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getdrunk

YZ400/426 whats different bout them?

15 posts in this topic

how much hp does a piped 426 have?

how much hp does a piped 400 have?

is their much of a difference in the motors?

are the motor mounting locations the same?

can yz426 motor parts fit the yz400

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2000 wr400- 55hp @ 8000 rpm

2001 wr426- 58hp @ 9000 rpm; 36 ft.ibs @ 7000 rpm :thumbsup:

Different pipes will give you different performance. After changing your exhaust you will have to jet the carb to compliment the change in air flow.

I think the 400 and 426 have the same stroke but the 426 has the bore of a 450. So actually the 426 cylinder and piston will fit the 400. They also have big bore kits available.

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how much hp does a piped 426 have?

how much hp does a piped 400 have?

is their much of a difference in the motors?

are the motor mounting locations the same?

can yz426 motor parts fit the yz400

Engine locations are the same, same frame on both bikes!!

A lot of engine components are the same, it's easier to convert a 400 to 426..

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2000 wr400- 55hp @ 8000 rpm

2001 wr426- 58hp @ 9000 rpm; 36 ft.ibs @ 7000 rpm :thumbsup:

No offense but your about 10hp off. A new 2005 yz450 makes about 49hp

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No offense but your about 10hp off. A new 2005 yz450 makes about 49hp

What are you talking about kid, a 450?

The guy asked about a 400 and 426 so numskull was right.

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What are you talking about kid, a 450?

The guy asked about a 400 and 426 so numskull was right.

Well I don't really know how much a 400 or 426 makes so I was comparing it with facts that I did know to show that he wasn't very close. There's no way A 400 is making 55hp especially a wr.

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hot start on the 400 is remote....426 is intergrated on the carb... do google image search and go 4rm there

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What are you talking about kid, a 450?

The guy asked about a 400 and 426 so numskull was right.

have to agree with "kid" ..

theres no way a 426 makes 58 hp ...

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They are not the same frames.

There really is nothing beyond the gas tank that is the same on the 2 bikes. Every year the 400 and 426 had some serious updates.

If you want all the details, go to your yamaha dealer and get the technical seminar update books from 99-02. They will list ALL the details of the new models.

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Heres some links to the source of the HP ratings.

2000 wr400

2001 wr426

I have no idea where they got those specs, but I'm assuming thats what Yamaha claimed, and thats probably the hp rating at the crank.

after free mods for the wr's rear wheel hp is somewhere around 43 and 45 respectively, bringing them very close to the performance of the yz's.

I think its safe to assume that theres probally about a 2 hp difference between 26cc's :thumbsup:

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well what was all the changes dun to the motors over the years?

also im talking about the YF motors not the WR even though their isnt to much difference in the motors

im going to be buying a motor for my quad and was thinking of getting a yz400 motor instead of the 426 because i can get them for like $400 cheeper than the yz426 motors.

The motor i might buy comes with carb////electronics/// 450 auto decompression cam in it.

i think its a 99 motor. any problums with that year?

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from everything that I've read the 400 is one of the most reliable motors out there. I have a 98 yz400 and it would rip my arms off if I'd let it :thumbsup:

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