Hey there Blue (been meaning to say, excellent avatar!)

36/38km/hour is what the top women in my age cat average (39-45yrs) in a Time Trial

In a road race, of course, you might get a higher average because of the benefits of the pelaton.

Rolling terrain, specifically downhills can increase your speed of course... my fave downhill for speed is steep and straight - only about 200 metres but with some 500 metres stretching in front so you can slow down before the next corner... I have got over 60km/hour going down there... but mostly my downhills are windy and I keep myself to 35/40...

I can ride on the flat at about 40km, but not for very long. I have excellent power output but not much endurance... endurance is what I am working on.

Like you, Blue, I don't want to embarrass myself... or more importantly, don't want to embarrass my partner and our boys at the club... so have yet to do my my first club race... I think I'm almost ready... this summer I hope...