I believe a temp sender can be fitted to the water drain plug on the k100, but can you then use normal gauges, theres a few on ebay and not too bad a price.

I believe they just need a 12v supply with the temp sender unit providing the earth via certain resistances, if this is the case then surely a sender and gauge from anything can be used?
what size sender unit (thread) do i need to screw into the drain hole?


Or am i thinking wrong?

Yep you can get the sender from motobins/works
heres the link to the bins page
http://www.motobins.co.uk/bmw-parts.php?model=K%20Series

Part No.87042


When I put an RT fairing on my RS I bought SH gauges from Ebay and the sender from
bins and did the wiring mods myself

Not sure how accurate non bmw gauges will be but as most of these things work in similar ways
(ie as you say by the sender controlling the flow of current to earth dependng on temp
which in turn deflects the gauge needle)
its probably worth looking at and you can alays keep an eye out for sh ones on Ebay
if your not happy with the results

badgerdid wrote:I believe a temp sender can be fitted to the water drain plug on the k100, but can you then use normal gauges, theres a few on ebay and not too bad a price.

I believe they just need a 12v supply with the temp sender unit providing the earth via certain resistances, if this is the case then surely a sender and gauge from anything can be used?
what size sender unit (thread) do i need to screw into the drain hole?


Or am i thinking wrong?

you're totally right. I did it on my K 100 RS