Coming from 35 years of Fuel Injection experience on Vehicles, the Cold start valve is used when cold because the the coolant temperature sensor is telling the computer to enrich the mixture, so more air is needed when the engine is cold, plus adds a higher idle to help the warm up cycle. Not arguing with you just clarifying that it is running richer when cold.
You are absolutely correct. By not using the cold start button when the engine is cold (owners manual says below 50 degrees), the engine will run rich and is more likely to foul a spark plug.
Thank you Jeff for the informative video. I just completed the removal of the set screw and replaced it with your idle screw on my 19 300 XCW TPI. The process of the throttle body removal (with all the electronics) had me spooked But I dove in and found it's not difficult. Total time was 2 hours, of which a lot of time was spent cleaning areas of the bike I usually cannot get to... For the set screw removal, I set a timer for 2 min, then put the heat to the back side of the screw, the lock tight bubbled after 90 seconds. With a T10 torx tool, after the 2 min of heat, the set screw turned easily for 1/2 of a turn then got tight. Another 20 seconds of heat, and it came out easily. After a cooling and cleaning the idle screw was installed, and the air screw was set at 1/2 turn and the idle was tuned to my liking. I'll make the final air screw adjustment on my next ride. Once again thanks for the video, its much appreciated.
You can solve a lot of the tps issues by installing the GET ECU. Yes it’s expensive but it fixed all the driveability issues on my bike. You can set the throttle stop anywhere you want and there’s a function in the GET that lets you zero the tps. Right now I’m 530(arbitrary GET tps reading) and 1/2 turn out on the air screw. Not sure I need to use the air screw at all and might just close it
Just finished mine. Super easy. 1.5 min on the propane set at lowest level. I did have to run a tap through my threads though, but went in easy and runs SO much better at idle and just cracked. Thanks Jeff!!!
I just did mine, 2019 300 TPI, followed Jeffs instructions, I used a big magnifying glass while wife shined my surefire into the gap, was able to get a great view with my old man eyes and see it was a 2.5 mm hex. I applied heat with a standard propane torch for about a min then tested with the hex, the screw moved but felt a bit tight so I hit it with 15 second more heat,, screw came out easy then so 1 .5 minutes heat with the torch turned almost all the way down gets you there. Any questions ask below.
There is an option to Zero in the TPS using the ECU plug, if the butterfly valve is slightly open (because of the new screw) and you reset the TPS how does the affect the fuel / air ratio.
that is perfect for high elevation riders! always found it weird to use the air screw as your idle. now that I can change the idle by opening the butterfly a bit, should make it much easier to ride in higher elevation and start it. then when I am riding above 10k+ I can just use the air screw to let more air in, the way it should have been
My 2020 300XC-W has the 2.5MM set screw. I verified this with light, a magnifying glass and reading glasses. I am at a similar elevation to Jeff and now have the air screw just about 3/4 of a turn out from seated. The dealer had the screw at almost 4 turns out and it barely idled. I used regular propane (had no mapp gas) and a new 2.5MM allen bit. I heated the TB 3+ minutes before it finally let loose. All the while I kept hearing Jeff's voice in my head telling me not to mess it up! Once that screw started moving, it was a very happy time.
Jeff, Can that mod cause crankshaft bearing damage? I am asking you that because, if from factory bike cames lean mixture and we change and make it rich, that injections will give more fuel and air/oil mix will be the same, so more fuel will go to crankshaft bearing holl and there will be more fuel as air/oil. I think you understand logic what I am asking you. so If you think about that please let me know. Thanks,
These "Jeff Slavens" videos are CRAZY good. Not only am I learning how to make the bike better with his little one off custom pieces, I'm actually learning about this throttle body and how it was designed to work and its shortcomings as well. Thanks a ton Mr. Slavens. I like this idle screw. So I guess then I can adjust my air screw here just like I would my old Keihn carb then? Thats crazy how you've been able to reduce it from 1 1/2 turns out to only 1/16th out. Curious to know what rpms you have at 1/16th out on the air screw and 4 1/2mm between the pulley stop? Sid
Sid, that video was on my 2019 300. 1/16th works on that bike and the idle is corrected with the Mule idle screw. The `20-21 models like the air screw around 3-4 turns out.
@@slaverace1 Sir, is the "Mule idle screw" for my 21' still a viable option then? I like the ability to be able to adjust the pulley to my liking. Also, for the 20-21, will the gap at the pulley and set screw still be 4.5mm? Thanks a again sir and have a great holiday and enjoy the family. Sid
i am a new rider that experienced a first dirt bike ride last year on an KDX and liked so much i when to a dealer and got a new TPI. The bike ran great for the first 10 hours then idle sucked, cold start took several attempts then someone showed me another video about the idle screw adjustment, at 20 hours idle was a bit low again and i did not want to deal with taking the cover off with a hot pipe and adjusting it again so i purchased the Slavens screw in this video. Removing the OEM screw in my case did not required any heating, but i am shore some locktite still in there because the slavens screw cannot be adjusted by hand only with a wrench which is fine with me. Great Idea. Now my issue... leaving the air screw out one and a half turns to factory specs then using the screw to adjust the idle works ok for 3/4 of a turn anything over causes crazy pipe bang making the bike want to move when breaking. Have anyone had this issue ? its the same Sound as this guy reported but hes has not done anything to the bike. ruclips.net/video/E4pAqE0aIIg/видео.html
Im having the same pipebang. Needed to screw the airscrew out almost 2 1/2 turn for the bike to not stall at idle. Just installed the Slavens and hoping this will help, but haven't had the chance to try it yet? So did you get rid of the bang? Seems like Slavens and "that other guy" on youtube, means you should almost completely close the aircsrew.
ciao Fabiano, volevo sapere se anche tu hai fatto questa modifica sulla tua moto e come ti trovi... la vite di regolazione la devi prendere la loro oppure si può usare una vite standard?
