Is it ever the bike?

[nscrbug]

30km/hr is pretty good after only 6 month of riding. it's approx. 20MPH.

One thing I've noticed over the years is that our improvement is not necessarily linear. it tends to be more like staircases. See some quick improvement. Get stuck at that level for a while. Then suddenly show some improvement again. While you are in the plateau, your body is settling into and getting used to the new fitness level.

Just keep riding and once a month or so go for extra hard or longer distance. This will help you get past the plateau.

Again you are doing pretty well.

X2! Actually, if my calculations are correct, it is more like 18.6mph, but still...that is damn speedy, in my book. I would LOVE to average 18mph for an entire ride...but that has yet to happen. I live and ride in a suburban sprawl, with stoplights and stop signs at every corner...which doesn't do much for my average speed, which currently hovers around 15.5mph.

I think you're doing great and I would be super proud of an 18+mph average, if I were you.