Jump to content

17 350 sxf TPS adjustment

Recommended Posts

Hey guys. I got my TPS tool and adjusted my TPS from .50v (factory setting) to .58v. It's now harder to start and it takes a second for the idle to come down after cracking the throttle and I'll get a hesitation off idle. Do I need to go leaner or richer? (Higher or lower)? Thanks guys 

Share this post


Link to post
Share on other sites

It would flame out pretty often and I was getting lean pop. Bike is all stock btw with the exception of running VP T4

Share this post


Link to post
Share on other sites
1 hour ago, Monk said:

Go to 56 then. And dump the VP, unless you're pro or the motor is modded... 

I couldn't disagree more.  T4 (which I use in my Moto bike) is designed to be a higher octane for stock engines, and runs amazing.  Whether he is a 'pro' has nothing to do with anything.  I run it for a nice throttle response, and my bike runs cooler.  U4 (If thats what you are thinking) is leaded and requires a map change in a stock engine.

 

I would go back to a 54-56 range.  

---------------------------------------------------------------------------------------------------------------------------------------------------

 VP T4 Racing Fuel (100 Octane)

T4 is designed for stock and slightly modified 4-stroke bikes, quads, UTVs, SXSs, and other off-road vehicles used in competition

Unleaded and ethanol free, T4 is a direct pour in replacement for premium pump gas

Offers a 100 octane rating (R+M/2) that provides a greater protection against detonation

2-3% more power and better throttle response across the entire RPM range

Edited by motoxjeff

Share this post


Link to post
Share on other sites
1 hour ago, motoxjeff said:

I couldn't disagree more.  T4 (which I use in my Moto bike) is designed to be a higher octane for stock engines, and runs amazing.  Whether he is a 'pro' has nothing to do with anything.  I run it for a nice throttle response, and my bike runs cooler.  U4 (If thats what you are thinking) is leaded and requires a map change in a stock engine.

 

I would go back to a 54-56 range.  

---------------------------------------------------------------------------------------------------------------------------------------------------

 VP T4 Racing Fuel (100 Octane)

T4 is designed for stock and slightly modified 4-stroke bikes, quads, UTVs, SXSs, and other off-road vehicles used in competition

Unleaded and ethanol free, T4 is a direct pour in replacement for premium pump gas

Offers a 100 octane rating (R+M/2) that provides a greater protection against detonation

2-3% more power and better throttle response across the entire RPM range

So does a fresh tire?? 

Share this post


Link to post
Share on other sites
Just now, Monk said:

So does a fresh tire?? 

You are really adding to this conversation.  Not sure if you are normally like this....or.....

  • Like 1

Share this post


Link to post
Share on other sites

So I adjusted the TPS to .53 and it fires right up and seems to run good good but when I close the throttle, the idle drops down a good bit for a few seconds then picks back up. After a couple minutes of riding, the FI light was blinking but I didn't notice how many times and I haven't seen it do it again. Now I'm not sure which way to go, up or down? I don't think running T4 had anything to do with it as I've run it in my last 4 bikes with no problems

Share this post


Link to post
Share on other sites
On 6/11/2017 at 7:28 AM, Mxer391 said:

So I adjusted the TPS to .53 and it fires right up and seems to run good good but when I close the throttle, the idle drops down a good bit for a few seconds then picks back up. After a couple minutes of riding, the FI light was blinking but I didn't notice how many times and I haven't seen it do it again. Now I'm not sure which way to go, up or down? I don't think running T4 had anything to do with it as I've run it in my last 4 bikes with no problems

i have a ’17 FC 450, but may have some insight. I adjusted my TPS to .58-59 just like I had done on my ’16. Bike ran fine, flame outs were rare. However, I did notice I would get a constant FI light blink. I would just blink, no pattern to it. 

I took it to the dealer. It was throwing TPS codes. Mechanic said the ‘17s have different TPS values set from the factory than the ‘16s did. He reset mine to factory with the digital wrench and my bike has been fine since. I honestly do not notice any difference between the TPS value I set or the new corrected one. May be something to look into

I have a stock bike except for an FMF silencer. I also run VP T4. 

Edited by kylant

Share this post


Link to post
Share on other sites

Thanks for your insight kylant. I rode it all day yesterday with the TPS at .53 and it was still lean popping occasionally and I had it flame out a couple times. I didn't see the FI light blink anymore. Its still doing that weird idling thing but seems to run fine. I'm going to try bumping it up to .55 before I go back to stock 

Share this post


Link to post
Share on other sites

Kylant, do you know what the factory spec is for the TPS on your '17 that the dealer set it too ? The '16 spec was .40V at "zero idle" throttle plate backed off till completely closed.

Share this post


Link to post
Share on other sites

Worth noting for 2017 bikes:  The idle adjustment will actually change the TPS now, so if you are comparing notes, make sure to include the RPM your idle is set at.  Raising it on the 2017 bikes will increase the TPS voltage as well.   From what I have been reading, most suggest setting a base idle first to your liking, and then adjusting the TPS from there.  Up or down in small increments to see which way improves things, and then leave it where you like it best.

  • Like 2

Share this post


Link to post
Share on other sites
21 hours ago, FICEL said:

Kylant, do you know what the factory spec is for the TPS on your '17 that the dealer set it too ? The '16 spec was .40V at "zero idle" throttle plate backed off till completely closed.

I don’t. He didn’t tell me

Share this post


Link to post
Share on other sites
On 6/13/2017 at 0:11 PM, pentaxis said:

Worth noting for 2017 bikes:  The idle adjustment will actually change the TPS now, so if you are comparing notes, make sure to include the RPM your idle is set at.  Raising it on the 2017 bikes will increase the TPS voltage as well.   From what I have been reading, most suggest setting a base idle first to your liking, and then adjusting the TPS from there.  Up or down in small increments to see which way improves things, and then leave it where you like it best.

