426 power "hit" vs. late model 450 hit?

[SCORPiON5150]

I ride an 01 YZ426F and love the way it makes it's power - what most people complain about. I love the abrupt 2-stroke-like on/off power delivery that yamaha worked so hard to smooth out over the years. My friends' CRFs and the only yami 450 I have ridden (05) feel like an XR250 in comparison to my 426, as far as delivery goes. Any way to make say an 06-08 450 run with the aggressive, arm ripping power of my 426? Anyone know what they changed over time to smooth out the power delivery? I assume it's mostly ignition mapping and carb setup. I wanna stay true to blue as far as my thumpers go but this has been holding me back for 4 years now from replacing the 426!

[felix4x4]

The smothed out power is what makes the new 450's so tractable. They dont just snap into the power so you can roll on earlier in turns and keep traction in the loose stuff. They still rev fairly quick. I still like the way a 2 stroke comes into the powerband, but the thumpers make it so much easier on you when it comes to putting down the power.

[grayracer513]

A great deal has been made of the "softening of the power curve", and people mistake it to mean the power was reduced. If you want all the power that your 426 has, and in fact about 3-4 more, all you have to do is pin it. The difference is that the bike no longer explodes to life as soon as the throttle is touched, and the throttle is as much like a rheostat on an electric motor as anything I can remember riding.

Until you've ridden one, don't sell it short. A good '06 is absolutely stronger than any stock 426, just like it is.

[KAS]

All I remember from the old 426's was a lotta noise and no go.

New 450's run off and hide from them.

[The Italian Stallion]

I had an 01 426 and I liked it alot. If the bike was 30lbs lighter I would still have it. In comparison to my 06 YZ450 I would say that the 426 had more grunt off the bottom even more grunt than current hondas. The 06450 however rips from mid to top compared to the 426 and has way less engine brake. The 06 is easier to ride fast because it is lighter and has better suspension.But IMO the 426 turned way better. I wish they kept the same geometry

[SCORPiON5150]

The smothed out power is what makes the new 450's so tractable. They dont just snap into the power so you can roll on earlier in turns and keep traction in the loose stuff.

A great deal has been made of the "softening of the power curve", and people mistake it to mean the power was reduced. If you want all the power that your 426 has, and in fact about 3-4 more, all you have to do is pin it.

I know the 450s make more power, and I know it is much more useable power, and more tractable than the 426 ever thought of being. I am not at all trying to say the 450 is a slouch.

What I should have mentioned in my previous post is that out of my 5 dirt bikes, the 426 is the only thumper. The rest of my bikes are ALL big bore 2 stroke. 2000 and 91 CR500s, a YZ490, and a husky 500CR. I ride primarily nasty tight northern california single track on these montrous 2 stroke beasts, often using every measurable unit of power and throttle response.

Needless to say, once you become accustomed to that kind of power and the way these bikes put it to the ground, along with training your right hand to not get you killed, it is very hard to turn back. In comparison even my 426 makes it's power like a toat goat so even that has been a compromise in my riding style. It's still my favorite bike out there, but only because of the aggressive power delivery that is at least remotely comparable to the big 2 strokers I have been riding for years.

I have been ready to replace it with a 450 for several years now, but just know I cannot live with the power delivery, especially hopping off a 66HP CR500 that will throw you off the back if your right hand gets sloppy.

This all being said, anyone have any ideas on how to acheive my goal of making a newer bike respond like my 426 does? 2 ideas that come to mind for me are to try a modified throttle tube, or to heavily work the engine on a 450 (bore, stroke, porting, exhaust, zip-ty carb mod, and every other power mod imagineable) in an effort to make the bike have so much "unusable" power that it responds very aggressively. My personal thoughts are that modding the engine still won't achieve my goals, but the throttle tube may make a huge difference.

Thoughts, anyone?

[c-man]

I just got rid of my 01' 426 and traded up for a new 06' last April. I loved the 426 so much, and was apprehensive about letting it go (as I was when I sold my 99' 400F to go to the 426). I wanted the 06' as I knew they had more muscle than the 07', and I recently rode an 08' and I am sure they are just as fast and have as much or more HP's than the 06', but they just don't have the hard pulling fun factor of the 06'. As far as the 06' vs. my cherry 01', the 06' has more muscle everywhere.....it just feels a little less like a traditional thumper and a little more like a flickable 2-stroke. I have never been happier with a bike than the 06'. I also like the big pull feel as I ride trail and hare scramble, and let me tell you, the 06' will not let you down. I am 6', 205#, 31 y/o and have been riding for 28 years, and this is the best bike I have ever owned!!

