Race bike essentials

Plastic skid plate is good, prep your bike with the basics (Good lubrication, change your oil regularly, set your controls right etc), bars and race.

MXA says you need one tooth on the rear. Seriously tho, if you're in the weight wheel house get some bars and grips you like and look after your bike. I'm jealous. All my bikes are set for monkey size.

if your asking this question, ill assume u havent raced much if at all, so with that said just keep your bike in good working order, and make a box of spares to bring to the track so a simple fall wont end your day, this is what i always have with me

spare levers
grips
bars
tubes
brake pads
oiled air filter in a bag
rubber gloves
throttle and clutch cables
spark plug


theres tons of other stuff but this is a couple hundred dollars worth of nesesities that you will need sooner or later, make sure your top end is fairly fresh and the clutch is good and ride that thing

YZ250? flywheel weight.
TM

Flywheel weight will broaden the powerband and reduce wheelspin. It will make the bike less barky and easier to ride.

I'd still say suspension. Has it been serviced and revalved to your weight/speed?

I think flywheel weight might be an option depending on your terrain (weight is good for slick/hardpack).

No need to change a filter at the track on race day. They don't get dirty enough in two or even four 15 minute amateur motos to affect performance.

Unless you are in some sort of freakishly rocky area, most motocross racers don't go overboard with exhaust guards.

Keep fresh tires on the bike also. The front might look fresh even when it isn't and it will cost you time.

Spare tubes and plugs are usually good enough for race days.

Keep the bike fresh and up to spec and practice as much as you can!

Wider pegs are a good addition +2 on the fly wheel weight

Old guys sell the FW weight pretty hard. If you're coming off of a 4 stroke or riding slick hardpack then it might be an advantage, but if you're riding in soft dirt or sand you're putting yourself at a mild disadvantage.

The extra weight on the end of the crank also puts more load on your main bearings and will cause premature wear.

I run flywheel weights on all my bikes. It helps "thicken" the power, so when you hit G outs and square edges, the power does not fall off. I find that the flywheel weights do slow the power delivery, but it works to your advantage, as to not light up your tire. This is true on my CR500 and even my RM125. Maybe in Supercross you might want the quicker revs, unless it's hard pack. JMHO from an old fart.

After a year of riding with a 9oz flywheel weight on my YZ, I've come to the conclusion that I love it on everything except sand tracks. It makes the bike really tractable (I dare say 4-stroke-ish), but I'd rather have more snap in the deep sand.

As to your race needs, just keep it simple. I can't really add much to what's already been said, but I'd get a service manual. You can find them online for free, and just save it to your hard drive and print off the pages you need when you need them.