Granted, I had a hip replacement between my DF riding, and my new trike, but I have also found that both my distance, speed, and cadence have gone down on the trike. The plus side is that I am much more comfortable on the trike, and aside from knee pain, a vast improvement.

I was not any kind of lightning bolt on my DF - 25-30 mile daily rides at a 10-11 mph average, but now my longest ride has been 20 miles at 7mph average on the trike.

My point here? You're not alone in what you've noticed. We each must decide what we want, and for me, I'll give up the speed for the comfort. Everything I have read since last OCT has said a 2-3mph speed drop seems to be a fact. Granted, I only have bout 300 miles so far on my trike.