Is the 100-400L good for action shots?

Some pics here - http://pbase.com/sjh
20 D; 85 1.8; 24-70 L; 70-200 f4L (sold); 100-400 L; 420 Light bulb
1550 Pelican "soft case" & too much junk!!!

I use the 100-400 almost exclusively for Motocross and dragracing. I love this lens. For what I do the 70-200 is not long enough and adding a 1.4X tele is out of the question...

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Jeff
CANON * EOS 1D MKIV * EOS 1D MKII *
* 100-400L IS, 300 f4L IS, 70-200 f2.8L IS, 24-70 f2.8L, 50 1.8 and alot of other gear.
JT Photographics

Louisiana Flavors @ http://community.websh​ots.com/user/torretab

Canon 30D & Grip+E1 \ 50 f1.4 \ 17-40 f4.0 L \ 24-105 f4.0 L IS \ 100-400 f4.5-5.6 L IS \ 500D Close up lens \ Speedlite 420EX \ Kenko 1.5 TC \ Kenko Ext. Tubes \ Gitzo 1325 CF Tripod \ RRS BH-55 RL Ball Head \ Manfrotto 679B Monopod & folding tripod base \ RRS BH-25 RL Ball Head \ 10Gb of Lexar CF Cards \ Associated "little extras" \ Lowepro Mini Trekker AW & AW75 Toploader \ LUCK!