Adjusting TPS Voltage

This video describes how to check the volatge coming out of your TPI's throttle body positioning sensor and how to adjust it using your TSP idle screw for an optimum idle setting.

[@johnellersick5172]

Spot on video bud you just saved me a ton of money I was so fed up with this 19 300xcw I was ready to trade it in Mine was at 670mv after idle screw mod hanging idle nd pipe bang at this time I set to 590 as you recommend and have air screw 2.5 turns out Everything is spot on now I owe ya lunch 👍 Ty sir

[@52yamahar1]

Great bit of info, exactly what I was after 👍🏻

[@sberga5058]

Great video and info! Thanks

[@andreserta]

Thanks a lot for this useful info. I was looking at TPS Tool to do the adjustment of the throttle and with this hack save good money on my KTM EXC 500F SIX DAYS 2020. Thanks and good job 👏

[@brianjones7681]

Just checked my 22 EX300. It has the Slavens screw in it. It was at 0.628. I adjusted it to .595.

[@human1513]

Often you will require to adjust the idle screw, which is a throttle plate bypass via a hole in the throttle body to allow more air into the motor at start up and idle only. The reason for this idle screw as KTM calls it is so the bikes will run lean to pass the emissions requirements. It truly is an air bypass screw not an idle speed screw as it progessively (as the screw is turned) opens and closes the bypass passage to control the air allowed into the motor via bypassing the standard intake via the throttle butterfly, plate. Each year 2019, 2020, 2021 & 2022 all seem to have the KTM "idle screw" set at a diiferent # of turns out. Meaning each year has a different set turns out This KTM "idle screw" is the slotted silver screw on the left side, beside the cold start knob.

[@chrisbracken7889]

Great help thanks

[@chrisbracken7889]

Great Pro Tip !

[@human1513]

Note: the KTM labelled "idle screw", the slotted silver screw next to the cold start knob is NOT a mixture screw. Carburetors have mixture screws because their screw affects both the air & fuel. On fuel injection the fuel and air enter the engine from different locatiions. That slotted silver screw is an air screw only. Actually it is a throttle plate air bypass screw that controls the opening in a bypass hole in the throttle assembly. Its purpose from KTM is to allow some more adjustabilty outside the software, so that at start up and idle speed only the bike will meet emissions. I spoke to a large dealer and the mechanics told me many riders are seizing theiir TPI bikes because they do not understand how fuel injection works and for example are twisting on the KTM idle screw and leaning them out too much. Or doing the throttle screw replacement but know not how to set the TPS voltage nor the idle screw. Many riders think it is just like a carbureted bike. Wrong! Good luck and be sure. Hope this is helpful.

[@lostinpa-dadenduro7555]

What would happen if you closed that off by turning all the way in and then setting the idle?

[@myronstambaugh761]

The mixture screws DO NOT affect both air and fuel. Idle screw affects slide height which is air only. The air screw affects the idle air to the pilot jet only, no fuel, no slide. On carbureted 2-strokes the only way to change fuel flow is by changing jets. Raise the slide or open the idle air screw too much and a carb bike will be too lean as well as an injected bike. I have corrected hanging idles for people by merely dropping the slide enough to allow the idle circuit to take control of the idle again.

[@sokol0903]

good time, please tell me if you unscrew the idle speed screw, the one that moves the throttle, what value will be on the multimeter?

[@blacy001]

i have the screw all the way out and im still getting .625 on a 2019 te300i

[@boblogIIIfan]

Thanks for the video. I have a 23 150exc. Is it still 600mv ? also do you sell the wakeup tool or can i just bridge the wires or something ? thanks

[@sbmotoperformance]

Yes, .580 - .600 mv is the desired range. We do not sell the wake up dongle and you can jumper the plug. If you hold the plug with the locking tab facing up, it's the bottom left two ports that need to be jumped together to wake up the bike.

[@Stealthbruva]

I’ve also set mine to 5.9mv I’m about to install the tsp kit with the high compression head for the 2021 300 6ays . Would I need to further adjust the tps with the kit im gonna install. I also have a fmf titanium powecore 2.1 on it if that makes a diff .

[@sbmotoperformance]

Nope you should be good. With the colder winter months, we have found that 600 mv seems to be a little better idle setting.

