won't idle down

Squeaky back brake? Hard to control at 30mph/40kph?
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MotoMike723
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won't idle down

Post by MotoMike723 » Fri Sep 11, 2015 2:03 am

The past couple days while riding I've noticed once in a while the rpm's hold between 3-4000 after I pull the clutch in. It will stay that way until I hit the kill switch and reset the computer then it idles fine. Yesterday I noticed it was kinda rough and choppy between 2-3000 rpm as I switched into 3rd gear then cleared up above 4000 rpm. No F1 light. I haven't had a chance to plug it into the computer yet to check for codes. I had a tps code 1 time when I plugged it in but it wasn't there the last time I checked. Any ideas what to look for?
2012 SMT White
My mods
Akapovic exhaust - baffles removed
SAS block off plates
2nd flies removed
Rottweiler air box
Throttle tamer
Michelin PR3 front and rear
Short/standard stacks
Running Kev's #20 map.

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kevxtx
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Re: won't idle down

Post by kevxtx » Fri Sep 11, 2015 10:09 am

Balance the throttle bodies, what is the vacuum readings on both throttle bodies with Tune ECU?

MotoMike723
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Re: won't idle down

Post by MotoMike723 » Sat Sep 12, 2015 12:45 am

I'll try and mess with it on Sunday afternoon and post the readings. Thanks Kev
2012 SMT White
My mods
Akapovic exhaust - baffles removed
SAS block off plates
2nd flies removed
Rottweiler air box
Throttle tamer
Michelin PR3 front and rear
Short/standard stacks
Running Kev's #20 map.

MotoMike723
500cc
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Posts: 91
Joined: Sat Dec 29, 2012 2:34 am
Country: USA
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Year: 2012
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Re: won't idle down

Post by MotoMike723 » Thu Sep 17, 2015 1:26 am

Instasize_0916202240.jpg
Instasize_0916202316.jpg
1st pic is about 3000 rpm
2nd pic is idle

How does one balance them
2012 SMT White
My mods
Akapovic exhaust - baffles removed
SAS block off plates
2nd flies removed
Rottweiler air box
Throttle tamer
Michelin PR3 front and rear
Short/standard stacks
Running Kev's #20 map.

vilas69
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Re: won't idle down

Post by vilas69 » Fri Sep 18, 2015 3:44 am

Yeah, the throttle bodies are way off... it's always good to find a "tuning" problem, 'cause now the bike will be better than before :D

In this video, you will see at the bottom, at minute 00:38, on the left side of the rear throttle body, a yellow painted screw/spring that moves when you open the throttle -> that's the one you are looking for! Warm up the engine to normal temp (4/5 bars), let it idle, and check the values while adjusting the screw until they are nearly the same ;) https://youtu.be/UzORs4fXZOw

vilas69
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Re: won't idle down

Post by vilas69 » Sat Sep 19, 2015 1:11 pm

By the way, when I adjusted mine, I noticed that, although when idling the difference between the values was always less than 4/5 (around 380 hPa for both), if I twisted the throttle a little bit, keeping the engine at around 3000 RPM, the difference was up to 10/15 between cylinders... What do you think Kev, you had the same experience in any bike you tuned?

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kevxtx
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Re: won't idle down

Post by kevxtx » Sat Sep 19, 2015 1:17 pm

I only ever worried about the balance at idle, once the motor starts to spin up you will never feel 10 to 15 difference.

MotoMike723
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Re: won't idle down

Post by MotoMike723 » Sat Sep 19, 2015 8:59 pm

Thanks for the advice. I got it adjusted with both cylinders around 388. I'll check it out this week and see how it runs.
2012 SMT White
My mods
Akapovic exhaust - baffles removed
SAS block off plates
2nd flies removed
Rottweiler air box
Throttle tamer
Michelin PR3 front and rear
Short/standard stacks
Running Kev's #20 map.

MotoMike723
500cc
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Posts: 91
Joined: Sat Dec 29, 2012 2:34 am
Country: USA
City: Baltimore, MD
Year: 2012
Colour: White

Re: won't idle down- update problem not solved

Post by MotoMike723 » Sun Sep 27, 2015 8:07 pm

I still have a problem somewhere. If I blip the throttle the motor stumbles before it rev's up. It was cranking longer then normal on Friday before firing up. Today I went to start it and I had to crank it for a much longer time then ever before It finally started and then stalled out. It started again and stalled again. I now have a f1 light flashing so I hooked up to tune ecu and have a p0122 code throttle position switch low voltage (short to ground or open circuit) . Do I need to trace the wires and look for chafing or does it need a new tps? Thanks in advance
2012 SMT White
My mods
Akapovic exhaust - baffles removed
SAS block off plates
2nd flies removed
Rottweiler air box
Throttle tamer
Michelin PR3 front and rear
Short/standard stacks
Running Kev's #20 map.

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kevxtx
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Re: won't idle down

Post by kevxtx » Mon Sep 28, 2015 8:23 am

Check the big gray connector next to the throttle bodies for corrosion, then check the wiring.

