440ex vs yfz

[nhyfzrider]

300 yard drags, piped and jetted, anybody seen this happen?(no cam mod for yfz)

[jeepeater347]

Ya This weekend I seen a very good running 440ex beat 3 different piped and cam modded YFZ's in a 300 ft dirt drag the 440 won by about 2 lenghts

[Freestylemxr]

Wow I was wondering that myself too, if only there was a 450 kit for the ex...

[K_Fulk]

Originally posted by Freestylemxr
Wow I was wondering that myself too, if only there was a 450 kit for the ex...

All you have to do is stroke it 4mm and put a 88 mm piston in one. :cool:

[TC426EX]

Originally posted by K_Fulk
All you have to do is stroke it 4mm and put a 88 mm piston in one. :cool:

Exactly...

a 426 with a 4mm stroker crank has 450cc displacement...

[One_Bad_400]

i have a 416 in my ex and my friend has a yfz with the baffle out, lid out, and cam mod and i still beat him

[montyjcm]

Nice, by how much?

[Freestylemxr]

Originally posted by K_Fulk
All you have to do is stroke it 4mm and put a 88 mm piston in one. :cool:

Will that keep up with a yfz?

[250ex_guts]

my friend has a 416ex and he smokes yfz'z and 450r's he beats them both by about 1 length but then again he got the holeshot his first time racing stock to a 250r and pros so i dunno if it is him or the quad

[K_Fulk]

It should be ahead of it.

[sparky450AR]

Here are some vids of well built 440ex's against piped YFZ450's.

The username is mv@insightbb.com , password is cannon .


http://www.eengoedidee.nl/videoz/mx/cimg1067.avi

http://www.eengoedidee.nl/videoz/mx/cimg1069.avi


This class came down to two highly modded, 440ex's. There were stock 450r's, YFZ's, and even a 300ex running on meth.

http://www.eengoedidee.nl/videoz/mx/cimg1070.avi




If you guys want even more videos, I have them! By the way, this is a 300 foot, groomed dragstrip with a tree. Everything was fair both races. I also have vids of them beating 450R's.

[sparky450AR]

Originally posted by sparky450AR
Here are some vids of well built 440ex's against piped YFZ450's.

The username is mv@insightbb.com , password is cannon .


http://www.eengoedidee.nl/videoz/mx/cimg1067.avi

http://www.eengoedidee.nl/videoz/mx/cimg1069.avi


This class came down to two highly modded, 440ex's. There were stock 450r's, YFZ's, and even a 300ex running on meth.

http://www.eengoedidee.nl/videoz/mx/cimg1070.avi




If you guys want even more videos, I have them! By the way, this is a 300 foot, groomed dragstrip with a tree. Everything was fair both races. I also have vids of them beating 450R's.


what do yall think of that?:)

[danyeo]

Originally posted by sparky450AR
what do yall think of that?:)

If you guys think your 440's and 416's are faster than the yfz's it's the rider factor and also how big the wallet is and not the type of quad. Any type of quad can win in a 300 foot drag, it's a lot of rider ability. When it's a long drag or a sand hill drag the YFZ absolutely destroy's 416's and 440ex's. A 400ex stock weighs 375 lbs and has maybe 27hp when a YFZ is 350lbs and has 39-40 hp stock. A good 440ex should have around 34-38 hp and it's still behind in power to a stock YFZ. Those 440's in the videos look pretty fast though and i also wonder how much money they have invested in them.

[sparky450AR]

Originally posted by danyeo
If you guys think your 440's and 416's are faster than the yfz's it's the rider factor and not the quad. Any type of quad can win in a 300 foot drag, it's all rider ability. When it's a long drag or a sand hill drag the YFZ absolutely destroy's 416's and 440ex's. A 400ex stock weighs 375 lbs and has maybe 27hp when a YFZ is 350lbs and has 39-40 hp stock. A good 440ex should have around 34-38 hp and it's still behind in power to a stock YFZ.

I own a 450R, why would I try to put them down? Trust me, these 440's were faster than any yfz or 450R there. They were obviously VERY well built 440's. Your kidding yourself if you dont think a 400cc motor can be built to stomp any stock 450.

[danyeo]

Originally posted by sparky450AR
I own a 450R, why would I try to put them down? Trust me, these 440's were faster than any yfz or 450R there. They were obviously VERY well built 440's. Your kidding yourself if you dont think a 400cc motor can be built to stomp any stock 450.

Yeah but for the amount of money i wouldn't bother.

[sparky450AR]

Originally posted by danyeo
Yeah but for the amount of money i wouldn't bother.

Ill have to agree with you there, unless you were in my dads posistion. Hes pissed off because his son is beating him:D , weve always talked trash. He's already got tons of money sunk into axis suspension, clutch, pipes, handlebars, wheels, look at the signature. He has so much money sunk into his bike that it would be dumb to sell it. Especcially if he can make it as fast as mine. This is the posistion a lot of other people are in.