[@teamwork2682]

When my bike goes in 4 or 5th gear and then get back to 2nd gear it losses the power and then i have turn the switch off from keys and then i have to start the bike. I'm not able figure out the problem.. Any suggestions??

[@jbstrongman]

The manual says the idle on my 2021 300 tpi should be 14-1500 that seems so high

[@ericwinner3587]

Great video. Is this voltage range universal for 2020 KTM 250 and 300 TPI bikes?

[@sbmotoperformance]

Yes it is. We see some variance in bikes, and weather temps. I have actually been setting them at 600 mv lately and they seem to idle a little better in the cold.

[@cihan.kurucu]

Hi. I did my Hyosung tps 1.1v open and 4.6v open. Now it is like a rocket.

[@matthewgrew865]

Hi , could u tell me plz , must I adjust both throttle sensors to 580 mv , I have the 2011 super Moto 690 It’s won’t stay idle ?

[@sbmotoperformance]

Sorry, we only work on two stroke dirt bikes. Good luck.

[@125nsr]

Hello, I have a 4stroke Husqvarna 250 Te 2012, and my tps is 0.99v. It can be only 0.95 at minimum. Every video I look it's around 0.6v. Do you know if 1v for my model is normal ?

[@sbmotoperformance]

We only do two-strokes my friend. Sorry.

[@motofamily461]

I have a 21 Husqvarna TX300i TPI 2 stroke. What do I set the air idle screw at before I test the voltage and dial it in.

[@southbaymotoperformance9127]

3.0 to 3.5 turns out from fully seated

[@vinny2t491]

What are the odds that after adjusting my newly installed idle screw that when I went to check it that it was exactly at 590mv. Crazy. I wonder if it resets itself whenever you install the ECU? It just seems unlikely that I would have wound up at that exact measurement after fiddling with it and the air screw a number of times.

[@sbmotoperformance]

The ECU does not reset itself. Getting a 590 mv reading after installing the idle screw is just sheer coincidence. I would go buy a lottery ticket next.

[@vinny2t491]

@@sbmotoperformance haha, wow that's pretty unbelievable!! Going to buy one today. Thanks for the response Steve, I'm loving my TSP kit. Your customer service is second to none. I'll be posting some videos to my channel soon showing off my bike, I'll make sure to recommend people speak to you if they are looking to smooth out their TPI and gain a little more power. Cheers!

[@harleyosterlund5796]

Hi guys. Replaced my ccp sensor and added idle adjustment screw to my 2019 250 tpi. Followed this video and set mv to 590. Bike started up first kick with flip flops on but is throwing 5 codes??? I disconnected the battery and the ecu but the codes are still there. Here is what I have in order 1-5 long 2- 9 short 3- 1 long 3 short 4- 6 short 5- 1 long

[@steveboardman9103]

All of those codes seem to be related to the Crank Case pressure sensor, the throttle positioning sensor and the aliment pressure sensor. Are you sure you reconnected all of the electrical connections prior to starting the bike. Give us a call and we can discuss over the phone.

[@harleyosterlund5796]

@@steveboardman9103 what’s your number sir?

[@steveboardman9103]

@@harleyosterlund5796 Listed on our web site: 408-459-8794

[@jpp2422]

This is a great thread... One last question... for a 22' 300 with the voltage at .600..what are your thoughts on the air screw? 1 Turn out is where it's at currently and does not seem super responsive. thanks!!

[@sbmotoperformance]

For the 2022 300, the air screw should be 3.0 to 4.0 turns out from fully seated.

[@jpp2422]

@@sbmotoperformance Thank you!

[@redrider533]

@@sbmotoperformance 3-4 turns out (onthe air screw)with the idle screw mod? im slightly confused. the AIR SCREW (side of the throttle body) controls air bypass around the throttle plate so that the engine has air when the throttle plate is closed in order to idle. Similar to an IAC (Idle AIr Controller) on a car. This is because the throttle plate is completely shut on closed throttle correct? So when you pull the preset idle allen screw from the TB and install the Manual Idle screw your now using the Throttle plate to let air into the motor rather than the AIR Screw. So in doing this two things happen. Adjusting the new throttle screw to get the desired idle also increases the TPS voltage at idle. (no longer .580 to .600) Second why are we not screwing the AIR SCREW all the way in to shut off the bypass air? The throttle plate is now allowing air through. I base this all on my 2023 GAS GAS 300. Ive done the throttle screw MOD right from brand new. But never adjusted my TPS voltage back down which a assume i need to do now. the bike seems rich down low because the TPI voltage is high and telling the ECU to add fuel. feed back please

[@madgamehd6079]

Does the calibration of the oil pump start when I connect the Wake up plug?

