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Keyboard know-it-alls in full backpedal mode after objective testing shows they're F.O.S.

LOL!

Still a silly idea to me......

If anything it "may" help with intake restriction, that could be easily fixed with a different free flowing filter. IMO the fan isn't doing squat.

Doesn't the K&N filter like add 2hp over stock? :excuseme:

I wonder if anyone could dyno a 250f with out an air filter and post the results?

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Good call Mutu. That's what I'm talking about. Where is the data? I would think if you are forming a company you would want to immediately show your results on an independant dyno as a at least proof of concept. I haven't even see that part yet.

Again, this is not to say it doesn't work, because i personally have not tested it or seen the data, but the science certainly doesn't hold water in my mind.... but I have small mind so if I'm really over looking something some one please educate me, however not beyond my intelligence because my head might explode.

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In theory, this wouldnt work by any means. You can force more air into the engine at 14psi (sea level) than what is in the air box and available. Turbochargers and superchargers have housings that allow them to compress the air going into the engine, which allso it to take more in, since its more air going in with the same volume. Until someone develops a small supercharger or turbo on a Fuel Injected bike, its really not going to do any good, since the carb in a dirtbike would be hard pressed to deal with the boost of a charger, since it can change.

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Until someone develops a small supercharger or turbo on a Fuel Injected bike, its really not going to do any good, since the carb in a dirtbike would be hard pressed to deal with the boost of a charger, since it can change.

Turbos have been used in "blow-through" configuration for many years on carb'd engines, BUT, for it to work properly, the bowl vents and any other air passages in the carb that are vented to ambient must be relocated to terminate in the bonnet and be maintained at the same pressure as the air entering the carb throat, but also positioned so that the airflow through the throat does not produce a scavenging effect. In this application, on the "clean" side of the air filter inside the airbox.

Any other location will cause variations in mixture as the boost (excuse me, ASSIST) levels rise and fall with the variations in the fan RPM.

Simple ram-air systems produce measurable gains on carb'd autos because the carb bowl vents are located inside of the air cleaner housing. This maintains a constant RELATIVE pressure on the metering jets.

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This is gonna be one of those never ending threads, in theory it wont work, according to kelstr it will, I dont want any more power in my bike anyways

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Just remember... The PowerNow people never posted any dyno graphs, there were a lot of skeptics when it first came out yet they have made a lot of $$ off of that thing... and the people who have tried them can tell the difference, nothing major but it does help the bottom end, not good for top end riders though...

However, I must point out that "physically" speaking, the PowerNow theory for increasing air velocity makes sense. As for this project, physically, it doesn't make sense, yet an independent tester that WE have asked way back when to test this product and give us the feedback (i.e. Kelstr, one of our trusted members, motohead guru type) have verified that it DOES work/help the mid & top end. Dyno graphs will help show the gains (if any) and add some merits to this product, but obviously the jury is still out on this product until we see some "hard" facts/graphs instead of seat of the pants opinions... :excuseme:

The PowerNow product was the same way, no dynos, but a lot of seat of the pants claims that it worked and that company went on to sell a lot of those things. Now we have other companies COPYING that PowerNow blade so that they can get in on the $$...

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One thing that I have a question on.... and keep in mind that I've done dyno runs, but never on a bike...

Why are the runs limited to 3 seconds, thus, only seeing the effect of the 2.5 sec AP squirt? It would seem that it would take more than 3 seconds for the engine to reach redline in 4th gear.

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The runs take about 4-5 seconds in fourth gear to reach redline. That's where I run into a lean problem on the dyno because my a/p is only good for about 2.5 seconds.

On the track this isn't a problem because I am really never in the same gear for more than 3 seconds. The dyno that I used each time was set up for four wheelers but it had a bike attachment. I don't know dyno's that much but does it need to be recalubrated for bikes? As far as wheel resistance or is all the same ?

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That is a big problem for non-track usage... and since this is not AMA-legal, it is something that should be salable primarily to trail riders, who definitely spend more than 3 seconds in one gear.

You can't use only the AP squirt as your primary jetting... it's just not right and will never give consistent, or accurate results.