There's another video of a guy that is adjusting that idle screw by only taking the cover off. His screw turned. Are they using permanent lock tight now?
Hy, Mrs. Jeff Slaves. First of all you are doing a great job on the how-to videos, it help's a lot and they are really detailed, keep it that way! I would like to have a few questions regarding to KTM/Husky tpi engines, maybe these answers can be covered in next video too.. I got a 2018 husky 300 tpi, and I really like the bike, thee feeling of it how perfect is the response of it and the linear power delivery, but a lot of guys say as you mention it is running quite lean comparing to the carb models. Have you got any tips how can be this lean mixture problem improved to give the engine a longer life? I read and heard at some places the following things, what is your opinion about theese, or can you suggest any other methods? - opening the airbox helps (i did this one, i think it affected pozitiv the runing of the engine) - premixing some oil in the fuel in a ratio of 100ml in a full tank - aprox 9l - i didn;t try this, I'm afraid it will mess up the fuel filters and the injectors - removing the thermostat and install the fan on manual switch to mislead the ecu's engine heat sensor, this way it tells the system to add more oil in the mixture because the engine temp reaches to the operating temperature slower - do this idle screw modification can increase the mixture ratio? I'm planning to do this in the next days Also if you can give any further maintenance tips to keep the bike last longer it would be appreciated :)
Hello: You've obviously read way too much internet garbage. You forgot to turn on the BS filter. -Opening the air box makes them leaner. You went the wrong direction -Adding oil to the fuel tank does NOTHING to improve lubrication. The injectors are in the transfer ports and the injected fuel goes directly to the top of the piston and never reaches the piston skirts or the bearings. The Snakeoil Salesman that sells the filter is a crook. - Thermostat and fan information - You really dug deep to find this crap information - TOTALLY WRONG - The adjustable idle screw allows the air screw to be independently adjusted - Want it to last longer? Install a GET ECU to correct the lean fueling.
2.5 mm allen for my 2020 TX 300i. Wasn't too bad to remove. New screw arrives on Saturday. Tried some of that Bob Smith Industries UN-Cure stuff, but that didn't work. Small Benzomatic for about a minute did the job.
Might want to mention how you need to use the wake up dongle before restarting the bike to bleed air out of the oil hose. I didn't do that and now I have a strange knocking in my engine. It's a MAJOR final part of this operation and now I'm screwed because I wasn't aware I needed to do that. Probably doing an entire top-end rebuild now which I'm not too happy about.
I highly recommend using focused heat by heating the tip o the torx wrench to cherry red, insert it into the idle screw, and repeat 3-4 times. the heat will transfer and melt the glue. The torx will loose its hardened properties, but a small price as a sacrificial aid to removing the screw without risk of melting the fragile components within the Throttle body. It works well, but you will need two torx drivers Suggestion from :- Stuart Hughes Wales G.B.
My 20 XC decided to stop idling. It ran perfect at idle for the first 25 hours then decided no more. Air screw was out 4.5 turns from the factory. Did this mod and results are interesting. Idle speed is very inconsistent now. Sometimes it will idle very quickly at startup, others it will barely get along enough to keep from dying. Initially set screw with calipers then increased the idle speed so that it is reasonable on average. It seemed happiest at about 1/4 turn out on the air screw. Was getting hanging idle with any more lean. Got back from my first ride with it today. After washing and letting dry for awhile, started it up to ride it to my truck and it died. Figured something shorted and blew a fuse from washing. All fuses were good, fuel pump cranked over, everything seemed fine. decided to change spark plug (put in a fresh one with this mod) and it was fouled. Put in a new one and it started, but ran pretty bad. I was roughly a quarter turn out on the air screw so I guess I will try a half turn next time and see. With my bike being so inconsistent I feel there may be another issue. Possibly an electrical component or sensor. Tpi has not been good to me so far
The video was made a LONG time ago and is for 2018-19 models that were lean from the factory. 2020 and 2021 models are RICH. Your air screw should be set at 4 - 4 1/2 turns out. Your current setting is extremely rich.
@@slaverace1 Hello Jeff. I also just did the mod to my 2020 300 XCW 103 hr. at 4 1/2 out on the air screw I also am having same results as Marshall. It seems idle hang up stops around 2 1/2 to 3 turns out . worried now it will be to rich ? can you give some insight please?
Will you do any video on the idle settings or have comments on the 17-19 KTM/Husky that have the Throttle body with the Red Idle Screw and the Yellow Cold Start Screw? I hear more and more people that are turning yellow all the way, adjust the Red idle screw and do not even use the cold start any more.
I'll put it in the queue BUT what you mention seems unnecessary. I've never used the cold start on any of my 4 strokes. I just hit the button and they start up.
After adding all these nice to/must have little parts you make to my new bike, this is probably as close to a "works" bike I'll ever have. I just received my Quickstart Mule capacitor the other day. Thank you.
