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GREAT INFO ........ that would be cool if you get a graph with a bone stock LTR, TRX, YFZ and a KFX all on the same sheet and all runs from the same dyno. That would be SIK.


FUELATV
 

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Here it is............[attachment=250:Stock_08_KFX450.jpg][/b]
Kind of worthless if you didn't dyno another 450 so we would have something to compare it to (using the same dyno with the same conditions).
 

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Discussion Starter · #6 ·
As per some requests.....Here is an overlay of a YFZ (blue), TRX (red), LTR (brown), and KFX (green). Runs were not done on the same day but conditions were within 10 deg and 5% humidity. All have the SAE correction factor as well.

[attachment=294:STOCK_450_QUADS.jpg]
 

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Thanks for the graphs, looks great. It looks like the KFX and LT-R have a similar powerband. The KFX with a little more over rev. Do you have A/F graphs for all 4? On the LT-R what does with QC mean? Can't wait for the graphs with a controller, LRD pipe and lid removed.

Thanks again for the graphs.

-Bill
 

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Thanks for the graphs, looks great. It looks like the KFX and LT-R have a similar powerband. The KFX with a little more over rev. Do you have A/F graphs for all 4? On the LT-R what does with QC mean? Can't wait for the graphs with a controller, LRD pipe and lid removed.

Thanks again for the graphs.

-Bill[/b]
That dyno looks to be very generous. Seen many many of all the 450's bone stock around the mid 30's for HP. Heck the YFZ 450 has more RWHP then it's rated at the crank and the KFX is only loosing 3hp from crank to wheels. But whatever the dyno is, it does show that all the 450's are pretty close stock. But the biggest thing, what will come out of the KFX once modded. They didn't have a very good showing on there 1st MX race. In fact there was a pic floating around of the start, and both KFX were last by a big margin hitting the first corner.
 

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That dyno looks to be very generous. Seen many many of all the 450's bone stock around the mid 30's for HP. Heck the YFZ 450 has more RWHP then it's rated at the crank and the KFX is only loosing 3hp from crank to wheels. But whatever the dyno is, it does show that all the 450's are pretty close stock. But the biggest thing, what will come out of the KFX once modded. They didn't have a very good showing on there 1st MX race. In fact there was a pic floating around of the start, and both KFX were last by a big margin hitting the first corner.[/b]
Thanks for the reply. It looks like LRD and Fuel will have dyno numbers with pipe, pcIII and airbox eliminator soon.
 

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Wouldn't you think that the FI on the kfx should take nicely to any mods?, but i'm not for sure.
 

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The KFX and LT-R are a open loop fuel injection systems. Where as a street bike or automobile are closed loop systems. Closed loop systems have an O2 sensor in the exhausts and a open loop system does not. So a fuel controller in a closed loop system will change fuel delivery based on A/F ratio read by the O2 sensor. You need to dyno tune the KFX and LT-R using an A/F sensor with the bike on a dyno. You adjust A/F ration with you controller and various RPMs and then program it into your fuel controller.

I hoped this helped with the above question.

-Bill
 

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Quad runner is correct. to add to what he is saying, cars use several different metering devices to adjust the A/F mix to be the most efficient(ie O2 sensor, MAF, MAP, IAC Temp, and so on) ATV are a primitive/basic fuel injection designed to save on space and weight. Therefor the fuel controller is going to be preset to dump a certain amount of fuel in relation to the TPS and other readings. That setting will be limited to certain parameters or amount of adjustments it can make. Once the engine has been modified, it will be out of the stock parameters of adjustment and will need modified itself. I hope I didnt confuse anyone anymore. I dont have alot of small engine modification experience, all of my experience is based on cars, but all 4 stroke engines are basically the same. All you need is air/fuel, and spark.
 

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A couple things. It does not matter if this dyno is high or low compared to any other dyno, that is a worthless comparison. What everyone needs to be looking at at the curves of each atv on the SAME dyno. You can compare those numbers make some decent judgements from it. Thank you for posting the comparison graph.

Secondly, I hate to see the KFX getting judged so quickly on the MX track. The LTR and YFZ a couple years of a head start on the R&D compared to the KFX. I would hope the KFX could not compete yet, if it could at this early stage of R&D, imagine what it would do after a couple years. Anotherwards, give it some time to catch up. The same engine in the 2 wheelers is proving to be a big force in comparison to the others!

PDR will be doing some dyno testing as well here soon. We will begin working with Fuel Customs for a superb intake within the month. We will be developing some engine packages which will include porting, cams, and pistons as soon as the intake is finished. The ball is rolling guys.

PDR
 

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A couple things. It does not matter if this dyno is high or low compared to any other dyno, that is a worthless comparison. What everyone needs to be looking at at the curves of each atv on the SAME dyno. You can compare those numbers make some decent judgements from it. Thank you for posting the comparison graph.

Secondly, I hate to see the KFX getting judged so quickly on the MX track. The LTR and YFZ a couple years of a head start on the R&D compared to the KFX. I would hope the KFX could not compete yet, if it could at this early stage of R&D, imagine what it would do after a couple years. Anotherwards, give it some time to catch up. The same engine in the 2 wheelers is proving to be a big force in comparison to the others!

PDR will be doing some dyno testing as well here soon. We will begin working with Fuel Customs for a superb intake within the month. We will be developing some engine packages which will include porting, cams, and pistons as soon as the intake is finished. The ball is rolling guys.

PDR[/b]
Sounds great, please keep us updated.
 
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