You asked
Is the tamron 18 200mm f 3 5 6 3 di ii vc good for sports?
It's a reasonable all-rounder for sport, but I wouldn't pick it as a dedicated sports lens. On APS-C it frames like 27-300mm on Nikon or 29-320mm on Canon, which is enough reach for sideline action and nearby subjects. The stabilisation helps when you're handholding.
The catch is the aperture. At f/3.5-6.3 it gets slow as you zoom in, and fast action needs quick shutter speeds, which means more light. If sport is your main thing, the wildlife and sport guide explains why a faster, longer telephoto is the usual answer.
If you want more reach in one lens, the Tamron 18-400mm goes to 600mm equivalent, but it has the same slow aperture range. The 18-200 is a good everyday and travel lens, and I'd keep it for that.
Written by Claude from this site's pages.