On the SX/XC bikes, the idle adjustment has always changed the TP setting, not new to the '17 model. That is why KTM sets TP at "zero idle", idle knob backed out till throttle plate is completely closed. '13-'15 spec was .601V and '16 is .40V and then set idle to 2250-2350 RPM. On my '16 with the TP at .40V "zero idle" and then raising the idle to factory spec 2250 RPM, this gave me a reading of .56V at the TP. Seemed lean off the bottom, so I raised mine to .58V and seems to run and start very well at that spec. You can't raise TP voltage too much on the '16 and newer bikes because the sensor down near the shifter changes the mapping in every gear and cause the FI light to start blinking and the bike will not run right.

  • Like 1

Share this post


Link to post
Share on other sites
Worth noting for 2017 bikes:  The idle adjustment will actually change the TPS now, so if you are comparing notes, make sure to include the RPM your idle is set at.  Raising it on the 2017 bikes will increase the TPS voltage as well.   From what I have been reading, most suggest setting a base idle first to your liking, and then adjusting the TPS from there.  Up or down in small increments to see which way improves things, and then leave it where you like it best.

This isn't unique to a '17. Put a voltmeter on your TPS and twist the throttle, you will see the voltage go up, same with idle adjustment. I agree get the idle adjusted properly.
To the OP, from what you're saying it doesn't add up. How about the "yellow knob"? The cold start knob. Is it adjusted properly? Around 32-34 clicks out from all the way in is a good starting point. In for cold start, pull out to ride. If everything is adjusted properly including throttle cables the knob should pop out from in by twisting throttle and letting go. Can test with bike not running.
How about the tiny in line fuel filter? Check all electrical connections. Just throwing some ideas. Don't understand why it would be lean popping and hard to start. I have a '16, went from .53 to .585, everything's is better including starting. A buddy with a '17 is even richer, .61. BTW I could tell the bike was getting "softer" off idle, initial roll on when the setting got too rich.
Keep us updated!

Share this post


Link to post
Share on other sites
3 minutes ago, rcmxracing said:


This isn't unique to a '17. Put a voltmeter on your TPS and twist the throttle, you will see the voltage go up, same with idle adjustment. I agree get the idle adjusted properly.
To the OP, from what you're saying it doesn't add up. How about the "yellow knob"? The cold start knob. Is it adjusted properly? Around 32-34 clicks out from all the way in is a good starting point. In for cold start, pull out to ride. If everything is adjusted properly including throttle cables the knob should pop out from in by twisting throttle and letting go. Can test with bike not running.
How about the tiny in line fuel filter? Check all electrical connections. Just throwing some ideas. Don't understand why it would be lean popping and hard to start. I have a '16, went from .53 to .585, everything's is better including starting. A buddy with a '17 is even richer, .61. BTW I could tell the bike was getting "softer" off idle, initial roll on when the setting got too rich.
Keep us updated!

Maybe the yellow knob is pulled out? 

Share this post


Link to post
Share on other sites

I have never adjusted the yellow "cold start" knob. I did not measure at idle. I measured by bumping the starter. I talked to two reliable shops who reccommended setting it back to the original position and having it remapped. With everything I've read, .58v was way too rich which made it hard to start, had the big bog off idle and threw a code. Oh, and made the idle stay high for a few seconds. Now, at .53v it seems to have the same problems as stock (.49v), but it does that idle drop thing. I'm just going to set it back to between .50v-.52v which is what I was told was stock, and have it remapped

Share this post


Link to post
Share on other sites
2 hours ago, rcmxracing said:


This isn't unique to a '17. Put a voltmeter on your TPS and twist the throttle, you will see the voltage go up, same with idle adjustment. I agree get the idle adjusted properly.
To the OP, from what you're saying it doesn't add up. How about the "yellow knob"? The cold start knob. Is it adjusted properly? Around 32-34 clicks out from all the way in is a good starting point. In for cold start, pull out to ride. If everything is adjusted properly including throttle cables the knob should pop out from in by twisting throttle and letting go. Can test with bike not running.
How about the tiny in line fuel filter? Check all electrical connections. Just throwing some ideas. Don't understand why it would be lean popping and hard to start. I have a '16, went from .53 to .585, everything's is better including starting. A buddy with a '17 is even richer, .61. BTW I could tell the bike was getting "softer" off idle, initial roll on when the setting got too rich.
Keep us updated!

Makes sense twisting the throttle changes TPS considering it is a throttle position sensor.  I was led to believe the earlier bikes had a separate idle circuit however.  Either way, good to get idle dialed in first.  =)

Share this post


Link to post
Share on other sites
I have never adjusted the yellow "cold start" knob. I did not measure at idle. I measured by bumping the starter. I talked to two reliable shops who reccommended setting it back to the original position and having it remapped. With everything I've read, .58v was way too rich which made it hard to start, had the big bog off idle and threw a code. Oh, and made the idle stay high for a few seconds. Now, at .53v it seems to have the same problems as stock (.49v), but it does that idle drop thing. I'm just going to set it back to between .50v-.52v which is what I was told was stock, and have it remapped
@FICEL comments above clearly explains the correct way to adjust.
Have you double checked the TPS connections? Reason I say this is because I had this happen, bike will start like crap and bog.

Share this post


Link to post
Share on other sites

How are you guys setting the idle rpms? I wish this things had a tach on the hour meter, that would make this easier. 

  • Like 1

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Reply with:


×