Join Date: Jul 2008
Location: dartford, , United Kingdom
Model: gl1100 1980 mileage 150,000
to find out the true temp of the water try getting hold of a domestic radiator temp gauge. Their cheap and fit to a hose with a spring round the hose. Take the bike out and check the water temp at various stages of the journey. I would put it on the lower hose so you have some idea of what the water temp is like when the rad has finished it's job.
If you like use dave 0430's idea and try again with the gauge on the upper hose.
I suspect he is correct as usual but this may well prove to you that it is indeed a problem you need to sort.
keep the old girl on the road
1980 gl1100 A canadian import. mileage 150,000 +