Changing speedo dials

[Guest]

Hi guys
I have a 1982 GSX 1100e which is in kph only. I want to put this dial/face onto another speedo unit that i got from usa which is in miles and kph. The needle stop for both dials is at the 3 o'clock position but the speeds are totally different. As my speedo goes to 240kph and the usa one goes to 140kph. My question is will it still read right with the kph dial on the usa speedo, or is there different gearing /ratios for the speedo where it fits into the front wheel? Any help appreciated.

[Nessism]

Speedo gearbox is same. Not sure what particular gauges you are looking at, but most are internally compensated and designed to be interchangeable.

[OLDENUFF]

Not sure if I'm reading it right but, if you are talking about swapping the faceplate from a 240kph on to a 140kph guage, your readings will be way off. Bob

[Nessism]

Not sure if I'm reading it right but, if you are talking about swapping the faceplate from a 240kph on to a 140kph guage, your readings will be way off. Bob

Good point. You can't change the face to one with different divisions and expect the gauge to be accurate afterwards.

[carvan40]

That's what i thought which leads me to believe that the gearing is different for the speedo drive at the front wheel, or is it in the internal workings of the speedo itself

[Weapon]

front wheel would be the simplest from a manufacturer standpoint. I believe as long as you change that as well the dash would be accurate.

sorry I just necroed this old post. I forgot I was searching old threads

[posplayr]

front wheel would be the simplest from a manufacturer standpoint. I believe as long as you change that as well the dash would be accurate.

sorry I just necroed this old post. I forgot I was searching old threads

A strange couple of posts. The total sweep of the gauge should represent the same highest velocity regardless of units. In fact I'm pretty sure my 140 mph gauge has both kmh and mph on the same face. So why different gearing would be needed is beyond me?

[Weapon]

he wasn't talking about a 140 mph gauge, I read it as a 240 KPH gauge or a 140 KPH gauge. which would require different gearing at the wheel as you are correct the sweep is the same

[posplayr]

he wasn't talking about a 140 mph gauge, I read it as a 240 KPH gauge or a 140 KPH gauge. which would require different gearing at the wheel as you are correct the sweep is the same

I just looked at my 140 speedo and the 220Km/hr trick is just below the 140 Mph tick which I assume if we do the conversion is correct. That is the last ticks and presumable near the max sweep (I did not try and measure the angle).

I see no reason for gearing change unless it is because it is a 240 kmph speedo reads higher than v.s. 220 kmph marked on the 140 mph speedo at the same full full sweep?


Ed state above the speedo gear on the wheel is the same, and that the gauges will read correctly no matter the speedo gear (of course a wheel/tire change is something different).

You stated the sweep is the same, coupling that with Ed's statement the conclusion is that face plates can just be swapped. No?

[Weapon]

I got the impression he was talking about this gauge though which as far as I know is off of a non export 250 or 400 katana.
I might be wrong though and the op just confused mph and kph
edit: went back and reread his original post and he does say 140 kph but it must be a mistype as he is describing a US dash.
so not only did I necro an old post but muddied the waters as well! .... go me!
apologies

[posplayr]

I got the impression he was talking about this gauge though which as far as I know is off of a non export 250 or 400 katana.
I might be wrong though and the op just confused mph and kph

As my speedo goes to 240kph and the usa one goes to 140kph.

This is from the OP, yes a 85mph change to a 140 mph change (and Kmph equivalents) at the same sweep angel needs a gear change, but even that is apparently inside of the speedo; the axle gear ratio is the same.

Now I understand the thread.

[Weapon]

This is from the OP, yes a 85mph change to a 140 mph change (and Kmph equivalents) at the same sweep angel needs a gear change, but even that is apparently inside of the speedo; the axle gear ratio is the same.

Now I understand the thread.

that is good information for me then to know that those non expo speedos are off limits. I always assumed they just changed the face and the wheel gear when they brought those little kats out. I figured it would be a good source for a dash if I could not find a north American one.

[TopGun]

The GS850 I'm restoring which was imported to the UK from America had a seized speedo which I replaced with the instrument mechanism from an old Hinckley Triumph one just to get some movement. This seems to have a different gearing and when I looked more closely the Suzuki dial only goes upto 85mph with a special marking for 55mph which I believe is the USA national speed limit (?). I'm wondering why it only goes upto 85mph and what would happen if you went over that speed, presumably just go to the stop and stay there. I believe these bikes will do a lot more than 85mph.
It seems to be showing speeds that are about half the actual amount ( i.e. 30mph shows 15mph ). which I can live with for the moment.

[Grimly]

From what I know, all GSs and probably all Japanese bikes of that era had the same speedo drive gearing, namely 2240 revs per mile. This makes it easy to fit another speedo head from another make, but obviously Triumph has a different ratio.
As far as exceeding 85mph on the speedo dial - if you do that, your feet will explode and your house will catch fire, so don't do it.

[TopGun]

Further to this is that the new main 'movement' seems to give readings on the old 85mph dial which are about ½ the standard dial figures which I can live with now I have a working speedo. I have done a check on the mileage indicators they are about right.
I never go above the speed limits any way but I will heed Grimly's sound advice !