There are several causes of knee pain on your bicycle
1. Cleat position. Your feet are not meant to be parallel and nor should your cleats be set parallel.
Check to see how your foot position is when stood relaxed and after you take a few steps.
Some of you will have one foot turned out more than the other, and some one foot more turned in than the other, your cleats should reflect your natural foot position.
Also where your cleats sit, in my opinion, you get more power if they are closer to your 1st metatarsal heads of your toes, the Ball of foot, as that is where you gain most power from, however others may conclude differently. However this depends on how your foot functions and the over compensation pattern your body runs into your feet, will affect what works for you.
2. SPDs size and width. To check if your SPDs are correct width for you either take shoe liner out if there is one and place your foot on top of it, or, place your foot on top of your SPD and look to see where your toes are.
If your toes fall outside of the shoe then it is too small and squashing your feet into said shoe reduces your power. Squished feet mean the ball of big toe can not function as intended and that inhibits it’s connection with your butt, glute muscles, which is the main powerhouse driver. This is a problem with most footwear and the big impact it can have on your body's performance.
3. Your knee is a weak point due to an over compensation 123 pattern running in your body.
See the picture:- Area 1 is the hips
Area 2 abdomen and thighs
Area 3 lower leg and upper body
We should fire outwards from area 1 first, then area 2 and 3. But our body has this inbuilt overcompensation capability so it can can protect itself in times of stress, fight or flight state which is a short term state, but somehow we create this to be our normal functioning state.
So majority of knee pain issues are running a 223 or 233 pattern, this is maybe not the case for everyone and this is just an example of how the body overcompensates not a diagnosis.
223 pattern is the area 2, thigh, doing area 1 job, hip flexion, and it’s own job of looking after the knee, area 2. This means the tendons and ligaments in the knee end up as vulnerable weak points due to the thigh muscle shortening, tightening and driving upwards as the hip flexor, area 1. When this area gets over tired then you start to notice the pain.
233 pattern is area 2 still doing area 1 job, thigh doing hip flexion, but the lower leg area 3 is looking after the knee function, which is an better overcompensating pattern than the other pattern but still inhibits your body’s performance as the muscles are still doing another function instead of or as well as their own, which they are still shortening, tightening and driving upwards instead of explosive power outwards.
Simple things to help the 123 pattern: - belly breathing,
- passive resting squat, best barefoot with either magazines or books under heels until you can get feet flat on the floor.
- Crawling on hands and knees and then try with knees off the ground, great core work out.
- Activating the diaphragm, hip flexors and glutes in area 1. You do this by by rubbing/massaging up and down lightly on your sternum, breast bone, feeling your skin move as you rub, this is for the diaphragm.
Hip flexors, rub your belly with flat hand just below belly button, then try poking/massage 2 inches out and 2 inches down from belly button and rub those 2 points, again moving skin around.
Glutes, rub/massage at base of skull, top of neck around into side of jaw.
Which may help area 1 to switch on and perform.
These are not the only patterns and causes, bike fit maybe another issue.
Just my musings.....