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2013 KTM 250 SX-F Consistently Pops on Decel

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Does anyone have a new 2013 250 SX-F and notice much popping on deceleration? My son is at the track right now, called me and said it's popping on decel almost like on his old carbed bikes when they were jetted too lean on the pilot. It's 73 degreesicon1.png there at the altitude is 3,650. The bike just turned over 2 hours and we have not done anything to it yet but change the oil and clean the air filter. Anyone replace the stock map switch yet with the more aggressive one?

Thanks!

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The first thing I would try is resetting the parameters on the EFI system. Your bike uses a closed loop system and it can "re-learn" the operating conditions that it is in if you do the following:

Start the bike with no throttle input and let it run for 5 minutes - don't touch the throttle!

Shut off the bike for 30 seconds.

Re-start the bike and you are ready to go.

Hopefully this simple "fix" will help you.

If is does not then I would start to look for exhaust leaks.

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Does anyone have a new 2013 250 SX-F and notice much popping on deceleration? My son is at the track right now, called me and said it's popping on decel almost like on his old carbed bikes when they were jetted too lean on the pilot. It's 73 degreesicon1.png there at the altitude is 3,650. The bike just turned over 2 hours and we have not done anything to it yet but change the oil and clean the air filter. Anyone replace the stock map switch yet with the more aggressive one?

Thanks!

My suggestion would be to look into the BAZZAZ self mapping unit/ Fuel controllers, A) it accounts for any combination of performance modifications B) Incororates date from countless conditions such as altitude, fuel type, tempature, humidity, as well as performance mods.

Feel free to give me a call if you have any questons 909-597-8300 x107

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The first thing I would try is resetting the parameters on the EFI system. Your bike uses a closed loop system and it can "re-learn" the operating conditions that it is in if you do the following:

Start the bike with no throttle input and let it run for 5 minutes - don't touch the throttle!

Shut off the bike for 30 seconds.

Re-start the bike and you are ready to go.

Hopefully this simple "fix" will help you.

If is does not then I would start to look for exhaust leaks.

Sorry, not a 'closed loop' system.

Keihin FI only monitors air pressure and temperature.

It has no post-combustion sensors.

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Krannie, Thanks for the clarification, i did hear this from another friend as well so there is no sense in wasting time with something that positively won't work. I am going to try some different fuel just to rule out the possibility that the first fuel I put in the bike from new was not fresh enough. I have a sneaky hunch that most of the stations where I live have premium that has been sitting around for quite a while. I was thinking of purchasing some VP Street Blaze unleaded 100 octane as that worked great in the RMZ's we used to race 3 years ago. Pump gas is very inconsistent now days.

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Sorry, not a 'closed loop' system.

Keihin FI only monitors air pressure and temperature.

It has no post-combustion sensors.

Only the first gen 'bergs with the 70º engine came with closed loop. They switched to open loop in 2010....

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The 'start and wait' comment about the ECU is valid however.

The MAP sensor and the temp sensor will 'listen' if you let the bike sit and idle for 3 minutes.

Your symptom is one of leaness in most cases, and might be as simple as a loose throttle body boot, or and under oiled aircleaner.

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I spoke with the KTM dealer rep for So Cal and he wants me to take the bike back to my dealer where originally purchased from and have them connect up to the XC-1 diagnostic tool to check and see if the TPS is set within the measurement of .596 to .601. If it is out of this range they will set it accordingly, then if there is anything else that they see on the fuel mapping, adjust to where that should be. I am taking it in on Friday and see what the heck is going on. My son was at Pala this morning and parked right next to him was another new '13 KTM 250 SX-F so he asked the owner if he noticed that popping on decel and his bike does it too, only my son's bike is worse with popping as well as running crappy getting on the gas out of corners. Our 2011 EFI bike ran better than this 2013 bike so we are not too pumped at the moment.

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