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2017 500 EXC-F Quick Throttle = Dead bike

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So as title states, I give my 500exc-f a quick flick of the wrist and it dies. I can make my bike die by giving it TOO much throttle. I bought the KTMandHusky fuel rail mod and am installing it in a few days. I'm at about 2500ft above sea level. Bike has 20 hours, filter is green and clean. Only running premium gas. Will this fix my issue? I'm almost positive it is a "flame out" Oddly enough this started happening around 10 hours of ride time. Bought the bike new and it had zero issues.  Bike has no mods 100% factory. Thanks for any help!

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You'll be a good test, for the CLAIM!

so make no other adjustments till you try the rail(and post the results),  but tps and mapping adjustments should actually cure.

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Letting this bike re-acclimate might help as well. You never know the dealer might not have done it.

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my new 500 did the same at sea level, TPS adjust and new ECU map fixed the issue

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Mine did that after a reflash.  TPS was too rich, backed it down and all was well.  

Fuel rail should have zero effect on your issue.  The pump delivers a stream, the injector sprays a mist, gas is a very low viscosity fluid and has no problem making a 90 degree bend at the flow rate required by the injectors at WOT.  

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Thanks for all the info guys. Installed today and have noticed zero difference. So much for the cheap fix ;) Guess I should have popped in here first before the purchase!

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Do you have a fairly fast idle , it may be your idle dropped some since new. Outside of that, you can try upping the tps . Previously exc's, had a separate idle circuit type throttle body, so really simple adjustment. The 17 changed to a more standard idle design, and the idle itself , will change the tps settings cause it moves the throttle plate. So good to have some base before you begin moving the tps  , so worse comes to worse you can get it back to where it was.

So start with the idle, then find out where your tps setting is. If You haven't opened the intake and exhaust up, you should be able to get away with tps adjustment ,alone.

Edited by Spud786

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Increasing my idle speed helped a bit. Keeps it from "flaming out" but damn if this doesn't feel like a poorly tuned carb bike....I'm guessing a whole new tune and throwing money will fix it. I've done an oil change on the bike and that's it. Within 20 hours it went from instant power to choppy laggy power. Zero change in performance with KtmAndHusky fuel rail honestly feel like this thing is a joke. At least their wheel weight changed the 60+ mph death wobble into a more manageable death sway/wobble.

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Get a balancing stand, then you'll have 2 finger post 100 mph stability.

 

If still seeing a major difference with engine performance since new, then something is wrong with fueling system, more than likely.  turn your fuel pump on and look into the tank, fuel should be very stable. might have a fuel leak in the pump filter or something ,that will cause flakely action.

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mine is dialed in so as not to flame out ever ! I ride trials style and a flame out will ruin your day also it always helps to alter the gearing . most flame outs are a lean condition

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I'm going to agree with Spud here, that if this was not an issue initially and is now suddenly an issue then the problem is not an adjustment, the problem is that something is wrong.  When you whack the throttle open on a 4-stroke, the motor needs a big shot of fuel to keep running.  On a carburetor this is done with an accelerator pump, on an FI engine the FI system knows to give it more fuel for a moment.  If you have a clogged filter, or a dirty injector, low fuel pressure caused by a crack in the in-tank pump or filter, etc.. anything that can limit normal fuel flow, then that might be the cause.  Start with the easy stuff; new in-line fuel filter, even if it looks clean, and look in the tank when you turn the bike on and see if there is fuel swirling around.  Swirling fuel would indicate a split in the pump or filter.  

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