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Discussion Starter #1
Hi everyone. I'm new here and new all together to the kfx450r. Something about it just stood out to me so I just went for it and im glad I did. 08 kfx450r dmc slip on, air box lid off with unifilter, HID lights. Runs great for the most part but in higher rpms its getting a little bit of bog. I've tried searching the forum for an answer but not sure on cause. I'm guessing its because of the exhaust and not having a efi controller maybe? Also my HIDs back shine like a mofo on my polished tag bumper. Any suggestions would be great. With a few more add ons im sure she'll be up to par. Thanks.
 

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Welcome to the Forum...!!!

you only need a fuel controller when you replace your OEM intake tube...see pic,

OEM circled in Pic. more air=more fuel...

If it's new and still under warranty have your dealership do a fuel pressure test & check the valve clearance for the symptoms of it bogging in the higher RPMs...

The HID glare off your bumper, you can put Black tape on the back side to prevent it from reflecting back into your eyes so you don't damage the polish finish...
 

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Discussion Starter #3
It's not under warranty. I sold an 86 lt250r and bought the kfx. Could it have anything to do with the tps? I really have no clue about 4 strokes yet especially fuel injected lol.
 

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It's not under warranty. I sold an 86 lt250r and bought the kfx. Could it have anything to do with the tps? I really have no clue about 4 strokes yet especially fuel injected lol.
Did you buy it used...?? if yes..start simple put in a new spark plug NGK CPR8EB-9 and run some injector cleaner in your fuel, I recommend Seafoam fuel additive...http://www.ebay.com/itm/Sea-Foam-Mo...tomotive_Services&hash=item2a20aa56b0&vxp=mtr

It could be the TPS if out of range...0.58~0.62 volts DC at Idle & 3.7~4.1 volts at WOT...if in range

then check the fuel pressure, 43psi constant 1800~10,500 RPMs...if good,

Check the valve clearance intake 0.10~0.15mm Exhaust 0.17~0.23mm..
 

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Mine was doing that also and it turned out to be the fuel pump if I recall right it's supposed to put out 46-49 psi and I was getting 44 psi I hope it's not that for you cause a new pump is around $400
 

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Discussion Starter #6
Yes it was used and the guy became shady and wouldn't reply back after it died the first night but I swapoed the stock ecu w a race ecu and found that the ignition relay wasn't getting a good connection but got that fixed. Thanks so much guys. I'll start with the new spark plug and injector cleaner. If thats not it I'll check the tps then valves and then fuel pressure. Praying its not the fuel pump.
 

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welcome to the forum! this will be hands down the happiest forum you have ever been on!! something about that lime green color makes us all CRAZY!!
 
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