Swapping an '80 S model speedo, 85 to 140mph?

[Frank Z.]

Anyone ever swapped-out a 1980 Cooley 85mph speedometer (aka: Jimmy Carter Special) for an earlier '78/'79 E or C 140mph one? Wondering about the odometer reset stem that surfaces out of the S dash, and if there's a known mod/swap one can do to marry the stem components from the respective gauges. (Parts fiche indicates that the speedo is specific for S models, and of course rarer than hen's teeth.)

Also, any other issues with speedo accuracy, interchangeability, etc. i need to know are welcome.

Thanks in advance!

[7981GS]

Rustybronco would be the gauge expert to ask my friend.

Eric

[hampshirehog]

I don't think it can be done easily at all.
Have you thought about putting a kph converter on there and using the KPH part of the clocks as speedo in mph? It'll throw the odometer to pot but show you can do more than 85mph!

[chuck hahn]

I have the 140 that I am willing to donate for Franks conversion. The thing is that they are the 78 E/C models with the reset stem comming out the left side of the guages. I am about 99 % sure that all will work normally as far as the internal gearing of the E/C ones reading correctly off the existing gear drive on the axle. The thing we need to know is ( other than drilling the hole for the Cooley stem to come thru the guage face ) Can we just swap the internals for the trip meter FROM Franks speedo TO the 78 guage and be all set??

[chuck hahn]

Whats your accessment Dale??

[hampshirehog]

This chap is cheap enough to buy and play around with. You might be able to swap the guts of the speedo over thinking about it.

http://www.ebay.co.uk/itm/Suzuki-GS1000-Speedometer-34101-49081-/160775755432?pt=Motorcycles_Parts_Accessories&hash=item256efb56a8

[Frank Z.]

This chap is cheap enough to buy and play around with. You might be able to swap the guts of the speedo over thinking about it.

http://www.ebay.co.uk/itm/Suzuki-GS1...item256efb56a8

Whoa... Nice find! Wish she went to a buck-forty.
Hmmm...

Awaiting rustybronco's evaluation...

[rustybronco]

You take apart a few gauges and you become some sort of an an expert 'eh?

Keeping in mind I've never been inside of a Cooley's speedometer, here's my take on the subject from what I can see.

Unless until you take that gauge apart, there is no way of knowing if they used different sized (length/diameter) gears inside the speedometer and whether or not they can be interchanged. If the two plastic gears do interchange and I'm speculating they will, there is still the issue of remaking a new gauge face with markings to 140 Mph. From what I gather, reproduction decals can (will) make a new face for you.

I suspect the 78~79 gauges innards will interchange quite nicely irrespective of the angle drive used to reset the trip meter.

Take it apart and find out...

(sorry for the bad tripmeter location information, Vicodin's cloud your thinking)

[chuck hahn]

taking it down isnt a problem..I do however wonder how the trip meter reset ( #2 in the schematics ) "links" to the trip meter stem. The schematics dont show the speedo very well to get an idea as to what the actual configuration coming out of the speedo housing actually looks like. Anyone ( Eric ) have one sitting on the bench that can post some pics or insight???

[chuck hahn]

Dale...the plan was to use my guage faces and inners...or better yet, the entire guage and do the mods and then transplant to Franks dash.

[Frank Z.]

All good info folks. I now see the odo/trip complication... now why would Suzuki do dat??

Reference pics of the subjects in question:

[rustybronco]

Chuck, I doubt Suzuki would have used anything different that the usual short threaded metal piece sticking out the side of the speedo for the brass extension to screw onto. The brass piece will be different to accomodate a gear for the right angle drive arrangement.

[Nessism]

Edit: Frank's photos showed up while I was typing this note...

The 140 and 85 mph speedometers are interchangeable. The cable drive ratio is the same coming from the wheel. These speedos are unique to the S though, with a special odometer reset mechanism device angling off the side of the case. I'm pretty sure an early GS1000 speedo would work as long as you don't care about resetting the odometer.

It may be possible to crack open the S speedo housing and implant the early speedo guts, but I'm not sure how it all works with regard to that reset mechanism.

[rustybronco]

All good info folks. I now see the odo/trip complication... now why would Suzuki do dat??

I knew about that little issue. There were other gauges used a similar cutout for the tripodometer instead of the normal one slot cutout.

[rustybronco]

, but I'm not sure how it all works with regard to that reset mechanism.

I do believe the angle drive arrangement to be separate from the actual gauge by looking at that ebay speedo.

Just uncrimp the bezel, remove the c-clip from the backside of tripmeter's knob 'shaft' and swap the guts. (I suspect)