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TPS Reading too High?

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I am experiencing some stalls and hard starts. Seems to happen after riding for 10-15 minutes. It will flame out and be hard to restart for a minute or two..

I figured I may have to adjust the TPS setting.

I got the tpstool. I attached the tool and connected my meter. 
My meter is showing .757 (Can someone verify from my pic if I have the meter set properly?)

Bike Info: 2016 350 EXC-F 420 Miles. I purchased it used. It does have an FMF exhaust on it and it appears to be desmogged.

From the videos I've seen I feel like the motor would be racing set this high (.757). 

Is this reading correct? Would I be experiencing some issue with it set to .757? 

I'm not all that sure if I even have my meter set properly... so any info is appreciated.

I have xposted this to KTM talk as well. Id like to figure this out before Sundays event.

 

Thanks for any help!!

TPS Reading.jpg

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Are you sure the idle is high enough, they need a quicker than normal idle around 2000rpm+, otherwise on the 350 , try .69 tps ,  if you are not dealing with a low idle.

meter is okay

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Ditto what was said above.  .757 is higher than where most end up, but idle too low will definitely contribute to flameouts.  If the idle is good, then go down a bit on the TPS and try again. 

Would you please post a link to the thread on KTM Talk so I can reply there as well?  
 

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14 hours ago, sirthumpalot said:

Ditto what was said above.  .757 is higher than where most end up, but idle too low will definitely contribute to flameouts.  If the idle is good, then go down a bit on the TPS and try again. 

Would you please post a link to the thread on KTM Talk so I can reply there as well?  
 

Thank you both for your help!

 

Here is a link to the post on ktmtalk

 

http://ktmtalk.com/showthread.php?534626-TPS-Reading-to-High&p=5115803&posted=1#post5115803

 

 

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So Went down to .64 with the tpstool. 

I fired the bike up and it seemed to be idling at lower rpms. Really low. Low enough that I figured when I touched the throttle it would die. And that's what it did.

I pushed the TPS up to .74 and the bike fires up and seems to be idling at a good clip and does not die when I blip the throttle. 

 

One would think that it would be in good working order. But as I originally mentioned, after riding for a bit, it will stall from a stop then take a few minutes to fire back up. 

This is starting to really bother me.  

 

Thoughts?

 

 

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Try the TPS at 0.64v, and then raise the idle to the correct RPM, then test again. The bike needs to be warmed up before testing. 

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19 hours ago, sirthumpalot said:

Try the TPS at 0.64v, and then raise the idle to the correct RPM, then test again. The bike needs to be warmed up before testing. 

I put TPS at .64. and turned the idle screw CCW about 5 clicks. I made sure the bike was warmed up prior to this.

Everything seemed great. I took it for a ride and when I let off the gas it starts popping. Just...pop,pop,pop,pop,pop,pop... Then I blip the throttle and I get a bigger POP.

While on the gas it seems a OK. 

I took it home, pushed the TPS up to .668 and took it for a ride. Same popping/back firing.

Please Note: The bike just idling, after its warmed up seems to slowly "surge" up in down with its rpm's a bit. 

 

Should I continue the path of pushing the TPS up, or maybe turning down idle a bit?  What is the popping from? To much air, not enough fuel?

 

Again, thanks for all your guys help on this! Id be lost otherwise.. 

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I would solve the surging idle issue first, then worry about the popping after the idle is stable.    Assuming the idle is at the proper RPM; it almost sounds like you've got an air leak on the intake side somewhere.  Double check the clamps on the throttle body.  Also when was the last time the valves were checked?  Even if .64 isn't perfect for your bike, you shoudln't be seeing unstable idle with the TPS in that range, which makes me think that something else might be causing the idle issue.  That something else might also happen to be the source of the popping as well, but tackle it from the angle that you're trying to solve the unstable idle first. 

 

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Throttle body clmaps and boots look solid.  I just turned the Idle down 5 clicks (CW). I don't get the surge anymore on the RPM at idle. 

I then decided to set the TPS back to .64. It fired up nice. I have not had a chance to ride it (damn day job) but wanted to post up where I'm at. 

I took a quick video of the bike idling.. Any chance you can take a look at the link and let me know your thoughts as far as my idle sounds??

 

Link to MP4 of Bike at Idle

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your in the ball park

 

on a side note surging is normally having a lean spot , in that particular idle setting. At  .64 , id say you'll need a fuel tuner to really fix the details in the mapping with your configuration, but you could do the offroad map as a base. However,  The fuel tuner presets are normally close and  made for stock map. So if you did get the alternate map, in addition to a fuel tuner, you'd have to develop better settings than the presets, more than likely.

 

the stock map is missing the accelerator pump feature, and that setting is crucial to getting the most out of the motor. That feature can be obtained with alternate map or fuel tuner, but it needs settings of perfection for the most gain.

Edited by Spud786

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3 hours ago, Gath3r said:

Throttle body clmaps and boots look solid.  I just turned the Idle down 5 clicks (CW). I don't get the surge anymore on the RPM at idle. 

I then decided to set the TPS back to .64. It fired up nice. I have not had a chance to ride it (damn day job) but wanted to post up where I'm at. 

I took a quick video of the bike idling.. Any chance you can take a look at the link and let me know your thoughts as far as my idle sounds??

 

Link to MP4 of Bike at Idle

I just went for a quick ride. I warmed the bike up. It seems to idle good where I'm at with the Idle screw.

So withe the Idle knob turned CW 5 clicks, putting it back to square one, and TPS set to .64 it sounded a whole lot better. Still a little popping on deceleration  but a lot better than it was before. 

Should I continue to screw with the Idle knob and TPS? Would the idle a tad high cause the deceleration popping/back firing?

I plan to take it for a longer ride tomorrow at lunch to see how it goes in different terrain and speeds. I have a ride scheduled for Sunday and would like to have it running as good as possible for it. After that I may just send the ECU out for a Mapping. Thoughts?

Thanks again for all your help!

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If it's better then take it for a ride and see how it runs on the ride.  A little popping won't harm anything.  If you have an exhaust that is more open than the OEM then a new map could help.  You would likely need to turn your TPS back down to the .6 range after installing  richer map.  

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I remember when i had my 13 350SX-F and stock it was like 54.4 or something really low, i also had back fire, i raised it to 63.6 and it worked great, but after a little while i had idle issues where if i would blip the throttle it would stumble and almost sound like it would stall. I raised it to 73 witch is crazy high and although it fixed the idle issue it had a low end bog so i turned it down, ended up getting fed up with it, it also started having hard start problems though the bike had 100 hours, ended up selling it not long after. 

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