Finally got round to getting some spd shoes (for the road bike) yesterday and other than a quick test, had my first ride with them today. Loving the extra power you can get from proper circles, but I've noticed they're really making my feet ache - it's the bit between the ball and the heel, whatever you call that (sole?). It got so bad I had to stop for a few minutes to let them rest.
Shoes are Specialized BG Sport, pedals are Shimano A530. As far as I can tell they fit me fine - any looser and they'd be slipping off, much tighter and they'd be crushing my feet. The soles feel really stiff so I dunno if it's lack of support. It feels like the cleats are aligned properly, my knees/feet don't feel twisted or anything, and the pedals have a bit of side-to-side play so should correct any small misalignment?
I really want to like these as £70 is a lot for a pair of shoes, but at the minute I'd rather ride flats to stop the pain :\
It's the stiffness of the soles. Your feet are used to having much more flex and roadie shoes hold them in a bit of a vice-like grip. I bought myself a pair of carbon-soled Sidis in the summer and had exactly the same problem for a while. I still get it a bit despite wearing them 4 times a week but it does diminish over time. I notice it for the first 15-20 minutes of a ride then it seems to go away. Persevere and your feet will become accustomed to it.
They're actually mtb shoes as I was gonna try it for xc as well. I guess they are still very stiff compared to normal shoes though.
Make sure they are not too tight, it's easy to really belt them on first time out. They only need to be tight enough to stop heel lift.
I run two insoles to mitigate this.
[two in each shoe, not two in total....]