Just a question and i hope you can take away my doubts: You say: "the idle screw changes the fuel-air ratio" at 15:21 in your video. But the TPI injects the fuel directly into the Transfer Ports. So how is that screw changing the fuel-air ratio? I thought that the throttle body did not do anything else then changing the amount of air. Please can you explain a little bit?
As you correctly stated, the tpi injects FUEL into the transfer ports. It does NOT inject air which comes through the throttle body. Adjusting the AIR screw on the side of the throttle body adds to or reduces the amount of air.
i dont understand how you guys have so many problems with tpi bikes my bike has been thro so much suffering and ive never had a problem it has 65 hours(18 exc 300 tpi). the only problem i have its that it never smokes when its running and i want to know if its normal.
So once all installed you should start the bike with air screw closed. And adjust idle via Newley installed bolt and once idle is set adjust air screw to get engine performance dialed in
Thank you for the instruction. Just installed your idle screw on my '21 Gas Gas ex300...any recommendations on air screw settings at sea level? Still recommended to be closed to nearly closed on the '21's? Thanks again.
I just bought a 2022 300 xcw haven’t taken it out yet. Should I do idle screw mod before I even ride it ? It’s a clean work area. I bought your screw already.Did they fix problem? What would the air screw adjustment be or is it too early to tell? Tks a bunch. I’m one of Max’s buddies from Vegas
Max's buddy? You need a new friend, ha! Kick the old fart in the pants for me. You should always put on some miles in bone stock condition before making any changes. The 22s need the idle screw because they idle too slow and tend to die on downhills and in tight conditions.
Quick question… in another video I watched a guy said that you must get out all of the air in the oil injection system before reattaching the throttlebody because you may have air in the system and it will not inject oil. Is this true?
Hello: Your owner's manual describes how to prime the oil pump and I also explain it in one of my videos. If there i just a bubble or two in the line they will pass through quickly without priming it BUT if the pump is full of air you must use the priming procedure.
Hi Jeff, quick question. Once you remove the throttle body & if your gap with the stock screw is already at 4.5mm, is the mod still needed? If that gap is set at 4.5mm can you just go ahead and adjust the airscrew? Cheers
Jeff Slavens ok cool. Will this mod help with 1/4-1/2 throttle bogging? My bike (2019 300) is fine on the idle & starting but the roll on bogging is really starting to become a problem. I appreciate your help & your vids are great!
...so if and when most of us strip it..... what is the best way to remove the screw then? i assume its harden steel and most drill bits wont be able to drill it out so easily
Are you saying most TPI owners are incapable of watching a basic instructional video and tackling a simple job such as this? If you are one of those people in the “most” category, should you really have a set of cutlery, let alone garage tools. To quote President Biden, C’mon man, get real.
Struggeling with "pipe-bang" when I close the throttle. if enginebraking, you can feel the bike pull forward for each bang. Im totally new to two-strokes and dirtbikes in general, so maybe it's supposed to be like this, but it just feels wrong. Will adjusting the AFR (closing the air screw) help cure this?
My KTM 300 exc 19 had a very low idle but it never caused any issues and kept ticking by. But after last Sundays race it won't idle at all. Soon as I take my hand off the throttle it cuts out. But it still starts and rides perfectly. I'm still going to do this mod but surely I must have other issues if it idled before hand. Any ideas?
I have to respectably disagree, the factory screw and the aftermarket idle screw do the exact same function. They both introduce air into the system to increase idle speed, and BOTH create the same lean condition. You kinda talked about it in the video that it doesn't create the lean condition but can you explain how? thanks
He didn't explain that well. The difference is that the idle screw he installs only affects airflow at idle (when you're not touching the throttle). If you use the air screw to up the idle, you're adding air at all throttle openings. Now you're leaner everywhere. What used to be 25% throttle, is now 25% throttle + however much extra air you're getting through the air screw. Basically the argument for this mod is that you can use the idle screw instead, and close the air screw to richen the map (slightly) everywhere which should be a benefit as these bikes are a bit lean. That said, I have a TPI and I'm not going to mess with these screws. I'm going to wait for a better solution (Aftermarket ECU)
You're correct, I over looked that aspect of it. But isn't this mod for starting and idle quality, so in the same throttle closed state, idle/starting they both have the lean condition?
What he also fail to explain is the throttle position between 0% and 2.5% doesn't change the fuel injected. But if you do this mod, throttle at idle will 1-2% (not accurate just example) but rpm will be the same. Therefore as you turn the throttle, more fuel is added at a lower rpm therefore increasing fuel/air ratio
After completing this procedure on my 19 300 XC-W and putting probably 30 hours on the bike I've started to have hanging idle conditions when the bike is hot. Any suggestions on where to start, Jeff?
Mick: Good question. The fueling is a constant supply controlled by the ECU mapping but the air screw makes the air supply variable and that changes the fuel to air ratio.
Sorry, But there are no chances to adjust it with the stock bold? just screw it a little, or it's too short, or lock tide is the problem? Actually I don't know why ktm did bikes so lean, it's cause a lot of problems and a lot of money to repair this.
I used Methylene Chloride and it broke down the Loctite threadlocker after dabbing it with a Q tip for about 15 minutes to keep it wet, then used the T-10 to remove. All done without removing the throttle body from the bike. Could not budge it without this process. Be care Methylene Chloride is a very strong solvent and you should have good ventilation.
