I rode my road bike 2.5wks ago, noticed pain in left cheek almost instantly. Kept riding thinking i just needed to get use to the saddle again. Pain got worse, had to keep standing(real sharp pain when lifting off seat) Rode several hours and was really hurting when done. Took tri bike last 4 rides, pain is not bad until i get out of aero bars then its like it was on road bike. Feels like something is swollen or inflamed right at base of left sit bone, can feel knot. Anyone ever had or heard of this? Thanks for any replies.
piriformis?
Thanks for quick reply but im not feeling anything in leg, just 1 spot right at bone,
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Look up Ischial Bursitis, or some thing close to that spelling, and see if that fits your problem. As a last resort, you could always see an MD 
Good luck