[@southbaymotoperformance9127]

The oil pump does not get calibrated. If you are asking about priming the oil pump, there is a sequence for that. Hold throttle wide open, plug the dongle in, count to 10, release the throttle and oil pump should initiate the priming sequence. YOU should hear the oil pump clicking and oil will be pushed through the oil injection line and into the throttle body.

[@DMC-179]

Thank you for this video! Got a 2021 GasGas EC300 with Coober ECU and Coober Head + idle screw mod. Could you please give me an advice how many turns my air screw should be out? :)

[@sbmotoperformance]

I wasn't aware Coober made a head? We don't use those products so I don't know what to tell you about tuning your air screw. Turning it in makes it rich off idle and turning it out makes it lean off idle. Play with it in 1/2 turn increments and then 1/4 turn increments and see what you and the bike likes best.

[@DMC-179]

Thank you

[@DMC-179]

@@sbmotoperformance I see 815 mV. If I want to get below 790 mV, the idle screw is unscrewed. In parallel, I have another throttle body including sensor, which is still completely original, without idle screw mod. Completely untouched. 869 mV are displayed here. Any suggestions on this 😅

[@sbmotoperformance]

@@DMC-179 I have no clue why your voltages are so high. I have been told that the magnets inside the TB are paired with the TPS and cannot be interchanged with other sensors. I had a customer learn this the hard way. Not sure if that applies here but it's my only thought. Or your volt meter is off. At the end of the day, don't worry so much about voltage, and just set the idle to a smooth rhythmic level that doesn't stall or leave you with a hanging idle.

[@DMC-179]

@@sbmotoperformance sounds good! Thank you 🙏

[@mikeyx2415]

Recently installed a TPS guard and in the process, the TPS moved a bit. Got it reseated and screwed back into place. Bike seems to run like normal but should there be any cause for concern with it moving somewhat during the install? Thanks!

[@sbmotoperformance]

Not a fan of the TPS guards for that reason. Never seen a TPS get damaged from riding. I would check voltage and adjust. You may have to file a window in the end of the guard to access the wire pins.

[@0ooooooooa]

@@sbmotoperformance smashed TPS cover on the rock during first ride on my EXC lol

[@neumann534]

so with the TSP kit Medium Comp head and tune, how much would you say the air mixture should be turned out?

[@sbmotoperformance]

Depends on what year bike and what size motor. They are all a little different.

[@neumann534]

@@sbmotoperformance 2020 300 tpi

[@sbmotoperformance]

@@neumann534 Anywhere from 2.0 to 3.0 turns out from fully seated seems to work best. Start with 2.5 turns out from fully seated and adjust from there if needed.

[@hardendurobosnia17]

THANK YOU! Iwas a 573, now I'm at 590, my bike has a bit of hesitation (CCPS) probbably, should i go to 600?? PLEASE

[@sbmotoperformance]

If it idles fine at normal operating temps, then no need to go to 600 mv. increasing idle speed will not fix the hesitation. YOU can try the air screw, but we would recommend the TSP Power Kit if you want your bike to run perfect with increased performance.

[@hardendurobosnia17]

@@sbmotoperformance we don't have those kits in my country, it idles a bit low, so should i go to 600 mv? Does that less than a milimeter turn make the diffrence The biggest thing i've noticed is that my bike was running terribly (sounded rich) for the first 3 seconds (AFTER PUSH STARTING) the bike, now at 590 it's completely normal

[@sbmotoperformance]

@@hardendurobosnia17 580mv - 600 mv is the rage specified by KTM. Some bikes need a bit more than 600 mv. If you turn the idle screw in too far, you will get a hanging idle symptom. Yes, very small increments on the idle screw make a big difference.

