500 exc will not take throttle
- Thread starter drandy
- Start date
Any more background? Is this a new-to-you bike or had it a while? When was the last time it ran good (summer or earlier this winter)? Did it abruptly start doing this or slowly get worse? Did it begin after making a bunch of mods? Or maybe after maintenance (that could have broke something unrelated to the work being done or perhaps been done incorrectly)? That insight would be helpful.
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Check the wire harness where it goes from the frame up to the handlebars near the R/H radiator. Probably a broken wire in there where it flexes all the time. Sounds exactly the same as what my 14 500 EXC was doing.
Did this happen when you took it out of storage? Clogged injectors, low fuel pressure? Seems like a lean condition.
Ive seen the fuel regulators go bad and run at 25psi instead of 50. There is some place that's sells the regulator by itself (not ktm) but Can't remember where i got it. Easy to check though just hose clamp an air pressure gage on the line wherever convenient and click the start button a few times to prime.
Drandy,
Listen to this tip. Have heard about this too often. Never had issues with my 2013 Husaberg 501 (ktm 500) but read about this often enough to keep it in the back of my mind as something to check had i ever encountered an issue.
I wrote a post on common KTM cap problems last winter. Riding in the snow and brush, if the drain hole in the spark plug cap cavity in the head plugs, then when you park it in a warm garage, water collects in this cap well, floods your cap with water, then drains out over the week, but the cap gets rusty and you will have intermittent starting, runs great for 15 minutes then goes to craping. Put in a new plug, runs great ofr 1/2 hour then you can't start it. Must take the cap apart to see the problem. New cap and used compressed air to clean out the cavity and drain hole. KTM uses a proprietary plug cap made by NGK and you won't likie KTM price, but upon careful reading of the NGK catalog they have the correct cap. Nobody on ebay or Amazon identifies that this cap as a KTM replacement, but its the right angle, correct resistance, correct for stud head plugs. Search for the last years thread if the cap is your problem, I posted the NGK correct cap number.
I had intermittent idling problems last season that lined up with Catsledman's post, but not so much like you're describing. I am not saying a thing to undercut his post, that's a legitimate problem.
My ECU (PR2) was a little lean on the bottom, and exhibited a similar issue to what you're describing if I was using less than a quarter throttle. Bumped it a little richer and that went away. So the point of this rambling is that I'd check the plug and cap, and I'd check anything related to fuel supply, the easiest things first, which you already have a head start on.
My ECU (PR2) was a little lean on the bottom, and exhibited a similar issue to what you're describing if I was using less than a quarter throttle. Bumped it a little richer and that went away. So the point of this rambling is that I'd check the plug and cap, and I'd check anything related to fuel supply, the easiest things first, which you already have a head start on.
checked all the wires look fine. where do I go now.It will idle for about 30 seconds then die. When I try to give it throttle it back fires and pops but will take some throttle but not enough to go anywhere. it swells like it is running really rich. It does have the mild to wild switch on it.
Update I have replaced the fuel pump check all the wires everything looks fine it will idle for about 30 seconds then died I can't get it to take throttle but it pops and backfires and it does not have enough power to even move the bike anywhere smells real rich
REDID THE BATTERY GROUND WIRE?
TOOK THE PLUG CAP APART?
NEW SPARK PLUG?
Checked clean ground to frame on your coil?
Got another coil, any will work, try that?
HAVE YOU RUN IT ON THE SNOW THIS YEAR ? THEN NEXT RIDE IT WENT TO HELL ?
Rich and won't take throttle leads me to think for sure spark issue
TOOK THE PLUG CAP APART?
NEW SPARK PLUG?
Checked clean ground to frame on your coil?
Got another coil, any will work, try that?
HAVE YOU RUN IT ON THE SNOW THIS YEAR ? THEN NEXT RIDE IT WENT TO HELL ?
Rich and won't take throttle leads me to think for sure spark issue
Did you check for spark when you replaced the plug? Last year I had a bad connection (loose and corroded) where the spark plug wire "threads" into the plug cap which caused a similar issue. I had to cut the wire back to get clean wire and re-attach the cap.
I messed with it all day yesterday. I checked the valves. Did a leak down test. Everything was fine. THe last thing I did was change the fuel injector and that was it runs great now. Thanks for all the help and advise it was greatly appreciated. I now have a used fuel pump that is good if anyone would like to buy it,
How was the in tank fuel filter? Mine was black and really plugged up. Looked like pipe dope anti seize. Bag filter on tank inlet clean , hose filter after tank clean. Think pump was in process of dying. Best bike.com sells a better pump/filter in my opinion.
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