Originally Posted by
dangerd
Like mprelaw mentioned - try riding with higher cadence in an easier gear that will help.
Yeah, this. And start trying to understand what it means to "pedal circles". Clipless is a gold mine of efficiency but it can be subtle.
Also- if your seat height was perfect without cleats, you'll need to raise it a bit wearing cleats. But let's be realistic here. 3 weeks in, your seat height is almost certainly too low regardless, unless you were professionally fit.
Low cadence and low seat height will make muscles burn, and likely lead to other issues as you continue to increase mileage. To get a feel for ballpark proper seat height, do the "leg extended w/ heel on pedal" method wearing regular shoes. Note your leg angle while pedaling the full stroke. Then put on your cleats, and adjust the seat to approximate that leg angle while clipped in. You'll have to move the seat higher to compensate for cleat/pedal stack up.
Keep it up! The payoff is huge.