Flipped Around – TWMX Builds Nate Adams Ultimate Moto Machine: The 2004 Pro Circuit/Factory Connection Yamaha YZ250

:: By The Testing Staff Of Transworld Motocross ::

We have to be honest with you. Project bikes are a lot of fun! And as magazine editors we get to enjoy the process from every aspect. From conceptualizing the end result, working with our industry’s top hop-up shops, all the way to seeing the looks on our test riders’ faces after their first few laps on a fire-breathing new steed, turning a stocker into a modified maniac is a hell of a good time. This project was no exception. In fact, for our 2004 YZ250 we added yet another cool element to the process that made the job even more meaningful: gold-medal winning professional freestyler, Nate Adams.

No, we weren’t interested to see how well our Pro Circuit/Factory Connection YZ250 could backflip. Nate’s a motocrosser at heart and was stoked for the opportunity to join us at the track for a couple days of testing. “I was talking to Garth and thought it would be funny to run a moto shot of me in the magazine. I’ve always wanted to make it into a magazine for motocross because that’s where my roots are, but everything I do now is for freestyle. Garth called me up to let me know that a Pro Circuit/Factory Connection YZ250 was in the works, and I was all over it!” It wasn’t until 2000 that Nate tried his hand at freestyle. Little did he know at that time that an innocent invite to a contest would lead him into the role of one of the world’s best freestyle riders. Prior to that event, Nate was an up-and-coming motocross intermediate with goals of some day becoming a professional Supercross star. From that point forward his freestyle career blew up and Nate quickly became too busy to keep racing. “I often wonder what could have been had I stuck to racing, but I know that if it wasn’t for freestyle I could not have moved out here to California, and definitely could not afford the lifestyle I am leading. Now I have the resources to continue doing freestyle as a career, but I can also ride motocross and participate in some races here and there as well.” With a bit of time off from his demanding freestyle schedule, Nate and his brother loaded up his van and headed to Lake Whitney this year for the amateur National. Nate took home a 17th in the college boy intermediate main event. Not too shabby for a freestyler!

TRICKED OUT

With Nate’s only real restriction being that he can’t mount anything other than a Yamaha…well…at least motorcycle related, we pulled our bone-stock YZ250 from the stable and recruited Pro Circuit and Factory Connection for a little TLC. When the motor was returned from Pro Circuit we expected only minor refinements. After all, the 2004 YZ250 comes stock with what is arguably one of the best 250cc two-stroke motors ever. Its power delivery is crisp, smooth, powerful, and extremely predictable. Where could they possibly improve this thing without sacrificing somewhere else in the powerband? We’ll get to that later…

As for the suspension, we decided to see what Factory Connection could do with our Yamaha’s Kayaba set-up. FC’s Showa mods to the traditionally stable and well-balanced Hondas have always been delightful, but their Kayaba capabilities are relatively unknown to us. The only real complaint heard about the 2004 YZ250 during our shootout a few months ago was with its rear-end handling. The new 48mm front forks work great, but riders complained that the rear-end felt harsh and almost lazy at times under certain conditions. Could FC remedy the problem? We’ll get to that too…

RAMPLESS

We hit the track for two full days of riding with Nate. The first came before our Factory Connection suspension mods had been completed, and the second came post-modifications. We decided that this would prove to be a benefit as it would give Nate the opportunity to experience the bike’s handling in stock form before critiquing the FC mods. It had been a long time since Nate’s last ride on a 250 on a motocross track, so we couldn’t help but wonder how he’d adapt to r moto set-up. As you’d imagine, our local test tracks don’t feature too many super-kicker freestyle ramps, so the need for chopped seats and suspension stiffer than titanium rods is simply not there. “Motocross bikes obviously feel different than my freestyle bikes do,” said Nate, “but it’s one of those mind over matter things. I know I am about to moto so I know when I go to sit on the bike that it’s not going to feel like my freestyle bike. Those things are set up with really stiff suspension, and my seats are cut down for maneuverability. Riding one on a moto track is a death wish!”