If the bike is going lean, it's not jetted properly, period.

If it goes rich with "proper" jetting because of the AP, then the AP is too fat.

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The a/p is not my main source of my jetting. The bike responds very well to other changes in the circuits. I have had it jetted to the dyno just to go to the track all excited to ride and then it runs like a terd becuase all of the extra fuel. Trust me I have been through this a time or two. I think that this is more common than you think with jetting bikes to dyno's. I think dyno's are a good tool for setting a baseline for jetting but once you get to the track sometimes you might have to do some tweaking around. I just don't see how you can tell me what I can and can't do with you not having any experience with this product. If it takes more reviews from other people to win everyones trust then so be it! I just hope my pocket book can handle it!

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The a/p is not my main source of my jetting. The bike responds very well to other changes in the circuits. I have had it jetted to the dyno just to go to the track all excited to ride and then it runs like a terd becuase all of the extra fuel. Trust me I have been through this a time or two. I think that this is more common than you think with jetting bikes to dyno's. I think dyno's are a good tool for setting a baseline for jetting but once you get to the track sometimes you might have to do some tweaking around. I just don't see how you can tell me what I can and can't do with you not having any experience with this product. If it takes more reviews from other people to win everyones trust then so be it! I just hope my pocket book can handle it!

Scooter, Wheelsup is right, I stay in one gear a lot longer than 3 seconds on the track - sometime I only use 3rd gear for most of the loop. I also do a lot of "roll ons" and not quick blips of the throttle so in my case, the AP may not be "pumping" too often so how will your product handle "roll ons"? Trail riders won't be blipping their throttle to WOT all that much either (at least not for 3 seconds straight), this is my experience with trail riding while trying to dodge trees in tight single tracks... :excuseme:

Trail riders want more low to mid anyway, not mid to top where your product apparently shines...

I do admire you for keeping up with your endeavors and I hope your company will do well :thumbsup:

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it is funny to see so many people hung up over an idea, when they think sitting at their computer there is no way this idea will work. ( when these same people have never tried this idea , or ever built a blow through period )

and even funnier yet, 99% of these armchair riders here have never even built mod motors on a daily basis, worked a flow bench day in and day out, ported heads and had to re-weld when you went into coolant , ran 40 dyno runs , then went to the track to compair ------( and generally the dyno runs do not even come close to what it will or wont do on the track-----) ( real world is more of a true tell if you are going forward or not.

the dyno is just a tool like your tape measure, -----and to make matters worse no two dynos read alike, ----they can be way off . ( the three i use are so different , as well as everybodys elses :bonk: )

and you have no wind resistance , nor air screwing up your still air area in the dead portion of you are box, no super deep loam right at the apex pulling badly at both wheels while your pinned and still dragging the brakes to stay in the 10" deep rut :eek: .

everybody thinks a dyno is the be all end all , but they could not be more wrong.

many times i will come up with a combination on a motor that will show 2 hp less on the dyno---i will try several different lobe centers and jetting to no avail :cry: ( on paper the combo looked really good in one area ---but the dyno showed different :excuseme: ) , but you go to the track and that dam bike beats the other 250's up the hill at glen helen and will make the huge tripple step up at millvill where my other motors with 2 more hp will dam neer not .

so yes i will use a dyno for what it is , "a tool" and thats all -----it is not the all mighty answer that people think it is.

and the jetting you end up with on the dyno could not be more different to what you actually end up using on the track that let the thing just rip , -------then you come back from the track and re-run it on the dyno and you are way off on ( those big numbers you first tweaked and got on the dyno ),

thats why all the tuning goes on at the track 3 days before a national , ---that because it doesent work on the dyno , its been this way for ever .

so sure i could have ran this thing on a dyno and tweaked the hell out of the jetting ----leaned it down like all hell to get it to really make some strong numbers , ( thats what the pipe makers do ------i know we have all got taken on a pipe claim----i did not want that for you tt guys )

but i wanted to give a real world take on it , this is where you run your bike ,--not on a dyno :crazy:

and i am not saying this just because of this product, ---i am trying to give you guys alittle insight into what it takes and what "tools" will do what.

there is alot more seat time , trial and error ( with more on the error side ) going on than one would think :cheers:

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Av, I haven't encountered any problems with slow rollons with our product at the track. You can hold the throttle at the same position at mid throttle and the bike acts just fine. It dosen't rev up or speed up like it was leaning out.

