Tested: Rocket Performance Yamaha YZ250F 6

Once you look past the Geico, Pro Circuit, TLD, and Star Racing bikes in the 250 field, you'll find some of the fastest and yet most obtainable bikes in the world. In this case, that was how Rocket Performance was born, out of a necessity to build engines that could propel a rider to the top level of Supercross and Motocross. The YZ250F presented here, was owner Don Leib's latest bike for his son to compete at some of the biggest events in the country. While Rocket offers multiple levels of performance packages, we'll admit this one isn't for the faint of heart. As the performance is more than 95% of us would ever need, along with a price tag to match. But at the same time, it can allow any pro or top amateur a turn-key package to compete at the highest level of whatever event they lineup at. Oh, did we also mention that this exact bike is for sale? If it's above what you're looking for, hit up Rocket to see what they have to suit your needs and budget.

Rocket Performance - (RocketExhaust.com / 951-471-3500)

Engine surface treatment, Pro con-rod, assemble & balance crank, cylinder head porting, Moldstar valve seats & valve job, valve spring kit, four spec titanium valves, four DLC coated buckets, spec piston kit with DLC wrist pin, Vortex ECU, custom ECU mapping, throttle body stage three mod, wire harness modification, custom billet cam shafts, Rocket Exhaust complete system (race core), and engine labor ($7,511.95).

Lowered sub-frame modification ($150).

Twisted Development - (TD-Racing.com / 951-698-7222)

Second injector kit ($1,049.95).

Manual cam chain tensioner ($139.95).

Aluminum spark plug holder ($49.95).

Hinson Racing - (HinsonRacing.com / 909-946-2942)

Complete clutch with cover ($1,089.99).

ICW - (ICWbikestands.com / 919-795-8084)

Radiator modification ($180.00).

REC MX - (RECMX.com)

Billet oil filter cover ($39.95).

CV4 - (CVproducts.com / 800-874-1223)

Radiator hose kit ($129.99).

Cycra - (CycraRacing.com / 603-298-6646):

Complete powerflow body kit ($257.95).

Full armor skiplate ($89.95).

Faster USA - (FasterUSA.com / 951-600-7048)

Complete wheelset, Faster USA billet hubs with A60 rims ($1,249.95).

RK Excel - (RKExcelAmerica.com / 760-732-3161)

RK 520 MXZ4 Works Chain ($99.63)

MotoSeat - (MotoSeat.com / 951-677-8325):

Custom ribbed seat cover ($59.95).

Split Designs - (SplitDesignsCo.com / 951-695-9998)

Custom graphics kit.

Dunlop Tire - (DunlopMotorcycle.com / 800-845-8378)

MX32 front tire 80/90-21.

MX32 rear tire 110/80-19.

Enzo Racing - (EnzoRacing.com / 714-541-5218)

Re-valve/re-spring forks and shock, Technica spring tubes, and Technica shock adjuster.