C

[grayracer513]

(I) just know I cannot live with the power delivery, especially hopping off a 66HP CR500 ...

Thoughts, anyone?

That would be like this one, right? I'm intimately familiar with them, as with all kinds of big 4-stroke singles. On pavement it's one thing. The bike below posted 70 hp on a dyno with the PC pipe on it, and then started throwing chunks of rubber around the room. However, there is no place in the dirt my my '06 YZ450's aren't actually faster (dunes with a paddle might well be the exception), and the thumpers are actually somewhat lighter.

But, you can re-work the engines, and quick turn throttles are out there.

[SCORPiON5150]

That would be like this one, right? I'm intimately familiar with them, as with all kinds of big 4-stroke singles. On pavement it's one thing. The bike below posted 70 hp on a dyno with the PC pipe on it, and then started throwing chunks of rubber around the room. However, there is no place in the dirt my my '06 YZ450's aren't actually faster (dunes with a paddle might well be the exception), and the thumpers are actually somewhat lighter.

But, you can re-work the engines, and quick turn throttles are out there.

Yeah, something like that one! Pretty sweet looking too I might add. I've seen some revelation about the 06 450s being a little snappier than the 07 as well. Are they gradually making the 450s more and more user friendly or what's the deal there? Is an 07 or 08 vs. an 06 just like the delivery changes between 426 to 450?

[grayracer513]

The '06 has more low end grunt than an '07, which has more top end. The '08, once you put an aftermarket exhaust on it, has more of both than either of them.

[917 rider]

The '06 has more low end grunt than an '07, which has more top end. The '08, once you put an aftermarket exhaust on it, has more of both than either of them.

+1:thumbsup:

[917 rider]

heres a link to that throttle tube http://www.atvprice.com/shopping/g2/g2_ergo.htm go down the page a little they have what you want:thumbsup:

[SCORPiON5150]

heres a link to that throttle tube http://www.atvprice.com/shopping/g2/g2_ergo.htm go down the page a little they have what you want:thumbsup:

That looks like just the ticket as far as a tube goes, except 1 thing. They only list up to 06 for the YZs. While the 06 may be light years ahead of the 426 in technology, I would be shooting for an 07-08 model, likely the 08 from what you guys are saying about the power differences. Perhaps I will put one on my friends CRF450X and see how it rides then. I have the same power delivery woes as the YZ450F on it. Hell, maybe I'll just put one on my 426 and it will be the best 4 stroke for my style?? I would imagine it to be more uncontrolable than any 450 with that throttle!

[grayracer513]

'08 throttle tubes are the same part number.

[917 rider]

That looks like just the ticket as far as a tube goes, except 1 thing. They only list up to 06 for the YZs. While the 06 may be light years ahead of the 426 in technology, I would be shooting for an 07-08 model, likely the 08 from what you guys are saying about the power differences. Perhaps I will put one on my friends CRF450X and see how it rides then. I have the same power delivery woes as the YZ450F on it. Hell, maybe I'll just put one on my 426 and it will be the best 4 stroke for my style?? I would imagine it to be more uncontrolable than any 450 with that throttle!

you know i too was once like you,power hungry,i had a crf 450 and put a rpms 500 ice cube kit in it and every thing else you can think of.i have a 06 suzuki rm 250 two stroke with a 300 kit and just sold my 07 kx 450 then something funny happened i bought a 08 yz 450,with smooth power and rode at the same tracks hmmmmmmmmmmmm whats this i can ride longer,turn the power on faster in the turns,lower my lap times and become a better rider.times change let go ,theres light at the end of the tunnel ,ive found to much is a bad thing,but the right amount is sweeeeeeeeeeeeeeeeet,

[oldnbold]

I may be talking out of school here, but wasn't the 03 yzf450 the king of snappy HP? Didn't the ignition mapping and the camshaft's profile make it a real bitch to hang onto?

I had a '00 426 and loved it......test rode a new '03 in '03 and decided it was way too much motor for my taste.

Maybe a mating of the '03 CDI to an "06 or "07 would be the ticket.

[SCORPiON5150]

I may be talking out of school here, but wasn't the 03 yzf450 the king of snappy HP? Didn't the ignition mapping and the camshaft's profile make it a real bitch to hang onto?

Can anyone give any more insight on this?

Maybe a mating of the '03 CDI to an "06 or "07 would be the ticket.

Or this?

[grayracer513]

The '03 was roundly criticized for its explosive low/mid power delivery, yes. And nearly all of it was due to ignition mapping. I do not believe the '03 CDI will work with the later harnesses, but you can buy a Vortex or Power Commander and tweak it.