Any tips on how to remove the grub screw if the head rounds out? It had a lot of heat in it but it cracked apart before it moved. Tried some dril bits on it but it's very hard.
@@chrissalt8122 same here mate I justed picked mine up from having the grub screw drilled out. People should know Not all come out as easy as in this video.
@@slaverace1 Jeff, I've refreshed lots of top end TPI's with no idle screws and I've never seen a problem with premature piston wear or failure...what data do you have to back up that claim?
KTM and HQV 250s and 300s all use the same throttle body and the TPS can be adjusted if you remove the dowel pins but why do you want to? What are you trying to accomplish?
@@slaverace1 thanks for your reply. Well, I'm having issues with the start and idling so wanted to set everything as factory default to start all the setting over again (I've installed the idle adjuster bolt). I thought the TPS might have been moved in a crash or something so wanted to check, but cannot see the type of dial holes I see in the videos so thought mine is not really adjustable. So far I did not unscrew it to avoid messing up even more....
Do you have a recommended starting point for the air screw setting on the 2020/ 2021 when doing this mod? I know the new ones come stock with the air screw turned out quite a bit further than the 18/ 19 models. Do you still typically only go closed - 1/2 turn out on the 2020 or more like 1 - 1.5?
Ive just done this to my 2020 300 Stock was 3 1/2 turns on the air bypass screw The idle screw set to a nice steady speed, i have got it now set to 1/2 seems nice and crisp but will need a proper ride to finalise
Just did this mod on my 2021 KTM 300 XC TPi today. Stock air screw setting was 4 turns out and stock throttle gap was 4mm. My grub screw was a 2.5mm Allen. I increased the throttle screw to 4.5mm with the Slavens Easy Idle and bumped my air screw back to 3 turns out. Going to test and tune this Friday, will report back with final settings.
I've seen this video so many times and I still don't manage to understand how the air screw adjustment affects the air fuel ratio and the butterfly opening doesn't... I would rather say that's only the air oil ratio that could be affected by the air bypass screw 🤔
I’ve adjusted my power valve adjuster out a turn an now the idle is low and it cuts out, I then adjusted the air screw without knowing and it now runs even worse, I didn’t realise that the idle adjuster is there, hopefully I can set the air screw back an make this mod to increase the actual idle speed slightly now 👍🏻
Since they reworked the idle system this year did you noticed on your 2020 XC-W did that take care of the idle problems that plague the previous TPI models so that this fix will not be needed. Thanks
Хобби
Coming from 35 years of Fuel Injection experience on Vehicles, the Cold start valve is used when cold because the the coolant temperature sensor is telling the computer to enrich the mixture, so more air is needed when the engine is cold, plus adds a higher idle to help the warm up cycle. Not arguing with you just clarifying that it is running richer when cold.
You are absolutely correct. By not using the cold start button when the engine is cold (owners manual says below 50 degrees), the engine will run rich and is more likely to foul a spark plug.
@@alang3991 The cold start, like Stomp went over, richens the mixture. Just like a choke on a carb.
Thank you Jeff for the informative video. I just completed the removal of the set screw and replaced it with your idle screw on my 19 300 XCW TPI. The process of the throttle body removal (with all the electronics) had me spooked But I dove in and found it's not difficult. Total time was 2 hours, of which a lot of time was spent cleaning areas of the bike I usually cannot get to... For the set screw removal, I set a timer for 2 min, then put the heat to the back side of the screw, the lock tight bubbled after 90 seconds. With a T10 torx tool, after the 2 min of heat, the set screw turned easily for 1/2 of a turn then got tight. Another 20 seconds of heat, and it came out easily. After a cooling and cleaning the idle screw was installed, and the air screw was set at 1/2 turn and the idle was tuned to my liking. I'll make the final air screw adjustment on my next ride. Once again thanks for the video, its much appreciated.
You can solve a lot of the tps issues by installing the GET ECU. Yes it’s expensive but it fixed all the driveability issues on my bike. You can set the throttle stop anywhere you want and there’s a function in the GET that lets you zero the tps. Right now I’m 530(arbitrary GET tps reading) and 1/2 turn out on the air screw. Not sure I need to use the air screw at all and might just close it
Just finished mine. Super easy. 1.5 min on the propane set at lowest level. I did have to run a tap through my threads though, but went in easy and runs SO much better at idle and just cracked. Thanks Jeff!!!
I just did mine, 2019 300 TPI, followed Jeffs instructions, I used a big magnifying glass while wife shined my surefire into the gap, was able to get a great view with my old man eyes and see it was a 2.5 mm hex. I applied heat with a standard propane torch for about a min then tested with the hex, the screw moved but felt a bit tight so I hit it with 15 second more heat,, screw came out easy then so 1 .5 minutes heat with the torch turned almost all the way down gets you there. Any questions ask below.
There is an option to Zero in the TPS using the ECU plug, if the butterfly valve is slightly open (because of the new screw) and you reset the TPS how does the affect the fuel / air ratio.
Altering throttle position will open the closed throttle switch and ecu will not run with idle maps anymore.It will run part throttle maps.