[Chef]

Originally posted by danyeo
If you guys think your 440's and 416's are faster than the yfz's it's the rider factor and also how big the wallet is and not the type of quad. Any type of quad can win in a 300 foot drag, it's a lot of rider ability. When it's a long drag or a sand hill drag the YFZ absolutely destroy's 416's and 440ex's. A 400ex stock weighs 375 lbs and has maybe 27hp when a YFZ is 350lbs and has 39-40 hp stock. A good 440ex should have around 34-38 hp and it's still behind in power to a stock YFZ. Those 440's in the videos look pretty fast though and i also wonder how much money they have invested in them.

Ok, to start, you are right that the rider factor is most of it. But you are wrong that a YFZ is 350 lbs. Go buy some scales and throw a stock YFZ on em. I did, and sitting on the showroom floor at the dealer unserviced it weighed well over 390 lbs. My friends YFZ weighs over 400 ready to run. I'm not gonna say that the EX is any lighter, because its over 400 too when its full of fluids. My EX with an all aluminum rear end and HiPers was 358 wet. Even without the HiPers and aluminum axle, coming in at 398 ready to go, ate the built YFZ's for lunch. A GOOD 440EX should be mid 40's, not mid 30's. Mid 30's is like just throwing in a medium-high comp 440 piston with no cam or port work. Yea, it takes money, but it IS possible.

[danyeo]

And here is what a well built 450 can do, this is a CRF though before the 450r came out. I feel sorry for the YFZ in that race.

http://www.ljsoftware.com/Videos/Pismo.htm

Scroll down and look at the 400ex frame with the CRF on alky video.

[sparky450AR]

Originally posted by Chef
Ok, to start, you are right that the rider factor is most of it. But you are wrong that a YFZ is 350 lbs. Go buy some scales and throw a stock YFZ on em. I did, and sitting on the showroom floor at the dealer unserviced it weighed well over 390 lbs. My friends YFZ weighs over 400 ready to run. I'm not gonna say that the EX is any lighter, because its over 400 too when its full of fluids. My EX with an all aluminum rear end and HiPers was 358 wet. Even without the HiPers and aluminum axle, coming in at 398 ready to go, ate the built YFZ's for lunch. A GOOD 440EX should be mid 40's, not mid 30's. Mid 30's is like just throwing in a medium-high comp 440 piston with no cam or port work. Yea, it takes money, but it IS possible.

Did you by chance weigh the 450R? I have a feeling it weighs quite a bit less than the YFZ.


The thing about building a 400ex to compete with 450's is by the time you get it to that point you are to its full potential, unless you start getting into the HUGE bucks. But the 450's will still have tons of potential, because they will be stock.

[Fender Bender]

I rode Donnies EX the whole time I was up at his house...and I wouldn't put my money on a yfz.

[sparky450AR]

Originally posted by danyeo
And here is what a well built 450 can do, this is a CRF though before the 450r came out. I feel sorry for the YFZ in that race.

http://www.ljsoftware.com/Videos/Pismo.htm

Scroll down and look at the 400ex frame with the CRF on alky video.


wow, lol.....thats what im saying.....the 440 will be to its full potential while the 450 will still have tons of potential left.

[danyeo]

Originally posted by Chef
Ok, to start, you are right that the rider factor is most of it. But you are wrong that a YFZ is 350 lbs. Go buy some scales and throw a stock YFZ on em. I did, and sitting on the showroom floor at the dealer unserviced it weighed well over 390 lbs. My friends YFZ weighs over 400 ready to run. I'm not gonna say that the EX is any lighter, because its over 400 too when its full of fluids. My EX with an all aluminum rear end and HiPers was 358 wet. Even without the HiPers and aluminum axle, coming in at 398 ready to go, ate the built YFZ's for lunch. A GOOD 440EX should be mid 40's, not mid 30's. Mid 30's is like just throwing in a medium-high comp 440 piston with no cam or port work. Yea, it takes money, but it IS possible.

I was using dry weight, too many variables when you start adding fluid. the YFZ is 350lbs dry and a stock 400ex is around 375.

[Chef]

Originally posted by sparky450AR
wow, lol.....thats what im saying.....the 440 will be to its full potential while the 450 will still have tons of potential left.

True, but the YFZ's really dont have that much left in em. Sure, you can get some good HP out of em, but they are really peaky and dont last long...The CRF motors are alot better for this if you can find the parts. Our 500 friggin rails, but if it blows up we're done because the parts do not exist.

[RIDER11X]

Originally posted by Freestylemxr
Wow I was wondering that myself too, if only there was a 450 kit for the ex...

Contrary to popular belief, displacement is not always the key to speed.......Well built 416's, and 426's are often faster than a 440 bore kit, unless it is achieved with stroke also. Less piston weight = faster revving motors. Also MOST not all, 440's aren't so reliable either.

[sparky450AR]

Originally posted by danyeo
I was using dry weight, too many variables when you start adding fluid. the YFZ is 350lbs dry and a stock 400ex is around 375.

Thats what the manufacturers claim. Do you think both the 450R and the YFZ weigh exactly 350lbs dry? If you want to know the real weights, you gotta do what chef did, weigh them yourself.

[danyeo]

Originally posted by sparky450AR
wow, lol.....thats what im saying.....the 440 will be to its full potential while the 450 will still have tons of potential left.

