chop throttle and cold bike cuts out

hi all, troubleshooting a problem i've had for a while on my 2011 570FE.

if the bike is cold and i chop the throttle while the bike isn't engaged (neutral or clutch in) it's almost like i can hear the intake burp a little and the bike cuts out. it's not always the easiest thing to reproduce, but can hellen even when i'm downshifting and quickly blip the throttle to match revs.

i recently replaced my fuel pump with the CA Cycle works and while i was in there checked the TPS. it was a little below the .601V that the manual and forums reccomend so i adjusted it. now that i'm back on it and riding, problem is still there...maybe even a bit more pronounced.

could it be TPS adjustment? other ideas?

thank you

over oiled filter. go for a ride on the road without it and see what happens?
Injector starting to block?

Taffy

What idle RPM is it set at? 2009-2011 manuals specify it as 1700-1800 RPM, 2012 manual as 1800-1900RPM - and it's the same motor so I take it as an updated recommendation for all years.

Unlikely but imo possible: How's your battery? I had a marginal battery in mine (original battery 4 years later). It did start the bike, but I had a fairly strong hunch that it ran better around idle when I did drop a good battery in. Note that I'm not yet technically convinced that it's either possible or impossible that this has an effect

Hi whapworth,

I'm not too familiar with the later models but if it were me, I'd be having a look at the throttle body to see if it is 'sooted up' so to speak. It's amazing how engines respond to a clean t/body. Is it only when cold? You can easily clean with a can of carby clean....best to remove the t/b.

Also, have a look at the plug, are they iridium? I don't know but if it's worn, obviously regap/replace.

Reset/ check tps to factory setting then you can eliminate that.

Just some other stuff for you to consider.

Good luck,

Damo

Also, I'll take inspiration from Jon Andersson and ask if you've tossed the inline fuel filter in the injector assembly as far into the bushes as you can muster?

Wow, awesome responses all, thank you, will try to go through them all.

Sorry for the long response, just wanted to be thorough and respect the time you all put in already...thanks again

1. will try to ride with filter out and see if the filter is over oiled...great thought
2. hope it's not the injector blocking, but maybe...put some injector cleaner into the fuel the other day to see if i could fix the problem...
3. idle is currently set between 1700-1800 as specified in the manual, but i does feel low, even there, as the motor bogs the slightest bit on launch...is that true that 2012+ specify 1800 - 1900? can someone confirm? if so, that could be all the difference, at that pace, the motor sounds like it's doing a lot of work at idle..? nonetheless will try
4. battery is literally BRAND new ballistic, was just replace with an older one...problem same with both honestly
5. throttle body is clean as a whistle, just had my motor out to put a timesert in for a stripped oil drain plug and cleaned EVERYTHING while i was at it. throttle body was already pretty pristine, now ever more so, and problem the same
6. plug also brand new NGH LKAR 8AI - 9, problem the same
7. TPS i just did when i had the motor off. it was low relative to factory spec...initially measure around .590, got it back to factory .601, still same, may actually be worse now that i think about it...but everything i read said if anything better to have a higher tps reading...??
8. new fuel filter just replaced in the tank (MAHLE OEM), but no, no filter for the injector assembly...guess i should do that, but there is literally no space in that area...well i'm sure there is actually because have seen other posts..but nonetheless it's tight.

conclusions...will try each of the following independently:
1. possible air filter is over oil..will try out with unoiled filter first
2. maybe i should clean the injector...never done it but assume pretty straightforward...??
3. will bump idle to 1800+
4. TPS is dead on, would it be better lower, where it was? which goes against all that i've read elsewhere
5. at some point will throw another fuel filter in there...but right now given new pump and lines and intake filter would think it's pretty clean. Also does the extra filter put undo stress on the pump?

I can confirm that the 2012 manual states 1800-1900 - see links in my forum signature if you want to double-check I checked the 2009, 2011, and 2012 owner's manuals.