For people who live in Australia this isn’t essential but it can be if you ride around 6000ft which not many areas in Aus are.
that is perfect for high elevation riders! always found it weird to use the air screw as your idle. now that I can change the idle by opening the butterfly a bit, should make it much easier to ride in higher elevation and start it. then when I am riding above 10k+ I can just use the air screw to let more air in, the way it should have been
My 2020 300XC-W has the 2.5MM set screw. I verified this with light, a magnifying glass and reading glasses. I am at a similar elevation to Jeff and now have the air screw just about 3/4 of a turn out from seated. The dealer had the screw at almost 4 turns out and it barely idled. I used regular propane (had no mapp gas) and a new 2.5MM allen bit. I heated the TB 3+ minutes before it finally let loose. All the while I kept hearing Jeff's voice in my head telling me not to mess it up! Once that screw started moving, it was a very happy time.
Thanks very helpful step by step was good ! Definitely was taking my time to loosen the screw I didn’t was to strip the head ! Everything worked out !
Jeff, Can that mod cause crankshaft bearing damage? I am asking you that because, if from factory bike cames lean mixture and we change and make it rich, that injections will give more fuel and air/oil mix will be the same, so more fuel will go to crankshaft bearing holl and there will be more fuel as air/oil. I think you understand logic what I am asking you. so If you think about that please let me know.
Thanks,
What size are the tps cover screws, the safety torx ones? I want to replace the safety torx ones. Thanks.
Fantastic video and explanation Jeff. Very good advice on how to heat it without causing damage.
These "Jeff Slavens" videos are CRAZY good. Not only am I learning how to make the bike better with his little one off custom pieces, I'm actually learning about this throttle body and how it was designed to work and its shortcomings as well.
Thanks a ton Mr. Slavens. I like this idle screw. So I guess then I can adjust my air screw here just like I would my old Keihn carb then? Thats crazy how you've been able to reduce it from 1 1/2 turns out to only 1/16th out. Curious to know what rpms you have at 1/16th out on the air screw and 4 1/2mm between the pulley stop?
Sid
Sid, that video was on my 2019 300. 1/16th works on that bike and the idle is corrected with the Mule idle screw. The `20-21 models like the air screw around 3-4 turns out.
@@slaverace1 Sir, is the "Mule idle screw" for my 21' still a viable option then? I like the ability to be able to adjust the pulley to my liking. Also, for the 20-21, will the gap at the pulley and set screw still be 4.5mm?
Thanks a again sir and have a great holiday and enjoy the family.
Sid
i am a new rider that experienced a first dirt bike ride last year on an KDX and liked so much i when to a dealer and got a new TPI. The bike ran great for the first 10 hours then idle sucked, cold start took several attempts then someone showed me another video about the idle screw adjustment, at 20 hours idle was a bit low again and i did not want to deal with taking the cover off with a hot pipe and adjusting it again so i purchased the Slavens screw in this video. Removing the OEM screw in my case did not required any heating, but i am shore some locktite still in there because the slavens screw cannot be adjusted by hand only with a wrench which is fine with me. Great Idea. Now my issue... leaving the air screw out one and a half turns to factory specs then using the screw to adjust the idle works ok for 3/4 of a turn anything over causes crazy pipe bang making the bike want to move when breaking. Have anyone had this issue ? its the same Sound as this guy reported but hes has not done anything to the bike.
ruclips.net/video/E4pAqE0aIIg/видео.html
Im having the same pipebang. Needed to screw the airscrew out almost 2 1/2 turn for the bike to not stall at idle. Just installed the Slavens and hoping this will help, but haven't had the chance to try it yet? So did you get rid of the bang?
Seems like Slavens and "that other guy" on youtube, means you should almost completely close the aircsrew.
In my case it turned out to be a failing oil pump engine eventually seized.
ciao Fabiano, volevo sapere se anche tu hai fatto questa modifica sulla tua moto e come ti trovi... la vite di regolazione la devi prendere la loro oppure si può usare una vite standard?
I just did my 2021 Husky 300. It was easy if you follow these instructions. Mine was a 2.5 mm allen. Thanks for the video Slavens. 😁
There's another video of a guy that is adjusting that idle screw by only taking the cover off. His screw turned. Are they using permanent lock tight now?
Hy, Mrs. Jeff Slaves.
First of all you are doing a great job on the how-to videos, it help's a lot and they are really detailed, keep it that way!
I would like to have a few questions regarding to KTM/Husky tpi engines, maybe these answers can be covered in next video too..
I got a 2018 husky 300 tpi, and I really like the bike, thee feeling of it how perfect is the response of it and the linear power delivery, but a lot of guys say as you mention it is running quite lean comparing to the carb models.
Have you got any tips how can be this lean mixture problem improved to give the engine a longer life? I read and heard at some places the following things, what is your opinion about theese, or can you suggest any other methods?
- opening the airbox helps (i did this one, i think it affected pozitiv the runing of the engine)
- premixing some oil in the fuel in a ratio of 100ml in a full tank - aprox 9l - i didn;t try this, I'm afraid it will mess up the fuel filters and the injectors
- removing the thermostat and install the fan on manual switch to mislead the ecu's engine heat sensor, this way it tells the system to add more oil in the mixture because the engine temp reaches to the operating temperature slower
- do this idle screw modification can increase the mixture ratio? I'm planning to do this in the next days
Also if you can give any further maintenance tips to keep the bike last longer it would be appreciated :)
Hello: You've obviously read way too much internet garbage. You forgot to turn on the BS filter.
