2017 500EXC-F. Something's wrong

[Stemmemx15]

Hey!,

So let me start off by telling you about the bike so it's easier to understand what may be wrong. The bike is brand new, bought it in march , I Desmogged it, put a PMB end cap on it, installed the "Best Dual Sport" fuel rail in it, and other then that it's stock. It has 1,500 miles on it and 44.5 hours. The oil has been changed 3 times now and the air filter Is cleaned every other ride. 

 

NOW! Yesterday I was out riding with my family (a very dusty day) and it started coughing mid throttle, so I Let off and it idled, I went to hit the gas and it coughed and gave out and then opened right up like nothing happened. Then about an hour later it coughed a couple times and seemed like it was about to die  but I gave it throttle and it took off. Another half an hour of riding passes and mid throttle in 5th or 6th gear it  coughs, I tried giving it gas then it coughed even more (like how a dirty gunky carburetor would feel when you get up in speed) and after a last attempt to give it a crack of throttle and keep going, it just shuts off in which the engine light and the gas light came on.

 

So I get off my bike and I check my oil which was perfect, my air filter that definitely wasn't dirty enough to cause that big of a performance issue, and ofcourse my gas which I was at 3/4 of a tank. Without turning the key off and then turning it back on again, it will not make a single sound when you go to push the electric start button, but when you turn the key off and back on, it then starts. After I start it and take off, I continue down the road about 5 miles and it does the same thing except this time only the check engine light is on. This last time it died was identical to the previous explained scenario. Out of frustration towards a $12,000 bike that should be running tip top condition, I start it and completely open the throttle hitting the rev limiter. For the next 30 minutes it didn't die sputter or cough at all. Since then i haven't ridden it and don't plan on it until I find out what it is or was. Something that maybe worth mentioning, i have not tuned this bike since I've replaced the fuel rail, desmogged it, and installed a new end cap, and the speeds that day ranged anywhere from 45mph-70mph. The only  time it died was when I was around 45-55mph

[soldmyxr]

At only 4 hours, I had similar intermittent symptoms and it turned out to be a bad fuel pump.  Mine just got harder and harder to start and would stall at every stop, got to the point where it wouldn't start at all.. You're also fairly lean with those mods and no tuning, but I doubt that would cause an internal engine problem at only 44 hours.

[xrbrp]

Did you check your in line fuel filter? Maybe it is plugged a bit. Slavens has a video about it suggests you carry one on the bike as it can be problematic. You should have an extra when you got the bike along with the throttle cam 

Edited July 30, 2017 by xrbrp

[Spud786]

Yeah other than inline fuel filter, I lay odds with the fuel pump or crack in the main tank fuel filter, its plastic and under pressure, and can spilt at the seams. Turn the fuel pump on and look in the tank , swirling or bubbles.

tends to happen most on new bikes, cause filter comes defective.

[xrbrp]

25 minutes ago, Spud786 said:

Yeah other than inline fuel filter, I lay odds with the fuel pump or crack in the main tank fuel filter, its plastic and under pressure, and can spilt at the seams. Turn the fuel pump on and look in the tank , swirling or bubbles.

tends to happen most on new bikes, cause filter comes defective.

 do you look when the bike is running or off? 

[Spud786]

3 minutes ago, xrbrp said:

 do you look when the bike is running or off? 

OFF, just get the fuel pump to turn on

[xrbrp]

3 minutes ago, Spud786 said:

OFF, just get the fuel pump to turn on

Thanks Spud. I just checked mine with the key on and no bubbles or swirl. But then fired it up and Katy bar the door that stuff was bouncing around like a cat with a hot foot

[Stemmemx15]

1 hour ago, jeanluconze said:

At only 4 hours, I had similar intermittent symptoms and it turned out to be a bad fuel pump.  Mine just got harder and harder to start and would stall at every stop, got to the point where it wouldn't start at all.. You're also fairly lean with those mods and no tuning, but I doubt that would cause an internal engine problem at only 44 hours.

Okay awesome I'll definitely check that out. It had me worried that my bike has already taken a turn for the worse 

45 minutes ago, xrbrp said:

Did you check your in line fuel filter? Maybe it is plugged a bit. Slavens has a video about it suggests you carry one on the bike as it can be problematic. You should have an extra when you got the bike along with the throttle cam 

I'll take a look at this before I think to purchase a new fuel pump. Thank you!

