Full Race Spec Pro Circuit 2010 Honda CRF250R – Dirt Rider Magazine

By:

Tuesday, May 18, 2010

Project bikes look shiny and feature all the newest gadgets and gizmos, but often their performance is nowhere near the level it should be and is sometimes worse than stock. Yes, magazine editors and those pushing project bikes upon us ruin perfectly good stock bikes all the time. We constantly want to be original, legitimate and cool with our stories. But our pool of project options is limited to make, model and year of bike and whatever spread of aftermarket parts is carved out of billet and anodized to match.With this in mind Dirt Rider decided to do something newish and a bit more in-depth. We decided to explore the project behind the building of a project bike while finding some settings for riders like you along the way.There are a few things that really get our motors running. Motocross bikes are one of them, sure. But 250F MX bikes in particular are our closest link to perfection on the track, except for a few 125/450 lovers. Why? They just work for most. We can ride them. They don’t scare us. We like saying, “I wish I had more (insert bottom, top or mid here) power.” And it’s always handy to have the built-in excuse-o-meter if your buddies own 450s. What’s the ultimate dream bike? Probably a race-spec 250F with a usable monster motor, trick suspension and the know-how and skill of the world’s most popular race shop behind it. Sound like a project bike? It was. It just wasn’t built yet.We didn’t really know what we were going to build in the end. But we knew what we wanted to build. The key is-and this goes for all our projects-you have to be able to buy it and use it and at least some of it has to make sense for the regular guy. If you can’t buy it, what’s the point in me talking about it? Just then a really good thing happened.About the time this ultimately original idea sprouted, Pro Circuit called and wanted to team up on a task. The job: Dial in its 2010 Honda CRF250R test mule for its customer-based suspension and motor settings. Perfect! We’d be building, testing and developing your future bike mods and building a project bike for others to copy. Sounds like fun.My personal duties: Test ride and provide feedback throughout the developmental process of settings and modifications so the techs and teams behind the PC Racing brand have another set of data to use when setting up your suspension and motor. Also, this would make a great excuse to race a real race bike at the MTA World Vet Nationals. I gladly jumped on board and we went to work on one hot, windy day at Glen Helen (www.glenhelen.com).It’s important to point out that I did not develop Pro Circuit’s suspension modification settings or the motor mods it’ll use throughout the year. More so, I was a guinea pig it could try stuff on. It has a multitude of test riders it uses and the dyno in the back of PC’s shop is its number one motor building tool. I simply rode its options, offered educated opinions and went along for a great ride.

Stage One

At this point in the game, our 2010 250F Shootout (April ’10) was all but wrapped up. I had ridden the CRF250R often so I had a feel for the stock bike’s settings. Day one’s roll call at the track included Pro Circuit’s Jim “Bones” Bacon; PC Racing technicians Damon Conkright and Brad Benesch; Pro Circuit test rider, Competitive Edge track operator and former professional racer Joe Oehloff; and myself.Pro Circuit starts testing at noon, when many hyperactive moto maniacs at Glen Helen have lapped their way into exhaustion. Sounds lazy, doesn’t it? It’s not. Pro Circuit likes it rough and mean and hot and nasty. We showed up early and did a few laps on our stock bike. I personally didn’t want to be “that magazine guy” that rides two laps, changes something, rides two laps and then goes home. I wanted to be a PC test rider and I tried my hardest. But these guys are tough!Test days consist mostly of riders doing laps. As we do laps we download what the bike is doing. We feel things, we try to hit the same bumps over and over, we try to hit new bumps, we try to miss bumps and riders like me fall over at least once. I’m glad Mitch Payton wasn’t there.After a ride session, test riders sit down and upload information into Bones’ databank-which is mostly in his head. All of us on staff have been involved in different test situations, whether it be with the staff here at Dirt Rider, with other manufacturers or project bike builders and even the non-formal friends-at-the-track deal. Not everyone does it the same or, often, very well. Most tend to contaminate the minds of those “testing” by suggesting things or asking leading questions like, “How good is the top-end power now?” A question like that makes a test rider think about nothing but the top-end power and they automatically think it’s good. It’s better to listen than to lead.Bones does it right. He says little and lets the bike tell its story through his test riders. He sort of just looks at you and then you tell him something. When he talks he says, “OK, I want to try something. You tell me if it’s better or worse and what you think it’s doing.” And just like that a new shock and fork combination went on the bike and we were off again. I have no idea if my opinion was “correct.” I just knew the bike was now doing something differently and I should remember what it is. Blind test sessions like these are truly valuable to a setup guy like Bones and it’s no wonder a top-notch shop like Pro Circuit uses them. It went on like this for hours.During our first stage of testing, we picked a shock and a fork combo. We discovered a flat spot in the power delivery that turned out to be clearly visible in the dyno chart and experimented with different gearing to get as much of the power in the sweet spot for Glen Helen’s gigantic uphills. I was going to be racing against 450s soon and I didn’t want to have the smallest knife at the gunfight.Motor mods were simple. The higher-compression piston felt a bit stronger off idle but the overall power character of the bike was a mirror of stock. Since we were using stock cams and stock porting, this isn’t a big surprise. There was more over-rev pull and the full exhaust system seemed to enhance this further. We were really hoping for more bottom-end power from the Honda CRF250R. Stock, the bike is smooth on bottom and lacks the punch of other bikes. In a full-traction situation, more excitement out of the motor to get in the mix sooner would be nice. However, Glen Helen was set up fast and straight (sometimes straight up!), so I felt confident going into the race weekend that the bike would hold it’s own. Let it rev and feel it pull.The bike did just that. The motor pulled hard on top. It got excellent starts thanks to the long straight before Talledega and some inside gate picks. Plus, I could ride this bike forever. I wanted longer motos so I could use my extra energy to make up for their horsepower.Part of this perceived increase in endurance is credited to the suspension work PC did and our testing days at the track. The setup had a dead feel initially and would move throughout the stroke-even into Glen Helen’s huge race bumps-without ever feeling harsh. The bottoming resistance was there, too, and those deep chuckholes with square edges tested it plenty. As the track broke down, I opened up the rebound on my rear shock to get the rear tire to follow the ground better on acceleration but left clickers alone for the most part. After all, when it gets as rough as Glen Helen got that day, there’s only so much you can do with a screwdriver.More impressive still was the stability. Pro Circuit’s linkage arms drop the rear of the CRF a tad. They kick it back just enough to make it straight-line stable without losing the wonderfully direct front-end feel. During testing we altered the fork height a few times to find a good balance and settled on having them almost as low in the clamps as possible. There is some compromise, sure. But at Glen Helen, we were happy to trade a bit of ultra-responsive steering for some confidence at speed. The corners were, for the most part, wide and soft so a more “settled” bike went through them well. During practice before the race I blindly tested two PC custom-valved Honda steering dampers Bones had given me but felt best with the stock unit set 2-3 clicks stiffer for the high-speed course.

