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Vapor lock on 2010 390??

I should be riding on the beautiful but I'm not because my bike won't run!! :cuss: After my last ride, last wekend, I washed the bike, rode it around the neighborhood to "blow dry it", wiped off the remaining water drops, and put it in the garage. This morning, I loaded it on the trailer and was getting into my car. Then for some reason I figured I'd start it to make sure all is right. It's got a full tank of gas, and it fired right up. Then it died!!. :angry: It fires right up again, but then dies again. It just won't run. I can hear that the fuel pump is buzzing, but the bike won't idle. Sometimes it will idle poorly, but as soon as I touch the throttle it dies. After several tries, I'm able to "catch it" with the throttle, and it runs at about 1/2 throttle. But when I release the throttle, it sputters and dies. I increased the idle speed knob a few clicks, but that does not change anything. I fiddled with it for 15-20 minutes, but it just won't run. It seems like it's just not getting enough fuel pressure. My spark plug was new as of two rides ago. I don't have a fuel pressure gage, but my bet is that fuel pump is not putting out enough pressure. This pump was from my dealer's demo bike which had a few fewer hours on it than my bike.

On a side note, I really think I'm done with Husaberg. I'm going to lose a lot of money, but after pretty much losing one riding season, I need to get this POS fixed, and then I think I'm going to sell it. I've had so much down time on this expensive bike, that it's been nothing but a huge frustration. That combined with Husaberg evidently not giving a sheet, just makes this whole Berg experience WAY more trouble than it's worth.
 
Plugged injector ...?

Either way, I feel really sorry for you, JQ. Like you said, you should be riding.
sorry, man.

- ET
 
JohnnyQuest said:
On a side note, I really think I'm done with Husaberg. I'm going to lose a lot of money, but after pretty much losing one riding season, I need to get this POS fixed, and then I think I'm going to sell it. I've had so much down time on this expensive bike, that it's been nothing but a huge frustration. That combined with Husaberg evidently not giving a sheet, just makes this whole Berg experience WAY more trouble than it's worth.
Click to expand...

I understand your frustration and honestly It's crossed my mind also that maybe I should sell this now. If I was still racing, I would sell it in a second. I can't trust this bike to start cold or hot. Luckliy I like the bike and I'm not in a points race and I have the time to try and get the issues worked out.

I rode it today and it stopped twice for 30-40 minutes each time. It's annoying and very embrassing. Hopefully getting a new few pump will solve this issue. The bike runs great when it runs.
 
MrSmooth said:
JohnnyQuest said:
On a side note, I really think I'm done with Husaberg. I'm going to lose a lot of money, but after pretty much losing one riding season, I need to get this POS fixed, and then I think I'm going to sell it. I've had so much down time on this expensive bike, that it's been nothing but a huge frustration. That combined with Husaberg evidently not giving a sheet, just makes this whole Berg experience WAY more trouble than it's worth.
Click to expand...

I understand your frustration and honestly It's crossed my mind also that maybe I should sell this now. If I was still racing, I would sell it in a second. I can't trust this bike to start cold or hot. Luckliy I like the bike and I'm not in a points race and I have the time to try and get the issues worked out.

I rode it today and it stopped twice for 30-40 minutes each time. It's annoying and very embrassing. Hopefully getting a new few pump will solve this issue. The bike runs great when it runs.
Click to expand...
I really feel for you guys... :( I went through somewhat that kind of frustration with the cam/ADC and engine oil consumption issues on the '08 KTM 450 EXC-R. So I can sympathize with how you must feel.

I'm at 60+ hours and over a 1000 miles and have had my FE 390 through some pretty tough races and technical trail rides and it has never missed a beat. Hot, cold, muddy, wet, updside-down ... it just starts and goes. I just wish you could be having the same level of performance.

Best wishes, E-Ticket
 
Man, I've been depressed all day. I've been dealing with problems with this bike since early July. I've only had two good rides since then! I really thought the tank from my dealer's demo bike was going to be the end of my problems. But after two rides I'm having problems again. The good news is that now the bike has a constant problem so that should be easy for someone with the right instruments to diagnose. I will NEVER again buy any bike where the dealer is 4 hours away. There is a local KTM dealer. I'll call him tomorrow. Hopefully the fuel pressure gages and most of the diagnostic equipment are the same. How can Husaberg not show any concern? Are they really going to tell me that I shouldn't have bought one of their bikes because the nearest dealer is so far away? How can they just let us hang like this?

This afternoon I tried it again. It fires right up and runs for about 5 seconds. Then it just hacks a hairball and dies. It will restart, but again dies. I tried it about 4 times. It ran perfectly last weekend. It really seems like a fuel pressure/starvation problem, but how the heck does it go form running great to not running at all when the bike is sitting in the garage? I didn't check the filters, but my dealer checked them before he sent me the tank, so that can't be the problem.
 
clbuff said:
In my case I'd solve my problem! :cheers: today I went riding for a long tight single track in the woods and the 390 behave flawlessly, the engine starts every time I needed, so I think that the first and must upgrade it's to isolate the fuel tank from the heat to preserve the fuel pump life.
Click to expand...