During the first day of testing a couple of things unfolded. One was the realization that Pro Circuit had somehow figured out a way to make a great motor even greater, and the second was Nate experiencing what it’s like when one of the roughest motocross tracks in SoCal progresses from early morning buttery smooth glory to late afternoon stock suspension hell. Enter day two, and our findings…

After the installation of our new FC suspension, Nate and a few of our regular testers rolled back out for a day in the dirt. We all knew from the first day that the PC motor was just about flawless, so handling was the thing on everybody’s mind. “The first day of testing on the stock suspension felt okay to me, but I didn’t have much to compare it with. It wasn’t until the Factory Connection stuff went on that I realized what we were dealing with,” said Nate. “I noticed that on the long rough uphills that the Factory Connection stuff tracks way better. The back end stays squatted more, which allows for smoother acceleration up the hills, and obviously allows you to get up the hills much faster as well.” For every uphill we climbed there was a downhill to descend, and as braking chop began to get bigger toward the bottoms of the hills, the Factory Connection set-up helped to cure a characteristic of the stock rear-end that every test rider agreed to be present, including Nate. “I noticed that with the stock stuff the rear end would start to load up over the course of three to four bumps and then it would bottom out and spring up, sending the back end up in the air. With the Factory Connection stuff it soaked it up a lot better. It wouldn’t load up and kick. It stayed smooth and straight.” As a result of what was described by many as a settling sensation, exiting rutted corners is also vastly improved with the FC modifications. “The rear end stayed seated a lot better out of the corners where acceleration bumps were present. All in all it tracked better and stayed straighter, which allowed for harder acceleration.”

Now… Back to the motor. As previously mentioned, the 2004 YZ250 boasts an impressive powerplant in stock form, as our boy Nate explains. “I ran a stock motor on my Yamahas this year. I was planning to get motor work done because last year Pro Circuit did the motors on my Hondas. My Yamahas, however, are faster in stock form than my Hondas were, even with motor work!” After the first day of testing it was evident that the Pro Circuit mods did nothing but improve an already great package. When coupled on day two with the new-and-improved suspension, the extra ponies hooked up even better, leaving quite an impression on every tester. “The Pro Circuit motor pulls way harder and longer in each gear, and it feels very electric when you roll it on, especially out of corners,” said Nate. “You just roll on the throttle and it keeps pulling harder and harder all the way up the hills.” The PC motor has a very electric feel to it and it has no weird quirks in the powerband. There’s a good strong hit off the bottom, but it’s not more than can be handled, and it continues to pull hard through the top end with each and every gear. We can honestly say that this is one of the strongest, most rider-friendly modified motors we’ve ever tested.

Other than some minor adjustments to the suspension damping settings to better suit each individual rider, every test rider agreed that the Pro Circuit/Factory Connection set-up is a great pairing. “I’d possibly fiddle with the compression clickers to fine-tune the suspension for me, but other than that, this thing’s ready to race. I would definitely run this set-up—It’s a blast,” said Nate. While we don’t think Nate’s going to give up his freestyle gig anytime in the near future, we do expect to see a lot more of the speedy MXer at our local moto tracks real soon, thanks to our inspiring new ride.

PARTS IS PARTS
MOTOR
Pro Circuit cylinder & head modification $329.95
Alter transfer ports
Polish exhaust ports
Match power valves
Machine head to tighten squish band
Change compression
Match cases to remove casting flaws $99.95
Split cases clean & inspect $299.95
Surface center cases to prevent air leaks
Pro Circuit Works Pipe $199.95
Pro Circuit Factory Sound Shorty Silencer $112.95
SUSPENSION
Factory Connection shock revalve $170
Factory Connection fork revalve $170
Factory Connection fluids $30
Factory Connection special parts $46
CONTACTS
PRO CIRCUIT
909/738-8050 www.procircuit.com
FACTORY CONNECTION
800/221-7560 www.factoryconnection.com
every test rider agreed that the Pro Circuit/Factory Connection set-up is a great pairing. “I’d possibly fiddle with the compression clickers to fine-tune the suspension for me, but other than that, this thing’s ready to race. I would definitely run this set-up—It’s a blast,” said Nate. While we don’t think Nate’s going to give up his freestyle gig anytime in the near future, we do expect to see a lot more of the speedy MXer at our local moto tracks real soon, thanks to our inspiring new ride.

PARTS IS PARTS
MOTOR
Pro Circuit cylinder & head modification $329.95
Alter transfer ports
Polish exhaust ports
Match power valves
Machine head to tighten squish band
Change compression
Match cases to remove casting flaws $99.95
Split cases clean & inspect $299.95
Surface center cases to prevent air leaks
Pro Circuit Works Pipe $199.95
Pro Circuit Factory Sound Shorty Silencer $112.95
SUSPENSION
Factory Connection shock revalve $170
Factory Connection fork revalve $170
Factory Connection fluids $30
Factory Connection special parts $46
CONTACTS
PRO CIRCUIT
909/738-8050 www.procircuit.com
FACTORY CONNECTION
800/221-7560 www.factoryconnection.com