YZ426 power
#22
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I think actually all those quad frames produce lots of power,but if you stuff the 426F motor in the Coleman Cooler on wheels it will fly like a **** and give you cool refreshments at the same time. Al you have to do is get a welder and weld a engine cradle to it and put a Bobcat 50 axle on it,but keep the plastic tires,they HOOK UP LIKE paddle tires! Add a set of Squishy Blend Gold Brew shocks and carbon fiber clarinet reeds and it will fly. For a pipe all you got to do is take you chrome shower head pipe out cut it to about 1 1/2 inches long and it will sound like a indy car,but have the chrome of a harley. Also make sure to stuff the carb with plastic bubble rap to add Mo POWER! The Coleman Cooler on wheels will go from cooler to BAD BI*CH. It will smoke any thing it looks at plus it rides in style with its light weight plastic frame and deep cooler. Now to keep the motor cool just fill the cooler up with ice before each ride and run a garden hose from the cooler to the 426 motr and wala instant coolness. Thats the best frame and motor combo. The COLEMAN COOLER produces 6000 cold RWHP and the motor with the mods done to it makes 4000 rwhp. Thats my input for the best thing ever! Thanks,Joe
#24
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Okay, guys, the actual horsepower of an engine doesn't decrease or increase dependant on the weight it has to drag around. The horsepower (as tested on a dyno) stays the same.
The weight does affect how the torque and horsepower respond in the real world though.
The rule of thumb is - you lose 1 hp for every 7 lbs of added weight. This is at peak, so it's not as dramatic in a drag race as it is in a tapped out, down the road, speed run.
The 426 engine is effective in a quad chassis. The internal gearing is it's main drawback, because of the smaller OD of the ATV wheels compared to the motorcycle. You're shifting that thing more often than a Banshee!
Cory Ellis is also running the Laeger chassied YZF this year, but he has it built to a 440 with a Powroll stroker, and likes it much better becuase he can gear it up and doesn't have to shift as often.
The weight does affect how the torque and horsepower respond in the real world though.
The rule of thumb is - you lose 1 hp for every 7 lbs of added weight. This is at peak, so it's not as dramatic in a drag race as it is in a tapped out, down the road, speed run.
The 426 engine is effective in a quad chassis. The internal gearing is it's main drawback, because of the smaller OD of the ATV wheels compared to the motorcycle. You're shifting that thing more often than a Banshee!
Cory Ellis is also running the Laeger chassied YZF this year, but he has it built to a 440 with a Powroll stroker, and likes it much better becuase he can gear it up and doesn't have to shift as often.
#26
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A 400 ex engine doesn't have pistons, rods, cams etc. Honda went all out with their "Obsolete Technology is High Technology, if you package it correctly. ( ie: Pushrod engines in a "High Performance" quad )
We all know that Honda puts a hampster on a treadmill inside those engine cases. Why didn't Honda liquid cool the engine ??? The Hampster would DROWN !!!! Then they would have the DAMNED PETA nutcases breathing down their necks.
We all know that Honda puts a hampster on a treadmill inside those engine cases. Why didn't Honda liquid cool the engine ??? The Hampster would DROWN !!!! Then they would have the DAMNED PETA nutcases breathing down their necks.
#27
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When it comes to sport quads, Honda has always taken the safe and easy route, compared to the other manufactures. The Honda 250r was by far the slowest in drag races, because it didn't utilize the power valve like the LT 250r and the tecate 4 did, but it did have a superior chassis that out performed the others. When Yamaha and Suzuki came out with the banshee and LT 500, Honda was to chicken to come out with a big bore machine.
Then when Honda came out with the XR 400 based 400EX in 1999, they put a milder cam than its dirt bike counter part, which then only produced a measly sowing machine like power of 27hp. And it still wasn't even in the same league as the the very first 250R that came out in 86. It would handle slightly better than the 250R, but the motor in the EX is its major weakness when it come to power.
Hopefully Honda will wake up and produce some cutting edge, high horse powered quads in the future.
Then when Honda came out with the XR 400 based 400EX in 1999, they put a milder cam than its dirt bike counter part, which then only produced a measly sowing machine like power of 27hp. And it still wasn't even in the same league as the the very first 250R that came out in 86. It would handle slightly better than the 250R, but the motor in the EX is its major weakness when it come to power.
Hopefully Honda will wake up and produce some cutting edge, high horse powered quads in the future.
#28
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<< Why didn't Honda liquid cool the engine ??? >>
Actually, the Honda 400EX engine is very efficient. It is liquid cooled. The liquid just happens to be oil. The only area not cooled by the current design that would be cooled by a water-cooled design is the cylinder.
Four strokes don't generate the cylinder temps that two strokes do. The head is where the heat is on a four stroke (that's where the exhaust goes).
Although Yamaha has proved a water-cooled four stroke will out-perform an oil cooled one, it is not because of the water cooling, but the water cooling allows them to run ligher parts with tigher clearances. You could build an oil-cooled four stroke to run as well as the YZF, it just wouldn't last as long.
<< Loss of 1 HP for every 7 lbs?? Does that mean a 200lb person on a 400EX brings it to 0 HP?? >>
It's a physics question. The answer can never be "zero" of course. Anyway, you're not taking torque into account either. Torque is not as affected by weight as horsepower. That's why a diesel truck can tow more weight than a gas powered vehicle (per cc).
A good way to look at it would be this:
A 250lb guy, a hill and two bikes. One is an XR250, with approximately 20 hp. The other, a CR 80, with the same hp (much less torque!).
Put the guy on the CR80, and point it at the hill. Will he make it up? Will he blow the engine trying?
Now put him on the XR250. He'll make it up the hill, and the engine will survive...But it won't be as fun to watch!
#29
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<< The Honda 250r was by far the slowest in drag races, because it didn't utilize the power valve like the LT 250r and the tecate 4 did, but it did have a superior chassis that out performed the others. >>
hahahahaha!!!! hohohohoh!!! ah.....(wiping tears from my eyes)....sigh.
Sorry about that! The LT250R was never as fast as the Honda, in fact, the last year they came out ('92 or whatever), the magazines said "Suzuki has finally made a quad that is comperable to the 1989 Honda 250R".
The Tecate 4 was a big disappointment. The 3 wheeler tecate was an awesome machine, and definitely faster than a TRX 250R. Everyone was disappointed in the Tecate 4, it was a slug.
Power valve technology allows a two stroke to generate better low end power by changing the size and height of the exhaust port. It doesn't help win drag races. It just creates smoother, better low end power and throttle response.
Honda didn't install a power valve on their ATV's becuase they felt it wasn't needed. They felt the counter-balanced design already delivered smooth power.
#30
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Pam I hate to burst your bubble but both the tecate 4 and LT250R where quite a bit faster than the Honder 250R in a drag race. A power valved motor is always the better choice than a non power valved version. Why do you think so many after market companies are now making power valved kits for the 250R? When CT compared their power valved version with their non power valved kit, it showed that the power valved version had a broader power band which results in less shifting and better acceleration. There is a reason why all modern dirt bike and high performance snowmachines utilize the power valve.
In fact the Tecate 4 accelerated so fast that it gave a banshee a good run for its money. Ask any Tecate 4 owner and they'll tell you the motor was no slug. In fact your the only person I have ever heard calling that engine a slug.
In fact the Tecate 4 accelerated so fast that it gave a banshee a good run for its money. Ask any Tecate 4 owner and they'll tell you the motor was no slug. In fact your the only person I have ever heard calling that engine a slug.