Weston Beach Race 1997
About the only thing I have pics from... old halide images, scanned and with little post-processing to brighten them up; early 'batch' as I was going through the archive.
Motocross, like most Motorsport is fast and furious. Unlike tarmac racing though, its also MUCKY, and them bikes kick big rooster tales up behind them... be prepared to be 'splattered'!
Also, events tend not to be so 'formal' as tarmac events, the course is usually just a roped off bit of field, with no wide run-off areas or anything, you can often get really up-close and personal, with the subjects.
I wouldn't say that a tele-lens is essential for the sport, in fact the converse; you can get so close and still pack so much in the frame, a wide angle is probably more likely to be used most; that Weston event, is a very long course for an MX... well its not an MX its an enduro... but the back straight is a mile long, and 1/4 mile down the beach! There I did use long tele to get closer to the bikes, maxed-out, as you dont often see them on a short circuit, but for the most part, I was running a 35-70 on a 35mm, or a fishe-eye, to cram the close up drama in the scene.
Think that was cropped from a fish-eye...
PLASTIC BAGS! against the dirt and dust and mud and grim, pack everything in plastic, if not in use, and possibly if it is!
On that beach, some old hands were using old fasioned studio capes, to keep the crud off the camera, and a UV filter just as a 'disposeable' lens protector! I know I spent a week cleaning grit out of my bodies after!
WIPES.. lots of wipes! - if you (and you kit!) ent getting dirty, you ent getting the action!
If its a national or international event...
BUY A PROGRAM, if its an ameteur one, ask the organisers..... just ask some-one in bike gear where 'sign on'is... and ask if you can have an entry list, or results sheet. They club secretarty sends them out a week or so after the event to the competitors; and they are usually quite happy, for you to leave a name and address and the price of a postage stamp to send you one too.... you may even be asked if they can see the pictures!
BUT... I have hundreds upon hundreds of pictures, now, I just have not the foggiest who they are and sometimes even where they are!
Entry list / program can help identify riders in the pics post event, and give your photo's SO much more historical relevence later.
Digital file tagging is a miricle of technology and will tell you the date a pic was taken, even the exposure settings and lens length.... but wont tell you who is in the damn thing, or what they were riding, or how well they did!
Note-book, to jot down racer starts, or a pen to jot it on the program, and link the pics to entry list, and any other event info.... club, venue etc. Invaluable. Especially if the pics get published at some point.
Other than that; much like other action photography; fast shutter to freeze action, but perhaps not too fast, to loose the dynamics. Panning is a great technique, to capture fast moving, brightly coloured motorcycles, and dissociate the back-ground.
And for MX about the only unusuality compared to other motor-sport, is the jumps. Rally cars get air-born, but, not like MX bikes.... six, ten, twelve feet up in the air! Makes for some really dramatic photo's... getting almost right underneath them, you can get some very surreal images with them hanging in mid air, against sky.... so be cautiouse of your exposure compensation... dark bike, bright sky.... and think a little about 'context'... often a slightly wider shot, including some of the course, can make them more dramatic showing how high they are jumping.
And don't forget the landings! Apart from that's where the crashes tend to happen, and that always makes for a picture with.... err..... [irony] impact... its also the tricky part of the riders job.... going up is easy... you point the thing at a ramp, give it a big fist full of gas as you go up it, then hand on for grim death...... it's getting it back down again, that takes the skill, gravity will get you there eventually... its just a matter of where, and when, and how you manage the landing! and a bike flattened on its suspension, the rider, flexed into the bike, at the moment of landing, can be more subtle and impressive than areal acrobatics..... if you can capture facial expressions while they are at it... even better!
Good luck, & look forwards to seeing results.