Short and Fast....Or Long and .......fastish!!

drumsmasher
drumsmasher Posts: 241
I'm fairly new to this roadie stuff having been mountain biking for a few years. I am trying to get my average speed up from around 18 mph over a couple of hours and need some advice! (please)

Do I try and blast out short rides with eyeballs out or do i just keep plugging away on longer distances as quick as i can. My average seems to be the same whether i go for 2 hours or 4 and where i live means that even on a short blast i have a few big hills to climb from my house which obviously slows my average down!

Also...The averages i read on here...are they based on a generally flat ride or the usual hilly rides that even themselves out over a couple of hours?

Cheers for any advice you can offer.
Another tree...another cracked rib!!