2010 Yamaha YZ450F Press Intro Videos

[RMZracer212]

I am going on 160 hrs on my RMZ 250 and have only done one valve adjustment. Now I have a customers CRF 250 with 55 hrs on it and I have already had to replace the intake valves, and re cut the seats. The valve it self went bad not the seats.

[cowboyona426]

Originally Posted by MotoMan

Oh and Chase, I am not nervous about valves at all...you ride these things long enough (four strokes) its just part of the game, thats all. And for what its worth I got 110 hours out of my first set of Honda valves.

Yes I'm aware that valves will wear out eventually. But, when the valves are made improperly they wear out faster than normal, which is the problem Honda has had in the past. I don't think it has a dang thing to do with the number of valves in the head.

[MotoMan]

Originally Posted by cowboyona426

Yes I'm aware that valves will wear out eventually. But, when the valves are made improperly they wear out faster than normal, which is the problem Honda has had in the past. I don't think it has a dang thing to do with the number of valves in the head.

As they say......time will tell!!

[cowboyona426]

Originally Posted by MotoMan

As they say......time will tell!!

For sure! I don't follow street bikes at all, but I know the R1 has been a 4 valve head for a few years now and I haven't heard of any issues with those. Hopefully it has the same durability/reliability of the older bikes.

[Woody_393]

The R1 does have Ti intakes (SS exhaust).

The WR250 still has 5 Ti valves -- the 2010 hasn't been released yet.

I really hope I'm wrong and Yamaha's are bullet proof as the other manufacturers are seemingly proving as well. I'm just not sure what Honda's deal is. It would seem that Honda pride stops them from making valves the correct way, i.e., the same way the other manufacturers are.

[cowboyona426]

The 2010 250F is a 5 valver, I highly doubt Yamaha will be doing anything major with the WR line this year but it is peculiar that they don't have the specs out yet...

[pjg351]

Originally Posted by Woody_393

The WR250 still has 5 Ti valves -- the 2010 hasn't been released yet

The new WR r 250 has 4 valves and FI and 30,000 k valve services, this will be the new engine for the 250 YZ ,WR f bikes in time, maybe next year. As far as Honda, our bike shop sponsor has a shed full of low hour valve job problems waiting to be fixed, pick a cc there all the same he reckons.

[Woody_393]

So the valves are Ti in the WR?

[pjg351]

Cycle news test: The YZ450F is like no other 450F we've ever ridden: It's ultra nimble, feels extremely light (even though it gained some weight over the '09 YZ), handles well and has tons of useable power - all of the things Yamaha said it would have.

And it turns like no other YZ450, too. It stays in the ruts and rarely stands up halfway through the turns. Steering is effortless and it goes where it's pointed, no questions asked.

[Aus_Rider_22]

Originally Posted by pjg351

The new WR r 250 has 4 valves and FI and 30,000 k valve services, this will be the new engine for the 250 YZ ,WR f bikes in time, maybe next year. As far as Honda, our bike shop sponsor has a shed full of low hour valve job problems waiting to be fixed, pick a cc there all the same he reckons.

Don't know where you are getting your info from Pete but I am 99% sure the 2010 WR250F will have 5 titanium valves.

IMO there is no way Yamaha would say 30k service limit for valves on a bike that bases it's engine on a high-revving MX machine.

I could be wrong, happens many times a day but I think the 4 valve setup isn't happening for Yamaha WRF's yet. Do you have a source?

[pjg351]

Originally Posted by Aus_Rider_22

Don't know where you are getting your info from Pete but I am 99% sure the 2010 WR250F will have 5 titanium valves.

IMO there is no way Yamaha would say 30k service limit for valves on a bike that bases it's engine on a high-revving MX machine.

I could be wrong, happens many times a day but I think the 4 valve setup isn't happening for Yamaha WRF's yet. Do you have a source?

Really, i did say maybe next year, This is the new engine that is out now and will in time be used in the other 250f race bikes, it's a natural progression from 5 to 4 valves just like the 450, and yes the 30,000 k valve service is what is currently used in the new WRr 250f, look it up!

