a 55 to not get passed (local highways are only 55 :icon_sad: so that puts me at about 60ish miles per hour which is about 10% off