-Opening the air box makes them leaner. You went the wrong direction
-Adding oil to the fuel tank does NOTHING to improve lubrication. The injectors are in the transfer ports and the injected fuel goes directly to the top of the piston and never reaches the piston skirts or the bearings. The Snakeoil Salesman that sells the filter is a crook.
- Thermostat and fan information - You really dug deep to find this crap information - TOTALLY WRONG
- The adjustable idle screw allows the air screw to be independently adjusted
- Want it to last longer? Install a GET ECU to correct the lean fueling.
2.5 mm allen for my 2020 TX 300i. Wasn't too bad to remove. New screw arrives on Saturday. Tried some of that Bob Smith Industries UN-Cure stuff, but that didn't work. Small Benzomatic for about a minute did the job.
We've had a lot of positive feedback about the uncure. Guys leave it on overnight.
Might want to mention how you need to use the wake up dongle before restarting the bike to bleed air out of the oil hose. I didn't do that and now I have a strange knocking in my engine. It's a MAJOR final part of this operation and now I'm screwed because I wasn't aware I needed to do that. Probably doing an entire top-end rebuild now which I'm not too happy about.
I highly recommend using focused heat by heating the tip o the torx wrench to cherry red, insert it into the idle screw, and repeat 3-4 times. the heat will transfer and melt the glue. The torx will loose its hardened properties, but a small price as a sacrificial aid to removing the screw without risk of melting the fragile components within the Throttle body. It works well, but you will need two torx drivers
Suggestion from :-
Stuart Hughes
Wales
G.B.
Sorry 2.5mm Allen was the correct tool following the torx
My 20 XC decided to stop idling. It ran perfect at idle for the first 25 hours then decided no more.
Air screw was out 4.5 turns from the factory.
Did this mod and results are interesting. Idle speed is very inconsistent now. Sometimes it will idle very quickly at startup, others it will barely get along enough to keep from dying. Initially set screw with calipers then increased the idle speed so that it is reasonable on average. It seemed happiest at about 1/4 turn out on the air screw. Was getting hanging idle with any more lean.
Got back from my first ride with it today. After washing and letting dry for awhile, started it up to ride it to my truck and it died. Figured something shorted and blew a fuse from washing. All fuses were good, fuel pump cranked over, everything seemed fine. decided to change spark plug (put in a fresh one with this mod) and it was fouled. Put in a new one and it started, but ran pretty bad. I was roughly a quarter turn out on the air screw so I guess I will try a half turn next time and see. With my bike being so inconsistent I feel there may be another issue. Possibly an electrical component or sensor. Tpi has not been good to me so far
The video was made a LONG time ago and is for 2018-19 models that were lean from the factory. 2020 and 2021 models are RICH. Your air screw should be set at 4 - 4 1/2 turns out. Your current setting is extremely rich.
@@slaverace1 good to know.
Any idea on why my idle issue started occurring or things to check?
@@slaverace1 Hello Jeff. I also just did the mod to my 2020 300 XCW 103 hr. at 4 1/2 out on the air screw I also am having same results as Marshall. It seems idle hang up stops around 2 1/2 to 3 turns out . worried now it will be to rich ? can you give some insight please?
Will you do any video on the idle settings or have comments on the 17-19 KTM/Husky that have the Throttle body with the Red Idle Screw and the Yellow Cold Start Screw? I hear more and more people that are turning yellow all the way, adjust the Red idle screw and do not even use the cold start any more.
I'll put it in the queue BUT what you mention seems unnecessary. I've never used the cold start on any of my 4 strokes. I just hit the button and they start up.
After adding all these nice to/must have little parts you make to my new bike, this is probably as close to a "works" bike I'll ever have. I just received my Quickstart Mule capacitor the other day. Thank you.
Just a question and i hope you can take away my doubts: You say: "the idle screw changes the fuel-air ratio" at 15:21 in your video. But the TPI injects the fuel directly into the Transfer Ports. So how is that screw changing the fuel-air ratio? I thought that the throttle body did not do anything else then changing the amount of air. Please can you explain a little bit?
As you correctly stated, the tpi injects FUEL into the transfer ports. It does NOT inject air which comes through the throttle body. Adjusting the AIR screw on the side of the throttle body adds to or reduces the amount of air.
i dont understand how you guys have so many problems with tpi bikes my bike has been thro so much suffering and ive never had a problem it has 65 hours(18 exc 300 tpi). the only problem i have its that it never smokes when its running and i want to know if its normal.
So once all installed you should start the bike with air screw closed. And adjust idle via Newley installed bolt and once idle is set adjust air screw to get engine performance dialed in
The air screw usually ends up between 1/4 and 1 turn out.
How about on a 2020 300 XC W? The Idle air bypass screw gets GENERALLY turned counterclockwise about how much after installing your screw?
Thanks!
Hi Jeff, Would the Australian delivered KTM TPI's be effected? My dealer tells me he has loaded the rich map.
Hi, love your Channel. I have a 2018 300 exc European... should i update the ECU to 2019 map? I heard that the 2018 map is too lean
Thank you for the instruction. Just installed your idle screw on my '21 Gas Gas ex300...any recommendations on air screw settings at sea level? Still recommended to be closed to nearly closed on the '21's? Thanks again.
