GStwin.com GS500 Message Forum

Main Area => General GS500 Discussion => Topic started by: mullethunter3 on December 08, 2009, 11:53:28 AM

Title: Mechanical to Digital Speedo - Is it possible?
Post by: mullethunter3 on December 08, 2009, 11:53:28 AM
Hey guys, I'm in a major rebuild of my 1992 GS right now. It's sort of a franken-bike of a 1992 and a 2004. That being said, I've replaced the engine with a 2004, rendering my tachometer useless because the new one is digital.

I don't want to buy another tachometer because a) they are still $100 on ebay and b) they look old and that's not the look I'm going for this rebuild.

I'm looking into either getting a Koso setup (probably not because they are too expensive) or more likely a gauge cluster off of another bike. I want to get one with a digital speedo readout and a standard dial type tachometer like the 04-05 GSXR 600 has.

My problem is that I have no idea whether or not it is even possible to get one of these clusters to work due to the mechanical speedo drive I have on the 1992. Has anyone done this before?
Title: Re: Mechanical to Digital Speedo - Is it possible?
Post by: dafatrman on December 08, 2009, 01:28:12 PM
Franken - bike, huh?  I call mine "Von Sukenstein" because I built it this summer with parts from seven bikes.  I also from time to time call it "Frankenpooter".  Sorry that my post didn't help, I just thought this would be funny.
Title: Re: Mechanical to Digital Speedo - Is it possible?
Post by: mullethunter3 on December 08, 2009, 02:31:19 PM
Has anyone put at least a KOSO on their bike? I've seen it done here, but that was 2 years ago now and I can't find it anymore. :(
Title: Re: Mechanical to Digital Speedo - Is it possible?
Post by: REAP on December 08, 2009, 03:48:09 PM
I used the KOSO RX2 & it looked awesome. Really easy to install, had no problems with it at all. I did have them on my 07 GS, not too sure about your situation but on mine it was easy. I've tried to find pictures of it on my bike but i can only find the remains of it after my crash :(. Good luck with with your bike!
Title: Re: Mechanical to Digital Speedo - Is it possible?
Post by: mullethunter3 on December 08, 2009, 04:07:15 PM
REAP, how did you hook up the speedo? I think both of ours are mechanically driven from the front wheel. Isn't a KOSO digital? How did you make the conversion?

Thanks!
Title: Re: Mechanical to Digital Speedo - Is it possible?
Post by: Paulcet on December 08, 2009, 04:47:56 PM
Yes, it is possible.  Vapor from Trailtech, or Veypor, or KOSO are all going to be the easiest, I think.  Tach gets a signal from a coil wire or ignition sensor wire.  Speedo gets a signal from a magnet attached to the wheel.

My bike has a set of gauges from an SV650, which is all electronic.  Dgyver adapted the SV speed sensor to fit, and the tach I believe was attached to a coil wire.  Any electronic tach from a 2 cylinder bike would probably work...
Title: Re: Mechanical to Digital Speedo - Is it possible?
Post by: psyber_0ptix on December 08, 2009, 04:59:03 PM
most universal speedo's out there will be a fork mounted magnetic sensor and a magnet countersunk into the rotor, or a magnetic rotor bolt.

mine is a acewell gauge with tach and speedo. The tach is driven off the CDI or the white wire on the left coil pack. I needed to use a 1 MOhm resistor for it to read correctly.

The speedo was an easy job. just have to figure out the mounting for the sensor and magnet configuration to the rotor. You then need to enter the circumference of the wheel/tire as it will depend on your rim size, tire, and sidewall aspect ratio to give a proper reading.

IIRC gsxr and or SV speedometers are driven off a sensor located by the front sprocket?
Title: Re: Mechanical to Digital Speedo - Is it possible?
Post by: Paulcet on December 08, 2009, 06:39:59 PM
Quote from: psyber_0ptix on December 08, 2009, 04:59:03 PM

IIRC gsxr and or SV speedometers are driven off a sensor located by the front sprocket?

GSXR and maybe later SV speedometers are driven off a sensor located by the front sprocket.  Older SVs had a wire going down to the front wheel hub.
Title: Re: Mechanical to Digital Speedo - Is it possible?
Post by: REAP on December 09, 2009, 03:38:13 AM
I hooked up all the wires from KOSO into the existing wires that came out of the old speedometer. For the speed it just uses magnets that run off the front wheel. As i said before, really easy to install. They give you a diagram and a "how to" for the install.
Title: Re: Mechanical to Digital Speedo - Is it possible?
Post by: dgyver on December 09, 2009, 06:49:34 AM
Get the signal for the electric tach from the black/yellow wire that goes to the right coil.

As for the speedo, GSXR's gages use a Hall Effect sensor which pulls from the front sprocket. A signal can be generated at the front wheel (like I did on Paulcet bike with SV gauges) But on GSXR gages, the signal pulses from the front sprocket would be at different intervals from the front wheel due to the rotational speed difference. Not sure how to over come this with a GSXR gage.

1st gen SV's get the speed signal from the front wheel.
Title: Re: Mechanical to Digital Speedo - Is it possible?
Post by: seamax on December 09, 2009, 01:04:57 PM
Quote from: dgyver on December 09, 2009, 06:49:34 AM
Get the signal for the electric tach from the black/yellow wire that goes to the right coil.

As for the speedo, GSXR's gages use a Hall Effect sensor which pulls from the front sprocket. A signal can be generated at the front wheel (like I did on Paulcet bike with SV gauges) But on GSXR gages, the signal pulses from the front sprocket would be at different intervals from the front wheel due to the rotational speed difference. Not sure how to over come this with a GSXR gage.

1st gen SV's get the speed signal from the front wheel.


do you have a write-up fot the sv gauges somewhere?
Title: Re: Mechanical to Digital Speedo - Is it possible?
Post by: dgyver on December 10, 2009, 06:16:53 AM
Quote from: seamax on December 09, 2009, 01:04:57 PM
Quote from: dgyver on December 09, 2009, 06:49:34 AM
Get the signal for the electric tach from the black/yellow wire that goes to the right coil.

As for the speedo, GSXR's gages use a Hall Effect sensor which pulls from the front sprocket. A signal can be generated at the front wheel (like I did on Paulcet bike with SV gauges) But on GSXR gages, the signal pulses from the front sprocket would be at different intervals from the front wheel due to the rotational speed difference. Not sure how to over come this with a GSXR gage.

1st gen SV's get the speed signal from the front wheel.


do you have a write-up fot the sv gauges somewhere?

No.
Title: Re: Mechanical to Digital Speedo - Is it possible?
Post by: Roadstergal on December 10, 2009, 09:46:39 AM
Quote from: dgyver on December 09, 2009, 06:49:34 AM1st gen SV's get the speed signal from the front wheel.

2nd gen SV650s do, too.  SV1000s don't.  The advantage of reading off of the front wheel is not having to get a speedo healer when you regear...
Title: Re: Mechanical to Digital Speedo - Is it possible?
Post by: dgyver on December 10, 2009, 10:44:43 AM
Quote from: Roadstergal on December 10, 2009, 09:46:39 AM
Quote from: dgyver on December 09, 2009, 06:49:34 AM1st gen SV's get the speed signal from the front wheel.

2nd gen SV650s do, too.  SV1000s don't.  The advantage of reading off of the front wheel is not having to get a speedo healer when you regear...

Thanks. I am not familiar with them.