[@matteopalmieri2255]

It’s possible, have a maximum value voltage of TPS in a maximum throttle position? Because I have both a used bike, and I think the TPS it was modify and I need to reset. Because I’m not really sure, but in this value 580/600 mV don’t work correctly, now run with 691 mV Thanks a lot

[@southbaymotoperformance9127]

Some 2022 and 2023 model's TPS voltage does not fall in the specified range. Some need much higher voltage and some need much lower voltage and we don't know why. Earlier years, they all fell within the specified range.

[@Michael_Douglas007]

I am the second owner of my 2020 ktm 300 XCW and the first put the idle screw mod in. I don’t trust 100% that he set the tps and idle screw mod at the right distance. Does this fix that? In someway? Like if the distance was set incorrect does it not matter as long as the voltage is at that measurement?

[@southbaymotoperformance9127]

The only thing that matters is the voltage. Check and set the correct voltage per the video instructions. Once voltage is set, the air screw should be set somewhere between 3-4 turns out from fully seated.

[@scottevans3389]

If the volts are reading over 600 what would be the symptoms? And if there are any symptoms why are we all doing the idle screw Mod?

[@sbmotoperformance]

KTM recommends the baseline setting of the TPS to be between 580-600 mv. Many bikes like a higher voltage than 600 for a rhythmic and consistent idle. Sometimes we have to ignore the baseline setting and go with what the bike likes. If the voltage gets too high, and the idle screw is turned in too far, the bike will have a hanging idle. Installing the idle screw is not a mandatory mod for the TPI bikes. However, it allows the rider to manually set or adjust the idle using the newly installed idle screw, and conversely, now able to set the air bypass screw to adjust off-idle throttle response to a rider's preference (rich or lean) which only affects from idle to about 1/4 throttle.

[@Pinkerpops]

Is this the same on the 23 2-Strokes? I think I’m having TPS issues due to the throttle cutting out at higher RPMs and the Fi indicator light is on.

[@sbmotoperformance]

In 2022 and 2023 some of the voltages were different. Some where higher and some were lower and we don't know why.

[@0ooooooooa]

did you fixed that? i have same issue

[@thomasfamilyactioncam2466]

What should the voltage be on my gas gas ec250 2023?

[@sbmotoperformance]

Unfortunately, in 2022 and 2023 many of the bikes we saw had very different voltages that fell outside the range of .580 - .600 mv. Some were lower and some were higher than the specified range. We don't know why. I can't answer your question without knowing where it was set from the factory which should be done prior to removing the OEM set screw and installing the manual idle screw.

[@rotards3036]

Hello, my bike doesn’t t start after installing an aftermarket tsp protection, i set to 0,590 v and still not starting, throwing 6x short code it’s a 2022

[@southbaymotoperformance9127]

Some of the 2022 and 2023 bike's TPS voltage was way different than the range discussed in this video. Just keep turning the idle screw clockwise in small increments, 1/8th of a turn at a time, until the bike has a nice smooth, but low idle.

[@rotards3036]

@@southbaymotoperformance9127 now i t s throwing 3long3 short code and 3 long 4 short code , never started in any change

[@jpp2422]

weird mine read .000 even after i plug in the wake up dongle. even tried pushing the pins way in, etc. any tips?

[@steveboardman9103]

The only reasons it would not be reading a voltage is your wake up dongle is not waking up the bike? Can you hear the fuel pump cycle and the dash lights come on when you plug in the wake up dongle? If yes, then the dongle is working. Then your pins are not fully inserted and not making contact. It takes a few tries to get them fully inserted and making contact. Try a few different spots around the wire.

[@jpp2422]

@@steveboardman9103 I think the dongle is not working properly. just realized it's not doing those things... i have the tank off now ..will put it back on and try again tomorrow.

[@stevenmcallister2230]

I have a ktm sxf 250cc got pigtail and multimeter it’s kick start but doesn’t run more than me 10sec can I put pigtail in and use meter to adjust bike TPS as someone tried to do it by hand and EFI light flashes 6times tell me it’s throttle body sensor to high or to low can u help me 🏴󠁧󠁢󠁳󠁣󠁴󠁿

[@southbaymotoperformance9127]

What year is your bike? 6 flashes means your TPS is out of adjustment. Most TPI bikes, not all, need to be in the range of .580 - .600 mv.

