In order to install the flywheel weight, Steahly laid the bike on its side and propped up the rear tire. The main reason for this is so the oil doesn't need to be drained.
The Honda CRF450R has become the
high performance 4-stroke to own for competition-minded individuals. Heck, even those that don't race have come to sing the praises of Honda's big-bore machine over the last few years, lauding its stellar engine performance and superb handling.
In 2004, the CRF was revamped to make harder hitting power for the motocross track, but that hurt its power delivery for the more subtle environment of woods riding. In addition to a redesigned piston, altered ignition timing and a lighter ACG, Big Red also shaved 130 grams from the flywheel for lightning-quick revs. That's great for the racetrack, but in the woods that snap can become a nuisance. Adding weight to a flywheel is an old stand-by technique to make a hi-po Thumper's power a little more manageable.
MCUSA's Lead Programmer, Joe Wallace, recently purchased an '04 CRF450R, and although he loved the potency of the 449cc four-stroke, he quickly realized that it would be easier to ride through the tight wooded trails of Southern Oregon if his bike didn't have such a abrupt snap off the start. After hearing rave reviews from a friend about adding a flywheel weight to his bike, Wallace decided to give it a try and see if it would help tame his beastly 450.
Size diffrence new vs. stock
Adding weight to the flywheel dampens some of the initial power that the engine produces. A flywheel is similar to a merry-go-round at a playground. When there is no one on the merry-go-round, you can quickly spin it from a standstill, and abruptly stop it with virtually no effort. Now if you put 300-pound Joe Schmo on the contraption, it takes more effort to get the thing spinning. Added flywheel weight slows the acceleration process, smoothing out power delivery to make it more manageable.
Wallace's only concern about adding the flywheel weight was that he didn't want his bike to lose its hit on the track. After a quick conversation with Chuck Steahly, of Steahly Off Road
, they decided that they could reach a compromise by adding a mid-sized flywheel weight; a 13-ouncer out of the available 9, 11, 13, 15, and 17-ounce options.
In order to install the flywheel weight, Steahly laid the bike its side and propped up the rear tire. The main reason for this is so the oil doesn't need to be drained. Next, he removed the shifter and engine case cover, which exposed the flywheel. There is an oil hole at the end of the crank, and damaging it can cause major engine problems, so it's important that a specially made puller is used when removing the flywheel. After the weight is added, the flywheel is put back in, and the nut is torqued down to the correct specifications. With installation complete, playtime could officially start.
"From the first ride I could tell that the engine could be bogged down substantially more than it could in stock form," Wallace said. "In tight wooded sections, you could just leave it in second gear and motor along. But when you needed it, the power was still there and still hits just as hard as it did with the lighter flywheel."
Bottom Line: A heavier Steahly Off Road flywheel is the perfect cure if you're looking to smooth out the power on your CRF450R, or for that matter any other bike that you would like to make a little more user-friendly. The $150 cost is well worth it.
Visit Steahly Off Road for a full line of aftermarket parts at www.steahlyoffroad.com