I do not go fast, but I can ride 25 or 30 miles and recover quickly.

On some rides, especially against the wind, my HR gets into the 140s and stays there, even though I'm only going 12-13 mph. I'm breathing hard at that rate, but I'm not gasping for breath. I'd like to get faster, but based on experience, too much time in the 140s wears me out, even though I'm not going fast, so whatever speed I'm going, if my HR is 140+, my best bet is to slow myself down..

At 75, my max HR is pretty close to the mid-140s. I doubt I have the endurance to do an LTHR test, nor do I have cash available for such a test, so I don't know what my max is.

Anybody else seeing this sort of igh HR and slow speed?

If have to just keep at it, I'm OK with that. I do get faster as a season progresses. But I'd like to be able to sustain higher speed. Right now the casual group in the local club is too slow, and the next group is too fast for me.

Thanks for your counsel.