MotoMike723
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Re: won't idle down

Post by MotoMike723 » Sun Oct 04, 2015 3:55 pm

Didn't find any corrosion but I did find the rear throttle body was loose in the boot. I started the bike the other day and was looking at the throttle body when the motor backfired up thru the rear boot at the throttle body. The clamp was tight but I was able to pop the throttle body out of the boot. Not sure how long this has been loose but it's only been running bad for the last couple weeks. I took everything apart, cleaned it and reassembled. Started the bike and it stalled after a minute or so. Restarted and it idled nice up to full temp. Reved fine until I let off and it stumbled a bit. If you grab the throttle kinda hard it hesitates a bit before if reves and there is some popping. Still backfiring up thru the throttle body and stalling out. I attached a video. You can hear the pop at the 13 second mark and a couple more times throughout the video. I have been running the #20 map since Kev released it and usually run the same brand of gas. I'm hoping it hasn't sacked enough dirt in to damage a valve. I currently have around 12,600 miles and I had the valves checked at 10,000 miles. I'm thinking the throttle body was knocked loose by the dealership mechanic.

https://youtu.be/2bHpweZFQAA
2012 SMT White
My mods
Akapovic exhaust - baffles removed
SAS block off plates
2nd flies removed
Rottweiler air box
Throttle tamer
Michelin PR3 front and rear
Short/standard stacks
Running Kev's #20 map.

inazumarob
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Re: won't idle down

Post by inazumarob » Mon Oct 05, 2015 8:50 pm

Could the airflow readings have been wrong originally because of an air leak on the Throttle Body?
It is possible that now the Throttle Body is sealing properly, you need to check the balance again as you may have set it with an air leak.

MotoMike723
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Re: won't idle down

Post by MotoMike723 » Mon Oct 05, 2015 10:09 pm

I thought that would be the case but what would cause it to backfire up thru the throttle body? Seems to me that a valve isn't closing tight.
2012 SMT White
My mods
Akapovic exhaust - baffles removed
SAS block off plates
2nd flies removed
Rottweiler air box
Throttle tamer
Michelin PR3 front and rear
Short/standard stacks
Running Kev's #20 map.

inazumarob
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Joined: Tue Mar 03, 2015 11:17 pm
Country: uk
City: Plymouth
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Model: SMT

Re: won't idle down

Post by inazumarob » Tue Oct 06, 2015 4:38 pm

It could be a tight inlet valve clearance (causes the inlet valve to open early while compression still in cylinder)This would let compression pressure into inlet of throttle body. This can pop off throttle body.
V twins are known for having this happen, I used to always check throttle bodies/ carburettors on any V twin for a service, especially if running rough. Some times people would not do clips up enough, so body was loose. Spray WD40 or similar around mounting rubbers when running. If idle changes (speeds up) it is drawing in fluid and burning it. Check TPS Sensor readings as they take voltage settings from angle of throttle butterflies they should be same at idle when warm, preferably around 0.65 volts according KEVTX.
Could it be fuel starvation from dirty tank fuel filters? Plenty of people seem to be having running issues at similar mileages to yours and it is traced to the filters in tank.
1 hour to change if you use Georges filter kit from Forum.

MotoMike723
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Re: won't idle down

Post by MotoMike723 » Tue Oct 06, 2015 7:48 pm

Cool. Thanks. I will try and check things out tomorrow. In the meantime I'll order a filter kit and change that when it comes in.
2012 SMT White
My mods
Akapovic exhaust - baffles removed
SAS block off plates
2nd flies removed
Rottweiler air box
Throttle tamer
Michelin PR3 front and rear
Short/standard stacks
Running Kev's #20 map.

abuhawa
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Re: won't idle down

Post by abuhawa » Tue Dec 01, 2015 10:34 pm

My previous experience related to this point to the TPS (either side of the cylinder) was faulty. Initially myself and the mechanic too suspected the unbalance vacuum between the cylinders. The TPS failure was caused by excessive heat caused further by efficient cooling. I replaced the water pump and TPS, then the problem was solved.

MotoMike723
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Posts: 91
Joined: Sat Dec 29, 2012 2:34 am
Country: USA
City: Baltimore, MD
Year: 2012
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Re: won't idle down

Post by MotoMike723 » Sat Jan 02, 2016 12:36 am

Been busy lately and haven't had a chance to update.

Got new fuel filter kit in and changed the filters out. That didn't help my problem so I dropped my bike at the dealership for service. They did a diagnosis and told me The valves were tight and needed adjusting and the tps was bad . They then started questioning all the mods that I had done and the mapping. They even asked if I wanted to put everything back on it back to stock so the could be sure that the bike was repaired properly. I told them to adjust the valves and replace the tps . A week or so goes by and they call to tell me I'm all done. Good to go. I show up to pick my bike up and the mechanic had just got back from a test ride and said it was running good once warm but was a little lean at idle so he added some fuel to it and it seamed better. I made the mistake of not even starting the bike because it was still warm and just loaded it in the truck. When I got home and unloaded the bike I started it up and with in 30 seconds it stalled out. Restarted and stalled 2 more times then called the dealership. Told them it still isn't right and they need to come pick it up as I was going out of town and didn't have time to take it back myself. They insisted it was in the mapping so I gave them permission to remap it to see if that solved the problem. Didn't help. They ended up having to contact KTM and work with a tech to troubleshoot why it was still stalling out. It ended up being a bad fuel pump. When I went to pick the bike up I test rode it before loading it this time and other then the mapping everything seemed good to go. When I got home a quick remap and 15 min reset and it's been running good ever since.

Thanks for the help trying to figure this out.
2012 SMT White
My mods
Akapovic exhaust - baffles removed
SAS block off plates
2nd flies removed
Rottweiler air box
Throttle tamer
Michelin PR3 front and rear
Short/standard stacks
Running Kev's #20 map.

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