Stage Two

It might sound strange but the term “hurry up and wait” is very true in motocross. You hurry to the track and wait for practice. You hurry to the line and wait for the water truck. You hurry to eat your breakfast burrito and wait in the porta potty. It’s a lifestyle we choose and love.For this story we quickly found ourselves in a holding pattern. While the Pro Circuit testing crew likely had more time on a modified CRF250R than most, we couldn’t really do much for the second half of this story until we got some race cams and other parts. The Vet race was in November 2009. Yes, November. So we had a good head start. As I write this it’s late January 2010 and we just finished testing and prepping the bike for its last photo shoot with the Ruiz brothers.Since there was this Holiday-sized gap between testing sessions, we came up with a cool way to take the next step. We’d obviously have to retest the bike in Stage One again. After all, it’s been two months. But we didn’t want to wait a day to test the full race motor in comparison. We wanted a back-to-back evaluation. So Bones and Benesch offered to convert our CRF from Stage One to Stage Two at the track. Awesome! Now we had the weather to deal with.Glen Helen, our original testing ground, was unavailable when the day came. A winter storm was coming and directly in front of it were 80 mph winds making San Bernardino a dust bowl. We settled in nicely at Milestone MX Park (www.milestonemx.com) and parked the boxvan into the wind so the makeshift shop in the back would be somewhat sheltered. Again, we met at noon. And just before dark this story was finished.Stage Two included some serious hardware. But before we get to the goodies let’s be reminded of how important setup and testing for specific tracks is. For most of us in the real world, we can adjust a clicker and get something to work at our local sand track vs. our local hardpack track and we should know well enough to check our sag to stay in the ballpark of a good setting. But when taking a bike meticulously set up for Glen Helen’s fast hills and open straights and plopping it into Milestone’s jump-infested rut world, making it work is…well, work.Immediately we needed more bite in the front end. We raised the fork tubes 5mm in the clamps and that helped a ton. Then Bones opened up the fork rebound. This puts less damping on the rebound stroke and lets the suspension “load” the front tire more as it comes out of the compression stroke. It worked. Track conditions were loose with a firm base and most agreed that a Dunlop Geomax MX51 front would bite the hardpack a little better but the Bridgestone 403 wasn’t awful. Just like that we converted the Glen Helen bike into a Milestone bike. It was great. Not perfect but really, really great. I backed the stock steering damper off a few clicks (since the track was slower) right before they tore the motor apart.This was the coolest part of my three-month testing experience with Pro Circuit. Benesch replaced a cylinder head in 25-30 minutes. In the back of a boxvan. At the track.Those scared of four-stroke top ends should relax a bit according to Brad. “It’s all pretty straightforward. Shimming valve clearances is sort of a pain but there is no guesswork. Same with dropping in a cam: Line everything up and you’re good to go. Not doing the work is where people get in trouble,” he said as he calmly installed a $1900 cylinder head as a windstorm shook his temporary garage.From here there was a distinct transformation in our little CRF. Gone was the flat spot in the power and the bonus bottom-end torque was even more alive. But right smack in the mid was the most impressive change. Here, the red bike just lit up. It wasn’t only strong; it felt exponentially stronger the more you pushed it. In full race-spec it has a bump in power that is just perfect for a fast guy looking to squirt past someone on a straight or a lazy vet wanting some pick up. The motor sang on top, too, with a pull in line to stock but at a whole new, stronger level. This is pro territory. If you came into a corner at pro speed, feathered the clutch and kept it wound up, this bike would make anyone feel like a hero. But, it wasn’t just for guys who can do that fantasy rider stuff.The