[@stevenmcallister2230]

@@southbaymotoperformance9127 hi I’ve got it set at .600same as my boys his TPS IS .642 and idle is set at .500 so his bike is 2011 mines is 2012 his bike runs like a dream mines I’ve but new fuel pump new ECU new TPS it starts fine but dies after 7 to 10seconds injectors all firing good so someone was saying they think might be valves are not opening and closing correct I’ve changed everything nearly still dies u thin k it could be valves thanks for ur reply

[@Alex-pb1pb]

​ @South Bay Moto Performance whats gonna happen if its set too high?

[@sbmotoperformance]

Typically with the TPI bikes, if you set the idle too high, you will notice a hanging idle on decel or a chopper throttle.

[@Alex-pb1pb]

@@sbmotoperformance i finally got around to check this on my bike.. I set the voltage to 600mv, but thats way too low in my eyes. the bike would barely start (not at all without the coldstart) and was then idling very low. the very reason i got the idle screw is to put it a little higher. I thenk set the idle the way i like it and checked the signal and its exactly 666mv :-) Now if i leave it like this can there be problems with the ecu? I havent noticed the problem you described. but what I could imagine is a problem with the ecu thinking the bike is nevery idling (so always getting some throttle) Do you know if thats a problem for the system?

[@human1513]

@@Alex-pb1pb Then you need to adjust the idle screw, which is a throttle plate bypass via a hole in the throttle body to allow more air into the motor at start up and idle only. The reason for this idle screw as KTM calls it is so the bikes will run lean to pass the emissions requirements. It truly is an air bypass screw not an idle speed screw as it progessively (as the screw is turned) opens and closes the bypass passage. Each year 2019, 2020, 2021 & 2022 all seem to have the KTM "idle screw" set at a diiferent # of turns out. Meaning each year has a different set turns out.

[@dmorgan3244]

Does the setting of the air bypass screw affect the TPS voltage?

[@sbmotoperformance]

No, the air bypass screw has Zero affect on the TPS voltage.

[@dmorgan3244]

@@sbmotoperformance Thanks for the reply

[@glowiever]

how could turning the idle screw affects the voltage reading of the tps? 🤔

[@steveboardman9103]

By turning the idle screw you are moving the throttle cam and very slightly opening the butterfly valve inside the throttle body. The throttle positioning sensor's job is to electronically monitor the throttle position and send voltage signals to the ECU. At closed throttle position the voltage is very low, and wide open throttle the voltage is high. By turning the idle screw you are essential increasing voltage ever so slightly. These are just base line setting and we do see some bikes that need to be way outside this baseline range to run right.

[@glowiever]

@@steveboardman9103 I did a test an hour ago on my motorcycle. on that bike the idle screw merely adjust the airway at idle position, and doesn't affect the voltage reading of the tps at all.

[@steveboardman9103]

@@glowiever then I am guessing you are adjusting the air screw, which is the large flat blade screw on the side of the throttle body? The idle screw is a modification that can be installed and it is on the bottom of the throttle body. It is not present on a stock TPI bike unless you install it. Watch the video and you will see what I am talking about.

[@glowiever]

@@steveboardman9103 ah yes the manual mentioned it as idle air screw.

[@fullthrottleahead.]

Quite interesting that stock TPS value is around 12.9~13.4% and it can be converted into around 650mv. Isn't RPM is too low if TSP voltage set near 580~600mv?

[@sbmotoperformance]

Most bikes from 2018 - 2021 will perform best at 600mv. We have found quite a few 2022 that need to be much higher for some reason. The goal is to set each bike to where the off idle throttle response feels good and there is no stalling.

[@rickogas5199]

@@sbmotoperformance thanks for this video and the video that describes removing throttle body and installing idle screw mod. I have a new to me 2022 300xcw TPI that I installed a Rekluse 4.0 on. It dies going down steep hills when I'm trying to coast. On my 2018 300xcw carb bike, no problem, just turn idle up. On my TPI, looks like I need to install the idle screw mod.

[@harleyosterlund5796]

What is a wake up dongle and where can I get one?

[@steveboardman9103]

The wake up dongle comes with the bike in a little spare parts pouch. YOU can order one from the dealer or you can use a wire or staple to short between the two pin holes at the bottom of the connector.

