Thanks very much to both of you for your help.

I tried an psoas stretch, quad stretch plus a hip flexor stretch last night & this morning and I am walking pretty much pain free today - in the sense that the usual 'tug' on my medial knee is much reduced & there's less inflammation. Thighs are a bit warm from the stretches but I guess that'll ease. I went pretty easy.

More info...

When I was fitted for my bike I was assessed for hip flex. Was on my back on a physio bench with knees bent, feet flat. I was then asked one leg at a time to straighten & lower leg over edge of bench. Left (uninjured) leg went to about 180 degrees from body with no sensation of pull but right leg was nowhere near. In fact the pull on the right hip was very uncomfortable & I must have had a deficiency of about 20 degrees compared to left. If I pulled my bent left leg further towards me I was actually raising the right leg just by the tension of the front thigh/hip.

Musculoman - it would be a great help if you could go into a little detail of the steps you would recommend to relieve the tightness & eventually correct the tilt. As mentioned, the psoas stretch has had what seem to be immediate results. I'm finding I need to do these 3-4 times per day, holding stretches for 30 sec.

Also, should I lay off the bike or would you say I should stay away until I see some real & long-term significant benefit from the posture work? I am thinking about reducing the 'lean over angle' on the bike by dropping the seat a few mm, moving it forward & fitting a shorter stem to give the hamstrings an easier ride. I was riding long distances last year on a mountain bike with none of these issues so I'm thinking a move to a less bent posture might help?

Thanks again, much appreciated !!!!