First off, get a life.. \\; Second I know several disabled people that can not ride 2 wheels so 3 have to do. \\;
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I saw the triglide and it is SICK!!!
Here's another link \\;with some pretty good photos. I know that with the condition my Dad's knees \\;are in that \\;he probably couldn't handle a 2 wheeled Ultra for too long. IMO this would be a great option of him.
Been riding scoots since 1962 and still on 2 (so far) but will be on 3 if that's what it takes. \\; Love it that MoCo will help make sure that I can and at a decent price too.