I'm betting the fuel pump was the issue and heat sheilding may have helped but didn't solve the issue. I mean, the fuel pump doesn't run when hot and that's a flaw that needs to be fixed. Today, while waiting for the bike to start again (had the bike in the shade with the seat off and a cool breeze today) we would just walk over every 5-10 minutes and hit the start button. If the fuel pump didn't make a sound, no go. 5-10 minute later, hit it again. As soon as you finally hear the fuel pump spin up, it would start and run fine.

So, I see that clbuff has his fuel pump replaced and now the problem is gone. Yes, he insulated the tank and wrapped the exhaust but I've done that too with zero change. I also searched this thread for and I didn't find one person with a 2011 that has this issue. I saw one 09 but mostly 2010's.
 
JohnnyQuest said:
I should be riding on the beautiful but I'm not because my bike won't run!! :cuss: After my last ride, last wekend, I washed the bike, rode it around the neighborhood to "blow dry it", wiped off the remaining water drops, and put it in the garage. This morning, I loaded it on the trailer and was getting into my car. Then for some reason I figured I'd start it to make sure all is right. It's got a full tank of gas, and it fired right up. Then it died!!. :angry: It fires right up again, but then dies again. It just won't run. I can hear that the fuel pump is buzzing, but the bike won't idle. Sometimes it will idle poorly, but as soon as I touch the throttle it dies. After several tries, I'm able to "catch it" with the throttle, and it runs at about 1/2 throttle. But when I release the throttle, it sputters and dies. I increased the idle speed knob a few clicks, but that does not change anything. I fiddled with it for 15-20 minutes, but it just won't run. It seems like it's just not getting enough fuel pressure. My spark plug was new as of two rides ago. I don't have a fuel pressure gage, but my bet is that fuel pump is not putting out enough pressure. This pump was from my dealer's demo bike which had a few fewer hours on it than my bike.

On a side note, I really think I'm done with Husaberg. I'm going to lose a lot of money, but after pretty much losing one riding season, I need to get this POS fixed, and then I think I'm going to sell it. I've had so much down time on this expensive bike, that it's been nothing but a huge frustration. That combined with Husaberg evidently not giving a sheet, just makes this whole Berg experience WAY more trouble than it's worth.
Click to expand...

Stupid question.
when you have your cold start issue, have you tried removing the air filter? Any chance of over oiling it?
 
Thanks for the suggestion on the air filter. However, I didn't clean it after the last ride. I rode on a rock trail there was no dust, and the filter was not dirty. I just washed the bike, rode it abound the block, and put it away. Then one week later, it won't run.
 
MrSmooth said:
clbuff said:
In my case I'd solve my problem! :cheers: today I went riding for a long tight single track in the woods and the 390 behave flawlessly, the engine starts every time I needed, so I think that the first and must upgrade it's to isolate the fuel tank from the heat to preserve the fuel pump life.
Click to expand...

I'm betting the fuel pump was the issue and heat sheilding may have helped but didn't solve the issue. I mean, the fuel pump doesn't run when hot and that's a flaw that needs to be fixed. Today, while waiting for the bike to start again (had the bike in the shade with the seat off and a cool breeze today) we would just walk over every 5-10 minutes and hit the start button. If the fuel pump didn't make a sound, no go. 5-10 minute later, hit it again. As soon as you finally hear the fuel pump spin up, it would start and run fine.

So, I see that clbuff has his fuel pump replaced and now the problem is gone. Yes, he insulated the tank and wrapped the exhaust but I've done that too with zero change. I also searched this thread for and I didn't find one person with a 2011 that has this issue. I saw one 09 but mostly 2010's.
Click to expand...

Agree. I think the insulation is just a coincidence. Also, it seems that the bikes that are now having the problem ran great for ther first 20-30 hours (mine did). I wonder if any 2011s have that many hours on them. If the problem doesn't exist in the 2011 bikes, that would be encouraging and would indicate that they tweaked the design of the fuel pump. However, according the the parts manuals available on line for the 2011 bikes, the part number for the fuel pump is the same. If they changed it, I'd expect the number to be different. If you buy a "new" one how do you know if you are getting a new one if the part number is the same as the old one? If you search for the part number - 81207088011 - you'll see that not only do the 2011 'Bergs have the same pump but the 350 SX-F does as well.
 
JohnnyQuest said:
If you search for the part number - 81207088011 - you'll see that not only do the 2011 'Bergs have the same pump but the 350 SX-F does as well.
Click to expand...
Well that's disappointing I had hoped it was a different part number. The majority of them are obviously working well, but I think I have a lemon. Husaberg can make it right by taking my bike back and giving me a 2 Stroke 300 :cheers:
 
JohnnyQuest said:
Thanks for the suggestion on the air filter. However, I didn't clean it after the last ride. I rode on a rock trail there was no dust, and the filter was not dirty. I just washed the bike, rode it abound the block, and put it away. Then one week later, it won't run.
Click to expand...

