2008 Yamaha YFZ250

Although it sure does look like it, this particular YFZ250 isn’t actually available at your local Yamaha dealer. At this time Yamaha has yet to produce or even comment about producing such a machine, but once we got the word that SRF Racing’s Theo Lusardi was building one for his son to race in the 91-300cc 2&4 Stroke 12-15 class at the ITP QuadCross Series we just had to learn more about this crafty project.

The Engine
The project was underway when Theo ended up the winning bidder on a 2001 Yamaha YZ250F engine on Ebay. While the motor was being shipped to his home in Southern California, Theo hit the drawing board and began dissecting his 2006 Yamaha YFZ450. As soon as the 250 powerplant arrived it was put into the YFZ frame for measurement. The first thing Theo did was insert the swingarm bolt through his new motor and the YFZ frame. That would tell the whole tale. And according to Theo the story wound up being a good one.

With the swingarm bolt dictating where everything needed to go, he then created the quad’s new lower mounts. After that the front and upper engine mounts were sculpted out of some scrap chromolly.

Next on the to-do-list was to change the angle of the water pump outlet and the water outlet on the engine head in order to provide enough clearance for the stock YZ250F header pipe. Once this was complete all the hoses, including those that lead to the PWR YFZ450 radiator, were matched up with optimum flow. As we said, the stock 250 header was used but not without a little tweaking. A stainless tubing sleeve was fitted to the header pipe in order to make it fit into the Dr.D tail pipe that SRF Racing had nearby.

 

The Chassis
Although he would have liked to use a 2006 YFZ swingarm to shed a couple more pounds from the machine, Theo ended up hand-making a swing arm to mate to the 250F powerplant and YFZ450 rear suspension. A few minor adjustments later and the chassis portion of the project was finished.

The Finished Product
With it all together and a half a tank of fuel in its belly it was time for the weigh in. The front is three pounds lighter than the rear and altogether the quad is a whopping 100 pounds less than a 450 race quad! Needless to say, Theo was extremely impressed and couldn’t wait to see how his new YFZ250 performed on the track.

There’s no sugarcoating it, the little 250 does lack in the torque department, but even without the 200cc difference, it really isn’t that much slower than its 450 big brother. In fact, since it’s 100 pounds lighter, Theo doesn’t think there’s much disadvantage at all. The machine is nimble and effortless to throw around. “I love it!”, says Theo’s son, Kevin Speer. “The 250 is so much better than a Blaster. I think I can run with 450’s and 250Rs with this quad. I just wish the manufacturers would make a production quad like this.”

After winning its first race, the novice class at the White Brothers Four Stroke Nationals, the little YFZ impressed quite a few people, especially since all the other entries were 450cc machines. At the next race, round three of the ITP QuadCross Series in Taft, CA, Kevin got his chance to race the quad when he entered the the 91-300cc 12-15 class. He and his sharp-looking 250 impressed once again after he led for most of the first moto. In the end he ended up with a respectable podium overall position.

The Verdict
With as many kids riding fully custom 90 and 150cc quads these days, perhaps Kevin’s wish just might be around the corner. The 250 may be the perfect stepping stone for today’s youth ATVer. And from the looks of this SRF YFZ250, many of them might elect to not move up to a 450 at all. What’s more, this mighty little “youth” ATV just might be the perfect quad for many smaller adults as well. Theo sums it up, “I’m really happy with the way it turned out. We’re still in the testing stages right now, so there’s room for improvement for sure. Maybe with a newer engine we could get a little more torque and power, but all in all it’s a great little quad and I would love to see Yamaha make something like this.”

Who knows perhaps the word will travel fast, make its way into Japan and we’ll see a production Yamaha YFZ250 in the near future. Only time will tell.

Engine	Specs/Manufacturer
Piston	stock
Bore	stock, 77.0mm
Stroke	stock,53.6mm
CDI Box	stock250f
Clutch	stock250f
Exhaust	SRF modified stock headpipe with DR.D yfz tail ppipe
Cam	04 yz250f
Starter	SRF modifieed kick
Carb	keihin fcr-mx37
Horsepower	40 / stock
Top Speed	55mph
Bore & Stroke	77×53.6
Chassis	Specs/Manufacturer
Frame	SRF Modified Stock yfz
A-arms	SRF +2 long travel mx
Swingarm	SRF stock length
Steering Stem	Tag
Axle	Team
Front Shocks	Ohlins PRX
Rear Shock	Ohlins PRX
Dry Weight:	345
Controlls	Specs/Manufacturer
Pegs	IMS
Bars	Tag
Clutch lever	YFZ
Handguards	n/a
Grips	Tag
Throttle	YFZ Thumb
Tether Kill Switch	Pro Design
Shifter	YZ250f
Brake Pedal	YFZ stock
Steering Stabilizer	GPR
Other:	Specs/Manufacturer
Spindles	stock
Hubs	frnt: LSR, rear: Team
Gas tank	stock
Gearing	13, 40
Front Bumper	Tag
Rear Grab Bar	06 stock yfz
Nerf Bars	AC
Fuel	50/50 mix C12& 92 octane
Oil	Maxima
Chain	DID
Fenders	stock/ SRF modified
Brakes	Galfer
Rear Wheels	ITP T9 Baja
Front Wheels	ITP T9 beadlock
Rear Tires	ITP SX
Front Tires	ITP QuadCross

Tags:

Comments

comments