2007 Yamaha WR250F - Dirt Rider Magazine

You read about the WR's stellar performance in the DR 24-Hour (May '07), and since it's been inducted into our Long Haul fleet (July '07), the blue bike keeps on giving. One 24-Hour wasn't enough, so we gave it another...and another! Just the following week we brought the bike to our sister publication's (ATV Rider) 24-hour event and rode the bike most of the time, including hooking up some of the lights for our light buyer's guide (August '07). The WR has a good charging system stock, but we wanted to run even bigger lights. Upon getting the bike back at the shop, we installed a Baja Designs modification to unify the power output of the stator. The mod took a couple of hours and sends all of the juice to the battery so you can run a lot of light, if the need arises. The kit includes a bigger voltage regulator and all the plugs fit together less one locking clip, which later on, fooled with us.Next stop was the Coalinga National enduro, where Chris Denison lined up in the 250B Class and piloted the Yamaha over 70-plus miles of mud and gunk. "The WR was perfect for the nasty conditions," Chris commented. "It's ridable in tight trails, nimble in the mud and, above all, it's got a button start!" During the race Chris, along with about 330 others, eventually houred out but he ended up sixth in the class without doing any damage to the bike beyond a thick layer of asbestos-laced mud.We did have an issue when changing the oil, though-we tore the vent right off the oil tank. Lesson learned: Don't torque the bolt too much and a little anti-seize would've helped.Next was a 30-hour-plus stint on some of our favorite trails alongside our Husaberg, racking up the hours. Here's where the bike started to run funny. It was like it was running out of gas, but why was the battery was going dead, too? We checked the fuel supply which was OK, then looked into the battery, which had been dead when the bike returned from the enduro. We thought the headlight switch was accidentally left on as the battery took a full charge and was fine. It died again just three hours later. We suspected the soldering job I'd done on the stator was the culprit and tore into the motor, but the stator checked out. Remember the plug without the locking clip? Well, we should've checked that first as it had pulled apart and stopped the battery from charging. The bike was running off battery power. The Baja Designs instructions clearly said to tape and secure the wire, which we did, but not good enough. Once the problem was identified, we took the extra measure of wiring the connection shut; it was off and running without even a hiccup, and the bike even charged up its own battery!After an oil change, valve clearance check (everything was in spec), a clean air filter and a set of new Maxxis tires, we sent the bike off to the Six Hours of Glen Helen to run the Ironman Class-it pulled off a second place. The soft suspension was the biggest issue, so we had K5 Suspension (818.261.8518; www.k5suspension.com) do a service where it stiffened the final third of the shock stroke and added oil to the fork to add bottoming resistance and progression to the stroke.

We pushed on with the torture with another 30-hour-plus stint out in the desert. We thought we'd see how the bike would like wide-open running, nearly 1200 miles of it by the time we were through. We laid out a 55-mile loop that took just over an hour to ride, and the only change to the bike was a bump in the gearing with a one-tooth-larger countershaft sprocket. The bike was pinned for most of the time, and all we did was one oil change halfway through the night. At the end of it we thought that the bike would feel at least a little bit tired. We were wrong. It was still running as good as if not better than when we first got it. Just to be sure, we took it by Yamaha where it ran it on the same dyno it uses to break in the bikes. The technicians have a record of this very bike, and after 125 hours on the run timer it had only lost 0.5 horsepower compared to when it was fresh pumping out 31.9 horsepower. Not bad considering we felt we were abusing it. The valves still checked out in spec and everything looked brand-new on the inside. The outside was another story.From here on out we sent the bike out on every trail ride we could get it invited on. Everything from family putt-putts to hard-core EnduroCross training. It survived everything we could throw at it, and the only casualties were the radiators which were bent so bad it was too late for help in the form of a guard. We even had to have the tabs for the shrouds welded back on.Our last hurrah for the bike was a final 24-hour at Glen Helen. We passed the bike to Tyler Ruiz and his team of riders, who easily finished the event though they had a clutch abuser on the team, going through one and finishing on another nearly smoked clutch.With 202 hours showing on the hourmeter (and we know it wasn't working for a few hours as well), we took the bike to the photo studio and tore into it. Aside from a lot of bumps and bruises, like a smashed oil tank, an insert in the gas tank in which the shroud bolt had become stuck and lower frame rails that looked like they'd been dragged down a gravel road, everything was tight. The motor was in shipshape except for the cavity where the oil pickup resides, and it showed that something metal had gone though the motor. We'd never noticed anything in riding it or in changing the oil and the oil filter, but the pickup screen had been doing its job. There were no signs of damage anyplace else in the engine, and we imagine it was a piece of the clutch damping system or some debris from one of the clutch changes. The piston looked like it could go another 200 hours and every bearing surface inspected was perfect. The cylinder did show some wear but checked in spec with the ring end gap still having 0.004 inch before it went out of the published (conservative) range. The valves hardly showed any signs of wear, and the fact that they never needed any adjustments would back that up. We had this bike on a diet of Yamalube 20W-50 and running Rock Oil SWAFF on the air filter. If this is the result, we recommend this stuff. Again, it's a testament to keeping the air filter clean and installed properly with fresh engine oil.Running Tally
Hours on Bike: 202+
Maintenance and Repairs: $634.64 (notincluding tires)
Fork service: $85
Fork seals: $20
Shock service: $95
Valving: $55
Shock oil: $15
Weld radiator: $15
4 oil changes and 1 filter
Oil filter: $11.95
Yamaha 20W-50 oil: $4.88 ea.
Oil tank: $183.94
Clutch: $162