Yamaha web site
Brand new liquid-cooled 4-valve engine with fuel injection. Adopting the same short stroke dimensions as the YZ250F and WR250F, the Supertrail engine features a compact combustion chamber and a 11.8:1 compression ratio that produces maximum power output at an astonishing 10,000rpm.
Large diameter titanium intake valves and high lift cams with excellent follow and lift characteristics allow high rpm levels. Downdraft-type straight air intake layout combined with fuel injection and pent roof combustion chamber result in a quick ignition flame spread. Which in turns means strong power and instant throttle response.
Fuel injection system also promotes excellent fuel economy and environmental friendliness. Sensors monitor crank, intake air pressure and throttle position and feed info to a super-compact ECU unit to calculate optimum fuel volume and injection timing.
Plated cylinder features a lightweight forged piston with a piston cooler. By eliminating materials with different heat-transmission rates from the liner, cooling efficiency is improved and oil consumption is also reduced.
Weight saving wet sump engine lubrication system has fewer auxiliary parts than dry sump. And the new engine’s three axis layout (the relative positions of the crank shaft, the main shaft and the drive shaft) further concentrates mass for improved handling.
Smooth operating clutch combines with a six speed gearbox to provide slick shifting and a gear for every occasion.
Supersport type large capacity ACM (Alternative Current Magnet) alternator is adopted to provide abundant and reliable electricity supply for lighting, spark and fuel injection system. Spark is further aided by direct ignition coil.
A three stage expansion chamber type muffler layout has been designed to bring the muffler closer to the machine’s centre of gravity for lighter handling. Air induction system and honeycomb type catalytic converter enhance environment-friendly performance. Exhaust gases are further filtered by a honeycomb type catalytic converter, which consists of a stainless steel tube coated with platinum and rhodium.
The first three section semi-double cradle frame ever on a Yamaha dual purpose model adopts technology from the proven aluminium frames on the YZ250F and WR250F. It consists of cast/forged aluminium main frame mated to a high tensile steel down tube and swingarm. The result is an outstanding blend of weight balance and strength/rigidity.
Plush upside down 46mm diameter fork with 270mm stroke provides excellent cushioning while the fork under-bracket is made of high-strength forged aluminium and the handlebar crown is cast aluminium for superior rigidity balance.
Slim steel fuel tank is shaped for excellent knee grip. Handlebar, seating and footrest locations create a comfortable riding position for road or dirt. Seat height is lower than WR/YZ at 895mm so a wider range of riders can feel at ease. But ground clearance remains a generous 300mm for serious off road performance.
Trick digital display LCD speedo has diagnostic function for fuel injection system as well as stopwatch and distance compensation tripmeter.



SPECIFICATIONS



ENGINE/IGNITION/TRANSMISSION
Type 250cc liquid-cooled DOHC 4-stroke;
Displacement - (cc) 250
Bore Stroke - (mm) 77.0 x 53.6
Compression 11.8:1
Fuel Management Fuel Injection
Ignition Direct ignition coil
Fueltank - (L) 7.5
Transmission Constant-mesh 6-speed;multiplate wet clutch
CHASSIS
Length - (mm) 2174
Width - (mm) 810
Height - (mm) 1229
Seat Height - (mm) 929
Wheelbase - (mm) 1419
Clearance - (mm) 300
Wet Weight 125kg with 7.5 litres of fuel
FRONT END
Suspension Front Inverted fork; fully adjustable, 270mm travel
Tyres Front 80/100-21
Brakes Front Hydraulic single-disc brake, 250mm
REAR END
Suspension Rear Single shock; fully adjustable, 270mm travel
Tyres Rear 120/80-18
Brakes Rear Hydraulic single-disc brake, 230mm

[Aus_Rider_22]

Originally Posted by pjg351

Really, i did say maybe next year, This is the new engine that is out now and will in time be used in the other 250f race bikes, it's a natural progression from 5 to 4 valves just like the 450, and yes the 30,000 k valve service is what is currently used in the new WRr 250f, look it up!