I just bought a 2022 300 xcw haven’t taken it out yet. Should I do idle screw mod before I even ride it ? It’s a clean work area. I bought your screw already.Did they fix problem? What would the air screw adjustment be or is it too early to tell? Tks a bunch. I’m one of Max’s buddies from Vegas
Max's buddy? You need a new friend, ha! Kick the old fart in the pants for me. You should always put on some miles in bone stock condition before making any changes. The 22s need the idle screw because they idle too slow and tend to die on downhills and in tight conditions.
Hi, is there a full open throttle stop screw? So the butterfly does not over open and actually close for not stopping ?
No
Quick question… in another video I watched a guy said that you must get out all of the air in the oil injection system before reattaching the throttlebody because you may have air in the system and it will not inject oil. Is this true?
Hello:
Your owner's manual describes how to prime the oil pump and I also explain it in one of my videos. If there i just a bubble or two in the line they will pass through quickly without priming it BUT if the pump is full of air you must use the priming procedure.
Hi Jeff, quick question. Once you remove the throttle body & if your gap with the stock screw is already at 4.5mm, is the mod still needed?
If that gap is set at 4.5mm can you just go ahead and adjust the airscrew?
Cheers
The 4.5mm gap is just a starting point for the screw.
Jeff Slavens ok cool. Will this mod help with 1/4-1/2 throttle bogging? My bike (2019 300) is fine on the idle & starting but the roll on bogging is really starting to become a problem. I appreciate your help & your vids are great!
@@benpeck8592
Yes
...so if and when most of us strip it..... what is the best way to remove the screw then? i assume its harden steel and most drill bits wont be able to drill it out so easily
Most don't strip it. If you take your time, heat it and use the correct tool, it will come out easily.
Are you saying most TPI owners are incapable of watching a basic instructional video and tackling a simple job such as this? If you are one of those people in the “most” category, should you really have a set of cutlery, let alone garage tools. To quote President Biden, C’mon man, get real.
Struggeling with "pipe-bang" when I close the throttle. if enginebraking, you can feel the bike pull forward for each bang. Im totally new to two-strokes and dirtbikes in general, so maybe it's supposed to be like this, but it just feels wrong. Will adjusting the AFR (closing the air screw) help cure this?
The pipe bang is very annoying and not acceptable. Yes, the screw is the first step to correcting that issue. Install the screw and shut off the air.
My KTM 300 exc 19 had a very low idle but it never caused any issues and kept ticking by. But after last Sundays race it won't idle at all. Soon as I take my hand off the throttle it cuts out. But it still starts and rides perfectly. I'm still going to do this mod but surely I must have other issues if it idled before hand.
Any ideas?
I have to respectably disagree, the factory screw and the aftermarket idle screw do the exact same function. They both introduce air into the system to increase idle speed, and BOTH create the same lean condition. You kinda talked about it in the video that it doesn't create the lean condition but can you explain how? thanks
He didn't explain that well. The difference is that the idle screw he installs only affects airflow at idle (when you're not touching the throttle). If you use the air screw to up the idle, you're adding air at all throttle openings. Now you're leaner everywhere. What used to be 25% throttle, is now 25% throttle + however much extra air you're getting through the air screw. Basically the argument for this mod is that you can use the idle screw instead, and close the air screw to richen the map (slightly) everywhere which should be a benefit as these bikes are a bit lean. That said, I have a TPI and I'm not going to mess with these screws. I'm going to wait for a better solution (Aftermarket ECU)
You're correct, I over looked that aspect of it. But isn't this mod for starting and idle quality, so in the same throttle closed state, idle/starting they both have the lean condition?
What he also fail to explain is the throttle position between 0% and 2.5% doesn't change the fuel injected. But if you do this mod, throttle at idle will 1-2% (not accurate just example) but rpm will be the same. Therefore as you turn the throttle, more fuel is added at a lower rpm therefore increasing fuel/air ratio
Did you delete/remove the other video involving the air screw?
Yes
After completing this procedure on my 19 300 XC-W and putting probably 30 hours on the bike I've started to have hanging idle conditions when the bike is hot. Any suggestions on where to start, Jeff?
Richen (clockwise) the air screw.
Jeff Slavens okay I will richen it up. Thank you for the response!
Hello Jeff love the videos I should be getting my 2020 xc 300 soon and am wondering if I should order this right now!
Don't know. 20s are not here yet.
How does the air screw effect the fuel when there is no fuel in the throttle body?
Mick:
Good question. The fueling is a constant supply controlled by the ECU mapping but the air screw makes the air supply variable and that changes the fuel to air ratio.
Do you need to prime the oil pump or anything after re attaching?
yes you do. KTM call's it TIME the oil pump.
Great question. Thanks.
Sorry, But there are no chances to adjust it with the stock bold? just screw it a little, or it's too short, or lock tide is the problem? Actually I don't know why ktm did bikes so lean, it's cause a lot of problems and a lot of money to repair this.
It’s easy to adjust the stock bolt. Just use the right tool and pliers to get some force. I didn’t even have to remove the throttle body
Would acetone or any other solvent dissolve the thread locker?
I used Methylene Chloride and it broke down the Loctite threadlocker after dabbing it with a Q tip for about 15 minutes to keep it wet, then used the T-10 to remove. All done without removing the throttle body from the bike. Could not budge it without this process. Be care Methylene Chloride is a very strong solvent and you should have good ventilation.