There will be no problems with trail riders.:thumbsup:

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To build a bit on what Kelstr said, a dyno is part of the tool box. What a dyno does for me is shows me the curves. I could careless about horsepower or torque NUMBERS, I care about the curves. It's very easy to manipulate the numbers. Change the drag coefficient for example and all your numbers will change. To me a dyno is a good measure and an important measure of curve changes that occur when you do a modification. It is also a very good and fairly cheap marketing tool. I get worried when a product doesn't show one. Does this mean the product doesn't work? Nope, it simply makes me more skeptical.

My method is far from the gearhead method that Kelstr might use. I have a small do-it-yourself kind of dyno that I use to measure curves. I measure that every motor type mod I make. I see what happens to the curves. I also use my A/F Meter to make sure I get everything jetting correct. Once I see what I have done to the curve from a baseline, I go ahead and switch to the ass dyno.

I respect Kelstr's expertise in this however, I am far from an armchair rider but not as far along as some one like Kelstr or AV. I have asked for an explanation of WHY this works with some math around it and I still haven't gotten it. How do you avoid double carburation or blow-back? How does this work so well on a stock motor? What kind of gains can be expected? What kind of curve changes will there be? All of this is yet to be answered objectively for anyone. So I have said it before and I will say it again, the jury is still out. I just don't see how it will work and no one has really sat down to school me and prove it to me.

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Yo been following the thread since the beggining the idea sounds great , all though doesnt seem plausable, in theory if it worked how would the device hold up to the rigors of MX Use as well as Enduro ?:excuseme:

If we are going to try wacked Bolt on devices lets go the whole nine and bolt on a sneaky Pete NOS System if it works I RATE IT WOULD CLEEEEEN My Pipes :eek: !!! imagine an insane rush of HP :eek: till then i rate i will wait till YAMAHA launches a Yamaha WR/YZ250 with a factory Charger bolted to it.:bonk:

for the sake of a steroid driven PC Fan and grenade 2-3 K worth of motor not an option but hey thats just my 2 cents:ride:

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for the sake of a steroid driven PC Fan and grenade 2-3 K worth of motor not an option but hey thats just my 2 cents:ride:

It ain't gonna' grenade the motor unless your jetting is already pretty bad to begin with. Even if it DOES work as claimed as an "assist", it should not impact the mixture anywhere near as much as a pipe... and there are a TON of people running stock jetting on new pipes. they may not be getting peak performance, but they aren't smoking their engines either.

You do have a good point about long-term, and only testing will tell how long the fan will last. Basic "muffin" fans aren't designed for a dirty environment, but even so, traffic signal cabinet fans typically last 10 years or better running 8-10 hours a day and they can get packed with dust.

I think a shot of "canned air" every time the filter is cleaned/changed will keep the fan alive.

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mmmm. true , good info , you rekon it is worth a try or not ? are you gonna give it a try?

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mmmm. true , good info , you rekon it is worth a try or not ? are you gonna give it a try?

Nope. I'm very happy with my WR and it's current mods. The only time it's let me down is on hillclimbs, and then it's been my nads rather than the bike that has let me down.

If I ever decide I want more power, I'm going to want more than any mod will provide and will upgrade to a 450.

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Yo WheelsUp i rekon ur right i am supa happy with my 07 WR its too good i just bolted a YZ Header & Can & JD Jet Kit to it and it has made an unreal difference like Bottled Rage i tell you. possibly the best mod i have done so far.

any other mods you recomend ?

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I think the Athena folks have a mod that you'd like... ;)

But seriously, once the free mods and exhaust are done, I'd get into the suspension (which should be done first anyway, but no one seems to do it in that order since it's confusing and not nearly as cool as a shiny new pipe). :bonk:

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