I have a Bosch 2.25hp router and have never had this problem with it. If it won't come out, something is binding. Look closer for scrapes, brinelled material and such. Since you have the same issue with both bases, check the motor body carefully. It won't take much to make it stick. Check the alignment pin for abnormalities and check the grooves in the bases to see if there's any rubbing. A small burr could be all that is wrong.
Lastly, this is unlikely but if you're trying to remove the motor right after you've run it, it could be a heat issue. If the motor housing is warm, it may be binding in the base. You may need to adjust the clamp lever. I assume you are releaseing the clampl lever before removing the motor. ASlso, you have to rotate the motor a bit as you remove it from the base.
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