[Stemmemx15]

Thank you all for the help! I really appreciate it, after work I'll go home and do all of these tests and see if I can diagnose the problem and shoot you guys an update. Thank you again everyone 

[Spud786]

1 minute ago, xrbrp said:

Thanks Spud. I just checked mine with the key on and no bubbles or swirl. But then fired it up and Katy bar the door that stuff was bouncing around like a cat with a hot foot

I didn't recognize this was also with the new vortex.    I'd do that reset procedure before continuing, with positive cable disconnected for a few minutes first. The plug battery back in , and do the proper vortex set up procedure.

 

[Stemmemx15]

Hey everyone so I checked the fuel pump (No bubbles and seems to be running fine, I hear the fuel pump start up when I turn the key and nothing seems to be out of place), I checked the inline fuel filter (I didn't see one grain of dirt in it but I blew it out with an air can and put it back in) so i'm completely confused on WHAT it could be. After spending $12,000 on a bike you'd expect not to have any problems a few months later.

 

So yesterday after talking to one of my dads friends who's pretty savvy on engines he says it sounds like bad gas.... That's a good guess and all but my dad who has a 2013 500exc, and my brother who has the same exact bike as me, both filled up at the same exact gas station at the same exact time so for their bikes to not have ONE hiccup is very strange to me to diagnose my bike as having bad gas. So just to humor me, does anyone know the side affects of bad gas (not old gas) bad gas straight from the pump, would have on a fuel injected bike? Thanks again guys! I hope no one else has to deal with this because right now i'm regretting switching from Honda lol 

[travertt]

On July 30, 2017 at 2:05 PM, Spud786 said:

I didn't recognize this was also with the new vortex.    

I can't see where the OP said anything about a Vortex.

[Spud786]

14 minutes ago, travertt said:

I can't see where the OP said anything about a Vortex.

You're right , I got confused. It wasnt XRBrb who started the thread.

[Spud786]

Have you checked , that the battery cables are tight?

[Stemmemx15]

12 minutes ago, Spud786 said:

Have you checked , that the battery cables are tight?

Yes I checked the battery cables and also tightened them just to be sure

[sirthumpalot]

I've had bad gas in my truck, got about a gallon of water and rust along with my 15 gallons of fuel. That was a mess to clean up..  The symptoms would make sense for a little water or junk in the fuel, however I would expect that to clog up the tiny inline fuel filter pretty quickly if junk in the gas were the problem.  It almost sounds electrical.  See if you can figure out if it happens more often when the bike is hot, and rectifies itself as the bike cools down.  If yes, then that might indicate a stator or coil going bad.  Also double check your kill switch, the spark plug wire and cap, etc..  It might be that you've got a small crack in a wire or a bad connection, and you revving the bike just vibrated things back into a better position, until they vibrated back to a bad position later.  

[Stemmemx15]

Just now, sirthumpalot said:

I've had bad gas in my truck, got about a gallon of water and rust along with my 15 gallons of fuel. That was a mess to clean up..  The symptoms would make sense for a little water or junk in the fuel, however I would expect that to clog up the tiny inline fuel filter pretty quickly if junk in the gas were the problem.  It almost sounds electrical.  See if you can figure out if it happens more often when the bike is hot, and rectifies itself as the bike cools down.  If yes, then that might indicate a stator or coil going bad.  Also double check your kill switch, the spark plug wire and cap, etc..  It might be that you've got a small crack in a wire or a bad connection, and you revving the bike just vibrated things back into a better position, until they vibrated back to a bad position later.  

I'll go through it and check all of the electrical connections, hopefully less than more so I can diagnose it soon lol. Thank you for the information I'll keep everyone updated JUST in case (knocks on wood) someone runs into a similar issue. Thank you again! 

[Dansmith1965]

After spending $12,000 on a bike you'd expect not to have any problems a few months later.

Your bike comes with a 6 month warranty, if it's only been a few months since you purchased it take it back to the dealer.

[Stemmemx15]

3 minutes ago, Deepseadan said:

Your bike comes with a 6 month warranty, if it's only been a few months since you purchased it take it back to the dealer.

I DeSmogged it so the warranty is no good, unless I was told wrong? 

[Dansmith1965]

I DeSmogged it so the warranty is no good, unless I was told wrong? 

Throw the smog stuff back on and they'll never know the difference.