A search hasn't found the answer, hence what is very almost a repost. Sorry for cluttering the place.

I have mounted a temperature sender in the bottom of a rocker cover (right hand).

After a twenty minute drive home having been left to stand for five or so minutes it indicates an oil temperature of about 95 celcius (while throughout the drive it will indicate 60 celcius, the bottom of the scale). If you start the engine and idle it from a hot stand (ie long trip, ten minutes engine off, then fire it up) the indicated temperature drops slowly down to about 65C.

Would I be right in thinking the air flow over the sender is cooling it putting the reading off? If this is correct would several layers of insulation tape fix the problem, should I try to create a sheild from the air flow?

terpineol,
whilst the engine is running, there's a temperature gradient across the metal of which the cylinder head is formed, with over 200C on the 'hot' side...
When you switch the engine off after a run, there's no longer any flow of air cooling the outer surfaces, nor is the oil circulating to make its contribution to the cooling process, so the temperature of the 'outer' surfaces will increase.
This is why you are seeing a higher reading on your gauge after stopping, in much the same way as the needles on the cylinder head temperature gauges used on the 2CV racers will rise _after_ the engine is switched off.

There's probably a good case for easing off on the throttle for the last mile or so of a fast run on the motorway, when planning to stop for petrol, to lower the general temperature of the engine...

ken.

My Oil Temp/Pressure setup, prices quoted in Aussie dollars...
Accurate oil reading as the sensor is in the oil flow as it passes into the filter, Increased oil capacity (if a larger filter is used) means cooler running temperatures. Been in use for over a year now with no problems or leaks.

Cheap gauges found @ http://crazysales.com.au $36:
Oil Temp gauge, 50-150ºc.
http://crazysales.com.au/index.php?productID=365

Oil Pressure gauge, 0-150psi.
http://crazysales.com.au/index.php?productID=363

Oil Sensor adaptor (Sandwich plate) $19.90:
Ebay Item 120459262449

This is the important piece
Brass Thread reducer, M20 to M16 $4.38.
AWM Electrical (electrical conduit fitting).
http://www.etscc.co.uk/jkcm/plugins/ProductsInCategory.aspx?cat=3744

With this setup you can use any size oil filter, i am currently using Valvoline VO2, 1ltr capacity

Cheers
Harley