You're son sounds a lot like me. I have dyslexia, ADHD, fine motor skill issues, and other various 'specific learning disabilities'. I'm also billingual (french and english). I'm 16 by the way.
People thaught I was a good reader untill 6th grade. I was the only one in my preschool/kindergaten class that could 'read'. What I had actualy done is memorized about 15 Dr. Seuss books and a few of my other favorites. I have an exceptional memorie (as long as I do not have to memorizing a series of letters and there 'meaning'). People would read me the book once, then I would 'read' it back to them. If I should forget, I would use the pictures to remind me. In first grade I went to a french (I live in a french speaking area of Canada) school, and we did not take english untill the third grade. I was behind in reading/writing but the school figuired that was because I also spoke english, and was confused with my two languages. When we did start english, I was the only one who had taken english in prop grade, so I was ahead. In grade 5/6, once they took the pictures out of books, and they were so long that they couldn't be easily memorized, my grade plumeted, and I was assesed and diagnosed as dyslexic.
I have never been a good speller, ever. But before my assesment, since I could 'read' it was thaught that I was just lazy. My hand writing is completely illedgible, even now it looks like a four year old wrote it. I tell people I have a 'cutting impairment' because I can't cut a straight line, just a jagged, out of control line. When I write, I have a tendancy to mix up letters, leave them out, or add them. I was that one kid who flunked inventive spelling. My writing is usualy poorly organized. I've been told it looks like someone took all my sentances, chwed them up, and spit them back out onto my page. The same has been said for my spelling. With the shoe tying, that's why they inveted velcro, slip ons,and laced tied loose enough that they can be slip ons.
But, like your son, I also have many talents skills. I am very social and articulate (I kick but at public speaking, the only part of language arts that I enjoy). I am good at drawing/painting and I can play 8 instruments. I swmi competitivley, and I do ballet, jazz and tap. I play Lacrosse and field hockey. And no, that many sports is not excessive. When one has ADHD, one must be very active, or one finds it hard to sit for whole classe. You son will discover what he excels at.
Getting an assesment in a very good idea. Don't leave it until he's in grade 6 and still misspells his own name. Don't let teachers put him down, or call him lazy. Don't let him believe people who do call him stupid, lazy, slow, unintlligent etc. Good luck!