1900 RPM did seem high to me! That said, when I just got my bike I dropped by the local KTM/Husaberg/Husqvarna dealership for a chat. They've been in the business for quite some time. The owner was super nice, immediately spotted from a few meters away that my gear lever had almost unbolted itself, and then he fixed it ... next he casually stepped over and raised the idle a bit - to what RPM I don't know but noticeably higher than I had set it believing it to be correct - and said "there, they usually are better like that".

Re. the fuel filters: You want to COMPLETELY REMOVE the small black or grey filter in the injector. I'm not 100% sure what the best practice on filtering is - maybe an inline filter on the hose? Maybe something in the tank? I'll advise you to search the posts here for better info than I could give by guessing

Oh and btw, as far as I know, the Ballistic battery you have is a LiFePO4? FWIW I can confirm that the battery that behaved better than the tired SLA was also a LiFePO4.

@tourist this is awesome, thank you.

will definitely bump the idle first and test, as that's the easiest to troubleshoot.

will look into cleaning the actual injector...wish i'd done when i last had the tank off

Fuel filter IN TANK is BRAND new, fuel filter near disconnector is non-existent...hesitant to add one, but guess i should...he has a pretty good write up here: https://gardinerfamilyadventures.wordpress.com/2012/04/14/fuel-injection-how-to-keep-it-working/

good news on the ballistic...solid batteries

Checking in, started some trouble shooting

1. replaced the oiled filter with a spare un-oiled filter i had. no difference, then removed filter quickly and drove around, still nothing. so not a question of an over-oiled filter

2. bumped the idle up to 1800-1900, up from around 1700. still no difference, other than that the bike got hotter faster

3. ordered one of these filters, Quick Disconnect Fuel Filter - ZipTy Racing Products , and at some point am going to clean out the injector...following some instructions i saw on youtube on how to activate the injector with a 9V battery.

4. don't think it's the tps, and not going to mess...will just retest it when i pull the tank off to clean injector.

5. clean throttle body again, but pretty clean

wish i could post a video as i was easily able to replicate the problem on video at idle, even with the bike hot too, just chop the throttle a bunch and eventually cuts out and can hear a big decompression from the intake.

will post back when i finally get the injector cleaned and back together.

maybe this video link will work

https://photos.google.com/share/AF1...?key=WXBtSGJ5Z3A4QUxPcEpoWDNKcVFBTE00ME1TYUF3

I also am having this issue on my 2005 yours is fuel injected though right ? Mine will die when trying to rev match and or chop the throttle like yours. I changed my sparky it improved but still no cigar so I'm guessing this is fuel supply related I'm running a tad rich aswell I think so look at that also, Gotta bite the bullet and strip my carb but the damn thing looks like a pain in the Arse to pull out

salty, sorry to hear dcfc550...

i haven't cleaned my injector yet as i'm waiting for a fuel filter i purchased from ZipTyRacing.com to arrive. then i'll pull it apart and report back.

as far as a carb clean...sure it's not too bad and always a good thing to do. go for it

So, i pulled my throttle body, back cleaned my injector with throttle body cleaner and compressed air, replaced the quick disconnect on the fuel line with the zipty all in one 2x fuel filter, cleaned the entire throttle body spotless, and all other parts as well.

i used a 9v battery to open injector, but with limited success...couldn't seem to get it to open consistently while i was applying air from the compressor...so wondering if i should have done this better and how.

since ridden about 20mi...it's better, definitely doesn't cut out as frequently as before, but still if i chop the throttle really hard (especially when the bike is colder) i can still get it to die. for now, gonna just keep riding it, but may try to reclean again and figure out a more reliable way to hold the injector open while i blow air through it.

if any one has more thoughts on why it might be cutting out...all ears

cheers

Check the spray pattern of your injector on some cardboard. Should be a nice round pattern. That should tell you if it needs to cleaned.