Bethany, when you say bruising down there, are you talking about bruising on your ischial tuberosities or farther forward, more toward either side of your vaginal opening? I'm guessing it's the latter. With that information and some of the other things you've said here, it sounds like you're not being supported through your sit bones area. There are a couple of reasons why that could happen. It sounds like you could be sliding forwards on your saddle such that your sit bones are no longer on the wide part of the saddle. Or the saddle could be too narrow at the sit bones area, too pear shaped, have too wide a nose or too dome shaped.
The first thing to do would be to sit on your bike, on your trainer with the bike set to as perfectly level as possible. Try sitting up (no hands) while pedaling lightly and see if you slide forward. If so, you may need to adjust saddle tilt to stop that from happening. Leveling a saddle is a tricky thing because level may not look level depending on the saddle shape. I would try tilting the nose of the saddle up slightly to see if it helps. Do the sit up test again and ride normally as well. If that doesn't work, you're likely getting pushed forward on the saddle by the shape and you may need something with more T-shape to it or a narrower nose.
If you are not sliding forward on the saddle you may be sliding off it because it's too narrow or dome shaped. The best way to check this is with the help of a good friend, and I mean good friend. In your normal riding position you lift your bum up and have a friend put their fingers on the saddle (right and left, one hand for each bum cheek) pads up and sit down on their fingers and lightly pedal. They should be able to give you some feedback about whether or not your sit bones feel like they are being supported by the saddle or if you're wider than the high point of the saddle and are sliding off. The best part of being a female fitter with a medical background is that I can get away with doing this with clients (with permission of course) and no body seems to get weirded out by it.
Cut out or no cut out is another entirely different topic.
I hope that gives you some ideas of things to try.
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2007 Look Dura Ace
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