[@harleyosterlund5796]

Ok I figured that out and my reading is 549 and when I turn the air bypass screw it doesn’t change the millivolt reading at all?

[@harleyosterlund5796]

Oops I just realized you are adjusting the idle screw witch I don’t have I guess I’ll order one from Jeff slavens. Now that I’ve moved the air bypass how do I know where to put that? Sorry for bugging you. Best video I’ve found zero info in manual

[@steveboardman9103]

@@harleyosterlund5796 We sell the idle screw on our web site a sbmotoperformance.com

[@codyjoseph44]

What is the stock setting?

[@mihaidobrescu7430]

On a '21 GG EC 300 stock was .606 mv

[@DMC-179]

@@mihaidobrescu7430 how many turns your bypass-airscrew is out originally?

[@ollie6512]

I am having a hanging idle issue. It was much worse before I changed my fuel filter! It was very blocked. Still have a little hang though. Could this be the reason why? My idle screw is set to 1500rpm and air screw out 0.5 turns. kzbin.info/www/bejne/anm3gnaZgruab8k

[@sbmotoperformance]

The hanging idle is typically caused by the idle screw being turned in too far and the TPS voltage reading is too high. Forget about setting the RPM's. Set the voltage correctly and your hanging idle will go away. We set most bikes at 600mv. Every once in a while we see an odd ball bike and it's voltage needs to be set way outside the normal range. Most bikes work best at 600mv.

[@ollie6512]

@@sbmotoperformance thanks a lot. What starting point would you suggest for the air screw? I have a 2019 KTM 250 exc

[@sbmotoperformance]

@@ollie6512 Depends on several factors. Stock or TSP kit? Elevation? Typically for the 2018-2019 250, you can run anywhere from 0.5 to 1.5 turns out from fully seated on the air screw.

[@ollie6512]

@@sbmotoperformance completely stock. I'm running anywhere from sea level to 1000 feet. I live on the cost do mainly see level

[@sbmotoperformance]

@@ollie6512 I would do a TSP power kit with medium comp head if you really want a well running dirt bike. Massive difference. Those stock '18 & 19's left a lot on the table.

[@Huda88754]

My bike won't idle with those ranges

[@sbmotoperformance]

Do you have a TSP power kit installed?

[@Huda88754]

@@sbmotoperformance no its just factory standard with and idle screw added

[@sbmotoperformance]

@@Huda88754 Roger that. These settings are best the TSP Power Kit. Try setting at 600 mv and turn out the air screw until you get a nice low idle.

[@Huda88754]

@@sbmotoperformance thanks ill try that now

[@sbmotoperformance]

@@Huda88754 These setting will require the cold start button to be used for at least 2 minutes when starting a cold bike. Once the bike warms up, you can turn the cold start off and the bike should maintain a nice low idle.

[@danschultz3910]

All you did is adjust idle, you didnt adjust tps at all

[@myronstambaugh761]

In the olden days, didn't we adjust idle speed with our ears? No need for a meter. All you really did in this video is adjust idle speed to a specified rpm based on voltage, yes? Now, adjusting the voltage sent by the TPS for a given idle speed, that is a deeper question, and much argued for its value.

[@southbaymotoperformance9127]

Yeah, not really. We are not concerned with idle RPM. We are concerned with TPS voltage as that is what sync's the throttle position with the fuel map, and if you are outside of a specified rage, you will have some running issues. Too high of voltage causes a hanging idle. Too low can cause a lean bog. That cannot be done with your ear. Please note that this is for a standard TPI. When adding a TSP injection relocation kit (IRK) the procedures for setting the TPS is different since the IRK tune changes the timing and phasing of the injectors based on throttle position and RPM. How we set the TPS voltage for the IRK is quite different.

[@myronstambaugh761]

@@southbaymotoperformance9127 What I saw in your video was you connect a meter to read the voltage from the TPS then adjust that reading upward by TURNING THE IDLE SPEED SCREW. You didn't change the voltage with regard to the butterfly valve (air) at all. You only increased the idle speed. Yes, the voltage went up. It goes up when you open the throttle, as you demonstrated earlier in the video. Did I miss it? Did you loosen the screws on the TPS and rotate it? If you only turned the idle speed screw you didn't adjust the TPS at all. You just adjusted the idle speed. Something you could have done with your ear.