Long shot - but maybe pull the air filter and make sure that you didn't get a puddle of water in the bottom of the air box? And while there - make sure that your fuel pump connector is fully connected?

Just trying to think of anything that might help .... - ET
 
I guess we'll have to wait for this to start happening on the KTM 350s before KTM gives it any attention.
 
Just a thought, guys, after reading this whole thread.

The fuel pump is fuel-cooled. It generates a good deal of heat of its own, being a compact, high-powered motor.

So if the fuel is anywhere near boiling, it probably will boil once it gets into the pump.

Once the fuel turns to vapor, the pump might even still be spinning but not making noise since it's not working against high pressure.

As mentioned earlier, the testing is done with fresh fuel, so that would explain why the pump seems fine on the test bench. And it may actually be fully functional under those conditions.

My Husa is carbureted, but in my FI vehicles I try not to run them near empty, especially on hot days, since there is inadequate fuel to cool the in-tank pump.

I think there's a good chance you're getting vapor lock in the pump, and that the fuel in the tank may be getting heated more by the pump itself than from nearby radiant heat.
 
".... I think there's a good chance you're getting vapor lock in the pump, and that the fuel in the tank may be getting heated more by the pump itself than from nearby radiant heat...."

Good point! Or it's all factors combined. Trapped heat under gas tank, low fuel level, fuel pump running hot, *cheap-**** fuel pump, etc., etc. ...

Best options (in order):
= Remove in-line, one-way valve from gas tank vent line
= Remove check ball in gas cap
= Competition fuel-injection mapping (to help engine run properly and cooler)
= Radiator fan (to help keep overall engine temperatures down)
= Reflective heat-liner on bottom of gas tank
= Heat-wrap on mid pipe *or* heat-resistant ceramic-coating on inside/outside of mid-pipe
= Heat-reflective tape/wrap on fuel line
= Less restrictive exhaust (but I personally feel this is a lesser issue)
= And lastly .... possibly the 70D Racing sub-frame fuel tank ... to help avoid the low-fuel/fuel-pump overheating issue ....?

It will be interesting to see if 2011/2012 gas tanks come with a refelective heat-covering on the bottom, eh?

E-Ticket
 
2011 570 doesn't have a reflective heat barrier under the tank from the factory.
 
While I ride in Florida and it get's hot, it doesn't ever get over 100F and lately it's been in the low 80's and low humidity. I would think Austrialia is a more harse climiate yet no one there has had this issue? We have crap for gas here but I do have a source for "recreational' NON-ETHANOL gas. Ethanol's boiling point is much lower than gas. I'm going to empty my tank tonight and fill it with the non-ethanol gas and ride Thursday. I'll post the results.

Has anyone had this issue with Ethanol free gas?
 
Mr. Smooth,

Actually my bike has 60 hours and it was running perfect until 57 working hours! I did not had tank insulation and exhaust insulation until now that I´d change the fuel pump, so what I think is that the high temperature in the fuel reduce the fuel pump life and thanks to the high temp it fails, so I replace the pump and to preserve it I´d installed the insulation in the tank and exhaust.
Since new my bike is riding in the same conditions (tight single track) with high temps conditions and it never fails (57 working hours) until now.
 
Vapor Lock @ high temp, not enouhg head pressure for the pump ? One could try and blow the tank HARD with you mouth when the problem is there ... you can broduce around half a bar that way, and that would raise the boiling point quiete a bit .... Just dont do it while racing :). Or try connecting a bycicle pump to the ventline and give it a bit .... Seriously !

Has anyone monitored fuel pump pressure while riding, and seen that this problem really is lack of pressure ?

Are you sure there is not a built in filter/strainer/mesh in the pump itself ? A blocked filter on suct. side could create boiling/vapor in pump.

I do not own one of these bikes, otherwise i would check my self.... Just guessing here ok ?

Good luck in your hunt !

Anders, DK
 
MrSmooth said:
While I ride in Florida and it get's hot, it doesn't ever get over 100F and lately it's been in the low 80's and low humidity. I would think Austrialia is a more harse climiate yet no one there has had this issue? We have crap for gas here but I do have a source for "recreational' NON-ETHANOL gas. Ethanol's boiling point is much lower than gas. I'm going to empty my tank tonight and fill it with the non-ethanol gas and ride Thursday. I'll post the results.

Has anyone had this issue with Ethanol free gas?
Click to expand...

On another forum, a person did the Australian Safari using a stock Berg in gruelling conditions and didnt report any issues at all. Maybe it is a fuel issue. I use 98 RON petrol here in Australia.

I put Ethenol (E-10) gas by mistake in my car (Ford 1997 Wagon)and it destroyed my fuel pump within 30 minutes and had to get towed to a garage to have a new one fitted - perhaps it is the fuel...

By the way - others removing the cap ball may be a bad idea, as fuel under pressure has a higher boiling point - I am putting mine back in.

Fizz
 

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