I know, that quad is SICK. I have not seen a video of a faster 4 stroke yet. How many 4 strokes do you ever see beating Banshee's in the sand like that? And i doubt those Banshee's were stock.

[sparky450AR]

Originally posted by danyeo
I know, that quad is SICK. I have not seen a video of a faster 4 stroke yet. How many 4 strokes do you ever see beating Banshee's in the sand like that? And i doubt those Banshee's were stock.

I dont think i've ever seen a stock banshee, unless it was on the showroom floor. haha. On my first riding trip with my R I draged a banshee that had two in one carbs, holshots, and a cool head, and beat him by about a quad length in a 150 foot. I had a big smile on my face, and the group he was riding with was very impressed. This was back when only a small handfull of people had 450R's.

[Chef]

150 feet really isnt far enough for a Banshee....but good job dude. :cool:

[danyeo]

Originally posted by sparky450AR
Thats what the manufacturers claim. Do you think both the 450R and the YFZ weigh exactly 350lbs dry? If you want to know the real weights, you gotta do what chef did, weigh them yourself.

They are very close in weight. I had a YFZ and 450r and my C-Dale all together one day and i know it's not a way to judge a quads weight but by picking up each quad from the rear grab bar the YFZ and 450r "felt" the same weight and my Dale was noticably a little heavier. The YFZ had a rejet, no lid, cam mod, and stock pipe with the pea shooter out and it was very fast, i didn't get to race him because my F$%^ng Dale decided to blow up for the second time in the same year. Good ole American engineering! LOL

[sparky450AR]

Originally posted by Chef
150 feet really isnt far enough for a Banshee....but good job dude. :cool:

My R was just getting started too.:D

[sparky450AR]

Originally posted by RIDER11X
Contrary to popular belief, displacement is not always the key to speed.......Well built 416's, and 426's are often faster than a 440 bore kit, unless it is achieved with stroke also. Less piston weight = faster revving motors. Also MOST not all, 440's aren't so reliable either.

Your right, scott at profab atv told me he could never build a 440 as fast as he could build a 426. So thats what my dad is getting done next. Scott said that the 440's were mostly "hype".

[danyeo]

Originally posted by Chef
150 feet really isnt far enough for a Banshee....but good job dude. :cool:

YEah. My freind had a 370 Banshee and i raced him on my 400ex and i just had a pipe, it was sand and i had a lead into 4th gear, once his turf tamers decided to stop spinning he passed me like i was standind still, i was laughing my arse off. I hate they way the Banshee power comes on though. Twist the throttle and nothing happens then all of a sudden the power kicks in your arms are about to get ripped off and it sounds like an evil horde of killer bees, and i think they handle like poo!

[Chef]

Thats when you lighten the pistons-the piston in my 465 weighs less than the one in my friends 416. :cool:

[sparky450AR]

Originally posted by Chef
Thats when you lighten the pistons-the piston in my 465 weighs less than the one in my friends 416. :cool:

Did you "golf ball" the piston?

[Chef]

Originally posted by sparky450AR
Did you "golf ball" the piston?

What the heck is "golf ball" the piston? We lightened the skirt, and the fly cut for the valves takes a bit off. I personally havent seen the piston in this motor, and he didnt go into alot of detail as to how he lightens them, but he told me that it is a couple grams less than a standard JE 10.8 416 piston. The 500 piston in my CRF is only a couple grams heavier than the stock CRF piston.

[sparky450AR]

Originally posted by Chef
What the heck is "golf ball" the piston? We lightened the skirt, and the fly cut for the valves takes a bit off. I personally havent seen the piston in this motor, and he didnt go into alot of detail as to how he lightens them, but he told me that it is a couple grams less than a standard JE 10.8 416 piston. The 500 piston in my CRF is only a couple grams heavier than the stock CRF piston.

My cousin drag races every weekend in connersville indiana, hes got the best motor builder around. Golf balling the pistion is cutting out notches where the surface of the piston looks like a golf ball. I can get pics if you want them. It is supposed to lighten the piston A LOT, flow more oil through the cylinders, and add up to 2,000 extra RPM.(this is a banshee)

[Chef]

Oh, that makes sense. It turns good RPM right now...can easily go to 11k on stainless valves. The CRF goes to 14k with Ti valves and a custom built cam. Theres another 2k in the EX with going to the Ti valves...When I re-do the top end on the EX this season with a piston and rings and valve seals etc, I am going to up the compression some more, if I can, its already above 13.5, and go to alcohol....I really love the way it smells and the HP is just a plus.

[sparky450AR]

Originally posted by Chef
Oh, that makes sense. It turns good RPM right now...can easily go to 11k on stainless valves. The CRF goes to 14k with Ti valves and a custom built cam. Theres another 2k in the EX with going to the Ti valves...When I re-do the top end on the EX this season with a piston and rings and valve seals etc, I am going to up the compression some more, if I can, its already above 13.5, and go to alcohol....I really love the way it smells and the HP is just a plus.

Dam chef, youve got some toys! Alcohol is said to be as much as a difference as a blaster compared to a banshee. About a 30% power gain on a 2-smoke. Im gonna hit the sack....ill talk to you later.