Yamaha web site
Brand new liquid-cooled 4-valve engine with fuel injection. Adopting the same short stroke dimensions as the YZ250F and WR250F, the Supertrail engine features a compact combustion chamber and a 11.8:1 compression ratio that produces maximum power output at an astonishing 10,000rpm.
Large diameter titanium intake valves and high lift cams with excellent follow and lift characteristics allow high rpm levels. Downdraft-type straight air intake layout combined with fuel injection and pent roof combustion chamber result in a quick ignition flame spread. Which in turns means strong power and instant throttle response.
Fuel injection system also promotes excellent fuel economy and environmental friendliness. Sensors monitor crank, intake air pressure and throttle position and feed info to a super-compact ECU unit to calculate optimum fuel volume and injection timing.
Plated cylinder features a lightweight forged piston with a piston cooler. By eliminating materials with different heat-transmission rates from the liner, cooling efficiency is improved and oil consumption is also reduced.
Weight saving wet sump engine lubrication system has fewer auxiliary parts than dry sump. And the new engine’s three axis layout (the relative positions of the crank shaft, the main shaft and the drive shaft) further concentrates mass for improved handling.
Smooth operating clutch combines with a six speed gearbox to provide slick shifting and a gear for every occasion.
Supersport type large capacity ACM (Alternative Current Magnet) alternator is adopted to provide abundant and reliable electricity supply for lighting, spark and fuel injection system. Spark is further aided by direct ignition coil.
A three stage expansion chamber type muffler layout has been designed to bring the muffler closer to the machine’s centre of gravity for lighter handling. Air induction system and honeycomb type catalytic converter enhance environment-friendly performance. Exhaust gases are further filtered by a honeycomb type catalytic converter, which consists of a stainless steel tube coated with platinum and rhodium.
The first three section semi-double cradle frame ever on a Yamaha dual purpose model adopts technology from the proven aluminium frames on the YZ250F and WR250F. It consists of cast/forged aluminium main frame mated to a high tensile steel down tube and swingarm. The result is an outstanding blend of weight balance and strength/rigidity.
Plush upside down 46mm diameter fork with 270mm stroke provides excellent cushioning while the fork under-bracket is made of high-strength forged aluminium and the handlebar crown is cast aluminium for superior rigidity balance.
Slim steel fuel tank is shaped for excellent knee grip. Handlebar, seating and footrest locations create a comfortable riding position for road or dirt. Seat height is lower than WR/YZ at 895mm so a wider range of riders can feel at ease. But ground clearance remains a generous 300mm for serious off road performance.
Trick digital display LCD speedo has diagnostic function for fuel injection system as well as stopwatch and distance compensation tripmeter.



SPECIFICATIONS



ENGINE/IGNITION/TRANSMISSION
Type 250cc liquid-cooled DOHC 4-stroke;
Displacement - (cc) 250
Bore Stroke - (mm) 77.0 x 53.6
Compression 11.8:1
Fuel Management Fuel Injection
Ignition Direct ignition coil
Fueltank - (L) 7.5
Transmission Constant-mesh 6-speed;multiplate wet clutch
CHASSIS
Length - (mm) 2174
Width - (mm) 810
Height - (mm) 1229
Seat Height - (mm) 929
Wheelbase - (mm) 1419
Clearance - (mm) 300
Wet Weight 125kg with 7.5 litres of fuel
FRONT END
Suspension Front Inverted fork; fully adjustable, 270mm travel
Tyres Front 80/100-21
Brakes Front Hydraulic single-disc brake, 250mm
REAR END
Suspension Rear Single shock; fully adjustable, 270mm travel
Tyres Rear 120/80-18
Brakes Rear Hydraulic single-disc brake, 230mm

Ahhh now I see where I lost you. I was thinking you were referring to the WR250F but you're talking about the WR250R. It's a "supertrail"/dual sport bike. By doing some reading I think it is supposed to fit in between a high-revving offroad bike, the WR250F, and the more road orientated air cooled TTR250.

Interesting to know since I didn't realise they produced such a bike.

I'd say the WR-R will be to Yamaha how the XR range was for the Hondas. A good solid reliable on/offroad bike. I'd bet it would have a bit more oomph than the XR250 though!

Just found a review the Courier Mail did on it. You're pretty spot with the service intervals. 1000ks, then 10,000ks then 40,000ks after that.

We're on the same page now.

[pjg351]

Originally Posted by Aus_Rider_22

Ahhh now I see where I lost you. I was thinking you were referring to the WR250F but you're talking about the WR250R. It's a "supertrail"/dual sport bike. By doing some reading I think it is supposed to fit in between a high-revving offroad bike, the WR250F, and the more road orientated air cooled TTR250.

Interesting to know since I didn't realise they produced such a bike.

I'd say the WR-R will be to Yamaha how the XR range was for the Hondas. A good solid reliable on/offroad bike. I'd bet it would have a bit more oomph than the XR250 though!

Just found a review the Courier Mail did on it. You're pretty spot with the service intervals. 1000ks, then 10,000ks then 40,000ks after that.

We're on the same page now.

Geoff, the word is this engine will become the standard 250f race version as well with obviously some more go go juice. The Wr r was the guinea pig for development of the 4 valves and the FI, it's a big success by all reports, another triumph for Yamaha.

[DRGSin393]

Originally Posted by pjg351

.... it's a big success by all reports, another triumph for Yamaha.

I bet that hurt to say didnt it Petey?

[Aus_Rider_22]

Originally Posted by DRGSin393

I bet that hurt to say didnt it Petey?

I bet it did!

But seriously if that's the bike the YZ250F's are following, I like. Didn't think I would see the day when I thought a Yamaha 4-valve MXer would be introduced after the "5 valve ti revolution".

Can't wait to buy a little dirt cycle in the next year or 2.

[cowboyona426]

New vid of numba 7 on the 2010 450F:

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