whats all the talk about yz426 motors breaking?

what all goes wrong on the motors? i been hereing alot of talk that the yz426 has alot of motor problums. i need to know if its that much trouble having one. need to no if i should put that motor n my 400ex or just get a yfz450.

bottom line??? The 426 debuted in the fall of 1999....these bikes are getting old and most people (unfortunately) don't stay up with the maintenance.

The 426 is as bullet proof as any mx bike (especially thumper) ever made. But they too wear out.

well i have a 400ex. their called bullet proofe to and it cazed me nothin but trouble. so i dont want a nuther bad motor

the 01-02 426 is as trouble free as any mechanical device you will find.

These things are breaking? Could've fooled me. I checked my valves a few weeks ago and they are spot on straight out of the factory. Just get a newer one with a good maintenance record and you should be fine.

With 12000+ miles on my WR426, about 1000 of them on the MX track, I keep waiting for something to break but I swear the damn thing runs better and faster than the day I bought it 4 years ago. I'm about to pick up a new 2006 YZ 450 and if it's half as good as my 426 I'll be happy.

They are tough, period!

Not 1 prob. here :thumbsup:

The 426 has a rep for being an extremely reliable MX bike. Definitely one of the best MX bikes in terms of reliability. Of course you're talking about putting the motor into a quad frame, and I have no idea what happens to the motor when it's put into a quad.

The 426 has a rep for being an extremely reliable MX bike. Definitely one of the best MX bikes in terms of reliability. Of course you're talking about putting the motor into a quad frame, and I have no idea what happens to the motor when it's put into a quad.

thats what i want to no is if it will last in my quad. i no their will b more stress on the motor sinse theirs more weight n wheels to turn.

I'm sure the YFZ motor would be better as it's got quad-specific features, but you might want to post in some quad boards to see how the 426 has held up for others in the quad application.

The motor was designed for a bike not a couch. Who knows how long it will last, I would say the trans will give up first.

Or you could just ride the bike and save yourself alot of time and energy.

putting a bike engine in a quad is not a very good idea because i wanted to put a kx500 engine into my tecate 4 so i asked people on an atv forum and everyone said that a bike in a atv engine means alot of vibrations because of alot of diff reasons and itll put more stress on the tranny than it can handle but if you really want to do it and dont care about vibration than get a steering stem with a a plastic that cuts down vibrations and use alot of loc-tite

how about the yfz450 quad?

is'nt that the same engine as the yz450f?

how about the yfz450 quad?

is'nt that the same engine as the yz450f?

The engines are similar but not identical. I don't know 100% for sure, but I suspect some of the internals are a bit more beefy (such as tranny gears) and it's likely tuned a bit differently (cams and carburetion).

No problems with my 2002 426 - everything to spec and still running strong

My 2000 runs like a top.

The engines are similar but not identical. I don't know 100% for sure, but I suspect some of the internals are a bit more beefy (such as tranny gears) and it's likely tuned a bit differently (cams and carburetion).

saw you wrote that a little higher up in the thread :thumbsup:

but couldnt the extra stress on the tranny be lowered by using higher gearing (+ the smaller wheels on the quad)?

but who want´s a slow quad anyway ... :thumbsup:

saw you wrote that a little higher up in the thread :thumbsup:

but couldnt the extra stress on the tranny be lowered by using higher gearing (+ the smaller wheels on the quad)?

but who want´s a slow quad anyway ... :bonk:

I'm with you Fizz, who would want to butcher a perfectly good 426 and use its parts for a quad? Quads = :thumbsup:

I'm with you Fizz, who would want to butcher a perfectly good 426 and use its parts for a quad? Quads = :bonk:

yeah .. there are much nicer engines for the heavy quads .. like the ones talked about in the thread "426 MX-bike vs. 600cc road bike" .... :thumbsup:

i want a quad with a 900-1000cc engine .... :thumbsup:

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now