bike was 100 percent as easy to ride as stock. And that’s the true beauty here. Anyone could get on this bike in full race-spec and enjoy the ride. It’s like a mini 450 without any of the scariness. I’ve ridden mild big-bores that were wimps compared to this. Having EFI controlling that power delivery was even better. I couldn’t stop riding it (not that Bones would really let me stop riding it anyway). Every time I came in for a break, he’d ask me to go out again and do a few more laps so he could see what I thought this time.The motor continued to feel great all afternoon. It sounded great, too, without too much bark but just enough grunt. It was a serious race bike for real racers with skill above mine by about five or six degrees. Our suspension settings were working as the bike was often over-jumped and randomly missed lines due to the increased speed. But after getting used to it, it was money. It felt like a bike that had come from a serious race shop. It was the ultimate 250F MX bike and it was all ours, for a day. I felt like a satisfied customer.Just as we were about to call it a day I pulled in and chatted with the guys again. That’s when Bones pulled out two steering dampers and said to me, “I want to see what you think of these.” So we started all over again. Stock, modified number one, modified number two, back to number one, back to number two and back to stock. I was tired but in another hour or so of testing I found out that I like steering dampers that only valve back to center better than ones that only valve away from center or even ones that valve both ways (stock).That last sentence wraps up the pro testing mindset. It sounds confusing and overwhelming. But it isn’t, really. As we found out during my stint with the Pro Circuit squad, it takes a lot of these comparisons-sometimes of the smallest nature-to come up with a baseline setting for the “world” of motocross. Sure, our input into Bones’ upstairs database is probably a relatively small drop in the bucket. And I’d certainly be delusional to say I developed your Pro Circuit suspension settings because my name’s on this story. But in the end, I’m a user just like you, and I got there first, so feel free to copy “my” bike settings. There are little parts of them in all of Pro Circuit’s settings.

Parts List

When you look at the price lists for this bike reality, for a lot of you, will fly out the window. Because this bike is $6000 more expensive than a stock bike I don’t blame common sense for kicking in. However, for the money, you’re getting value across the board. This motor isn’t a factory race bike that needs to be torn down every two hours. The piston has a standard 20-hour lifespan and the valves’ clearances need to be kept in spec like a regular motor but you need to check them more often. You don’t even need to run race fuel, but dropping some VP race fuel in the tank makes it run best. Suspension components are built for your size and style and a good shop like PC will listen to your requests, look back at their data, and build it up. So, if the big-budget build is out of whack for you but you still want a more customized race bike, picking and choosing the few areas you want improvement from-and asking PC to dial those in-will be money well spent. After all, we built this bike piece-by-piece and every step worked.

STAGE ONE MODS:
TI-4R Race System (closed-course competition) exhaust $999.95
Pro Circuit graphics Kit w/seat cover $164.95
Clutch cover $169.95
Engine plug kit $109.95
Flow-thru footpegs, stainless $109.95
Titanium valves (exhaust) $349.95
Titanium valves (intake) $349.95
High-compression piston $274.95
Clutch springs $69.95
Triple clamp-bottom clamp $299.95
Triple clamp-top clamp $199.95
Bar mount $99.95
Linkage arm $224.95
Fork revalve and setup $179.95
Fork internals $169.80
Shock revalve and setup $149.95
Shock internals $50.85
Fork springs $129.95
Shock spring (standard) $129.95
Bladder cap kit $58.85
Anodized kit (shock) $119.95
MX National spring tubes $349.95
Total Stage One mods: $4,563.55
STAGE TWO MODS:
Camshaft $522.95
Valve springs $164.95
Steering stabilizer revalve $99.95
Head modification $549.95
Total Stage Two mods: $1,337.80
Total mods: $5,901.35
Follow Us:
Subscribe
Dirt Rider Magazine