Hello there,
Does anyone have any advise before i open up the clocks on my r80gs. my speedometer dosn't work (its not the speedo cable because the mileage guage works fine). I remember trying to open it up before but failed miserably ( i was afraid i was going to break something )...has anyone tried to do this before???Does anyone have any helpful tips?Thanks in advance.
Barra O Luanaigh
:confused1:

The balck piece at the top need s to be (carefully .. very carefully) expanded ... choose the bit at the back so you don't see it when you reinstall it. Most ordinary mortals will damage it . And geting a new one is difficult. You are probably best off finding a speedo repairer. Once you have it opened .. you may =find a broken hair spring, bearing gone .. you got the watch making skills to fix it? I did 3 months as a watch maker .. it was not easy and my eyes anit what they used to be.

Fitting a bicycle speedometer is easy , and they are cheaper than getting your original speedo repaired!

__________________
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Regards Frank Warner
motorcycles BMW R80 G/S 1981, BMW K11LT 1993, BMW K75 G/S

Hey Frank,

sounds like you're stuck in Oz instead of doing the trip you ha planned via western Africa to Europe. I was expecting to catch up with you at the HU meeting in the UK in June. You won't be there, will you?

Hans

__________________
Only when we pause to wonder
do we go beyond the limits of our little lives.
(Rod McKuen)

Thanks Frank,
Sounds messy alright.I'm not much of a watch builder but as the bike is off the road for a while i might give it a bash,,,,
its been annoying me for a while,,,,thanks for the tips and the time,
Barra O Luanaigh

Whatever you are thinking, don't' do it.
You will have no success trying to fix it yourself. Even if you get it to work you will find the calibrating to be out completely. this needs to be done on a special instrument.
The reason it is not working is most likely because the gears is ceased and one or more gears might have to be replaced.
The needle is very delicate and will brake by just looking at it to hard and will definitely be out of calibration just touching it.
I would recommend disconnecting the speedo cable to prevent further damage until you can get it fixed by a professional and buy yourself a cheap bicycle speedo because they can do exactly the same job.
A new speedo for these older bikes is about double the price of one for a new GS, so don't fiddle with it even if you think you can fix it.

Errrr no.
The gears are for the odometer.. that is functioning.

The speedo is direct drive to the drag cup. The bottom bearing (and mount for the cable drive) is plastic (on teh G/S and onwards) and can ware out. Easiest to replace that with a brass piece from an older model bm .. they saved weight (and cost) by going with the plastic bit. And the hair springs can go .. and the needle bearing .. all fiddley stuff. None of the parts are avalible from bmw... a wercked old bm speedo may be a source of parts .. if you can find one.

Calibration can be achieved using an electric drill .. but you'll need to know the speed of the drill (and that will be 'locked' to teh mains frequency - provided it is not a varible speed model) the tyre diameter and the geat ratio on the hub... or in the gear box and final drive for a bm.. - the easiest these days is to use a gps and compare. Adjusting teh reading .. well it is not simple. Depenmds on the adjustment required - if a constant offset - moveing the needle on its splined spindal is easiest. Non constant .. well you have the hair springs..

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I hope to be in Africa in a week or two... been saying that for a while. I'll definatly be at the Isle of Man TT, and the uk hu meeting following it..

__________________
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Regards Frank Warner
motorcycles BMW R80 G/S 1981, BMW K11LT 1993, BMW K75 G/S