@@tedcampbell25 Do you got a link to this?
Any tips on how to remove the grub screw if the head rounds out? It had a lot of heat in it but it cracked apart before it moved. Tried some dril bits on it but it's very hard.
Chris, Sorry your throttle body is being difficult. Sounds like you need to send it to us and our machinist will remove it.
Jeff Slavens yes thanks I would if I was in the USA . Looking for a good machinist local to me in the U.K.
@@chrissalt8122 what was the outcome here. I've heated mine up but it won't move.
EnduroEMTB-RideWales I had to have it drilled out by a local machinist.
@@chrissalt8122 same here mate I justed picked mine up from having the grub screw drilled out. People should know Not all come out as easy as in this video.
So what is the consequence of NOT doing this and staying with the stock settings? I'm not clear on what happens after all this work.
The consequence of not installing it is the lean condition that causes poor performance, premature piston wear and failure.
@@slaverace1 I need to do this on my 2020 xcw ktm 300 erzbergrodeo????
@@slaverace1 Jeff, I've refreshed lots of top end TPI's with no idle screws and I've never seen a problem with premature piston wear or failure...what data do you have to back up that claim?
Hi Jeff, is the TPS in the Husq 250i adjustable as in the 300s?
KTM and HQV 250s and 300s all use the same throttle body and the TPS can be adjusted if you remove the dowel pins but why do you want to? What are you trying to accomplish?
@@slaverace1 thanks for your reply. Well, I'm having issues with the start and idling so wanted to set everything as factory default to start all the setting over again (I've installed the idle adjuster bolt). I thought the TPS might have been moved in a crash or something so wanted to check, but cannot see the type of dial holes I see in the videos so thought mine is not really adjustable. So far I did not unscrew it to avoid messing up even more....
Do you have a recommended starting point for the air screw setting on the 2020/ 2021 when doing this mod? I know the new ones come stock with the air screw turned out quite a bit further than the 18/ 19 models. Do you still typically only go closed - 1/2 turn out on the 2020 or more like 1 - 1.5?
Ive just done this to my 2020 300
Stock was 3 1/2 turns on the air bypass screw
The idle screw set to a nice steady speed, i have got it now set to 1/2 seems nice and crisp but will need a proper ride to finalise
Just did this mod on my 2021 KTM 300 XC TPi today. Stock air screw setting was 4 turns out and stock throttle gap was 4mm. My grub screw was a 2.5mm Allen. I increased the throttle screw to 4.5mm with the Slavens Easy Idle and bumped my air screw back to 3 turns out. Going to test and tune this Friday, will report back with final settings.
Tom, 3 turns out is probably too rich.
I need to do this on my 2020 ktm 300 xcw erzbergrodeo???
You don't have to if it runs good.
do we close the air screw once we install the screw?
I have a 2021 ktm 250 xcw
No, not on `20-21 models which usually need the air screw set between 3.5 and 4.5 turns out.
Just needed this information and there it is. Thanks Jeff
@@slaverace1 Hi Jeff , do we need to use the wake up dongle to recalibrate the pump after doing this and if so how do we do that ?
hi, how are you with the s3 header?
Our proprietary Slavens Mule S3 heads are excellent.
I've seen this video so many times and I still don't manage to understand how the air screw adjustment affects the air fuel ratio and the butterfly opening doesn't...
I would rather say that's only the air oil ratio that could be affected by the air bypass screw 🤔
I’ve adjusted my power valve adjuster out a turn an now the idle is low and it cuts out, I then adjusted the air screw without knowing and it now runs even worse, I didn’t realise that the idle adjuster is there, hopefully I can set the air screw back an make this mod to increase the actual idle speed slightly now 👍🏻
I think that is a HOT START button to lean the mixture during hot starts.
Why not just torch the TORX wrench itself so it’s only heating the screw? Wear some welders gloves after it’s hot.
That might work. There are many ways to skin a cat.
i think if you fully close the air screw -the motor will have smaller amount of OIL..because on that TPI bikes oil goes in motor only with air flow
Sorry, you are incorrect. There is a constant vacuum from the back of the cylinder and that operates the pump.
is that a S3 head?
Yes, with our proprietary insert design. Fair price, high quality, excellent performance and no scammy trenches.
After installing the screw my bike is running better with the air screw closed.it is normal?
There is no “normal”.
@@slaverace1 should i leave it like this?thank you!
@@66AGW
Set it wherever it works.
strange, I have the same issue, and it still has a hanging idle... wtf?
GREAT Video!!!
On my 2019 TPI the Screw have no T10
Some bikes have torx and others have a 2.5 allen.
The 2,5 Allen ist to small and the 3,0 Allen is to big.
I have no Idea.
Since they reworked the idle system this year did you noticed on your 2020 XC-W did that take care of the idle problems that plague the previous TPI models so that this fix will not be needed. Thanks
2020's still idle too low. Especially with the clutch drag.
Front Range Enduro MTB What is the fix for the clutch drag?
What rad braces are those?
The absolute best. Bullet Proof Designs slavensracing.com/shop/radiator-guards-bullet-proof-designs-ktm/
That’s the cat’s ass, right there!
You're scaring me maybe I should just keep my old bike.
Great video, probably a bit much for the average home gamer to grasp and perform but I get it.
Man I wish Jeff was my neighbor
I can't believe this bike is about the same price as the 450 SX-F.