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What is correct Idle setting on 17 300xcw at sea level

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First let me say this. I love my ktm.

 

I have owned a bunch of Japanese bikes over the years, but the ktm is one of the most refined bikes ever made IMHO. What is the ideal idle setting for riding at sea levl. I've had it set at 2000 -2100rpms runs like a champ. At 14-1500rpms it seems to chug and runs rough. Give it the gas and it sings. There are 2 hrs on the engine. This seems like a dumb question, but I had to buy an after market tach. To know the rpms.

 

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Idle is idle, set it enough so it can run on it own. If you grab some throttle and it hesitates etc, this has nothing to do with idle. You need to be adjusting the Air screw. The air screw is what gives you the transition from pilot to needle without it stumbling.

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What he said. Set pilot so you grab throttle and do a full, quick as can rev from idle to high speed with no hesitation and bogging. In neutral 

then set idle where you and the bike are happy. 

Many are struggling getting the Mikuni to run properly with stock jetting specs 

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Thanks RMK and tiger, you answered my question perfectly. There is no bogging when I grab throttle. I was just trying to conform to owners manual for setting idle rpms. I now realize that factory settings are just a baseline. My bike  idles best around 2000 rpms.  so that makes me happy now and the bike is always happy.:ride:

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Glad you got it where you like it. It’s really preference. I run a little higher idle... because when I’m racing and going into some tight crap, I don’t want my bike killing on me... higher idle makes it not as easy to kill.

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I'm the same way, I want to know there's constant power on demand with a flick of the throttle . Thanks again.

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22 hours ago, tigertiger said:

What he said. Set pilot so you grab throttle and do a full, quick as can rev from idle to high speed with no hesitation and bogging. In neutral 

then set idle where you and the bike are happy. 

Many are struggling getting the Mikuni to run properly with stock jetting specs 

The Mikuni is worthless..I spent $9600 on a brand new 300 Xc-w that I have to adjust for 10 min every time I start it..Junk. They probably did it on purpose so they can start selling the TPI’s out of sheer frustration.think about it.if the Mikuni ran so great, why would I even contemplate a TPI?..now I need a $500 Lectron or $400 Keihin just to get it to run smoothly..really pissed to say the least..

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The Mikuni is worthless..I spent $9600 on a brand new 300 Xc-w that I have to adjust for 10 min every time I start it..Junk. They probably did it on purpose so they can start selling the TPI’s out of sheer frustration.think about it.if the Mikuni ran so great, why would I even contemplate a TPI?..now I need a $500 Lectron or $400 Keihin just to get it to run smoothly..really pissed to say the least..

Sounds more like your carb tuning skills are worthless... not the carb. Just saying
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2 hours ago, M A T R said:


Sounds more like your carb tuning skills are worthless... not the carb. Just saying emoji854.png

Nah, your wrong..I'm glad you love the carb and find it be no problem..You must be some kind of patient expert who enjoys riding a poorly running machine or even maybe, a magician..

Ok, so should I:

  • Stay with the constant adjusting of the stock carb (your answer I'm sure)
  • Buy a JD jetting kit
  • Buy a Keihin air Stryker 38 w/JD jetting
  • Buy a Lectron
  • or even the cheapest option: filing a V in the slide to get rid of the "gurgle" at 1/8-1/4 throttle

I wonder why all these options are recommended to owners of these junk carburetors?

Your the expert..and my skills are worthless, so please enlighten me.. :snore:

Edited by mallai
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Mallai,

Have you checked the reeds for gaps and the float height yet? That's the first required order of business.....

The float height on both my 150w and 250w were considerably off from factory and pissed all over my patio. Reeds had gaps...replaced w/VForce.  Set float height to 8.7'ish, call it a day.

The carbs aren't junk if tuned methodically from the Pilot first thru the Main and committing to one Needle Jet (I prefer the one step richer S1nj with the 5.75 slide, vs. the leaner stock R8nj and 4 slide). The stock head design is ehhhhhh, I went with RK Tek on both bikes, so my settings are going to be richer.

Highly recommend getting an Air Screw adjust knob (regardless if Keihin or Mikuni), makes life a whole lot easier...get'em at JD or RMatv.

Edited by hopsterj
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8 hours ago, hopsterj said:

Mallai,

Have you checked the reeds for gaps and the float height yet? That's the first required order of business.....

The float height on both my 150w and 250w were considerably off from factory and pissed all over my patio. Reeds had gaps...replaced w/VForce.  Set float height to 8.7'ish, call it a day.

The carbs aren't junk if tuned methodically from the Pilot first thru the Main and committing to one Needle Jet (I prefer the one step richer S1nj with the 5.75 slide, vs. the leaner stock R8nj and 4 slide). The stock head design is ehhhhhh, I went with RK Tek on both bikes, so my settings are going to be richer.

Highly recommend getting an Air Screw adjust knob (regardless if Keihin or Mikuni), makes life a whole lot easier...get'em at JD or RMatv.

+1 you did not need to buy a new carb to get the bike to run right.  I adjust mine twice a year with JD kit, 1/2 step richer on needle and 1/4 turn richer on AS for cold temps - that is it.  Starts perfect hot or cold, will lug down to a standstill and pull right out with clutch and throttle up to a nice top end.  The 17+ running issues are overblown by picky people who have zero tuning experience, the 17 is my first two stroke since 2003 and I had it running fine in less than an hour.

On the idle debate, most 2 strokes run best and are easier to tune when it is low - bike should actually die shortly after returning to idle.  Read JD's threads on jetting, they all state to run it very low for best results when tuning.

Edited by Mikek671
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8 minutes ago, Mikek671 said:

The 17+ running issues are overblown by picky people who have zero tuning experience

Bingo! and/or zero patience....haha

Stick to the proper tuning procedure/process and mark your throttle for each circuit, and one will be kindly rewarded.

Edited by hopsterj
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13 hours ago, Mikek671 said:

 The 17+ running issues are overblown by picky people who have zero tuning experience, the 17 is my first two stroke since 2003 and I had it running fine in less than an hour.

 

Just an opinion. Come ride with us when we start at 25 degrees, 8,000 feet and end at 12,000 feet and 75 degrees. (no exaggeration) You will be struggling to get over the super technical rocks when your Kuni burbles and sputters. Looking at a 1000 feet drop on a knife edge trail when  your bike is running spotty is no fun. I know some excellent tuners that threw in the towel on this POS carb. Me included. 

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13 hours ago, hopsterj said:

Bingo! and/or zero patience....haha

Stick to the proper tuning procedure/process and mark your throttle for each circuit, and one will be kindly rewarded.

or not. Seriously glad it is working for some people, but it has serious issues for many. Count yourself lucky. 

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1 hour ago, tigertiger said:

or not. Seriously glad it is working for some people, but it has serious issues for many. Count yourself lucky. 

Can understand the scenario with varying altitudes within the same riding day...that would suck.

Here in Texas it's not so bad, with the biggest change of maybe 200 to 500ft, unless riding out in West TX. Our biggest issue is Temp and Humidity fluctuation.

Will probably keep the Lectron I have for the 250 for any adventures to the mountains.

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Tiger Tiger, where do you ride in Colorado, and what carb and settings  are you using? We will be out there late this summer. the stock carb works fine for me at sea level but obviously it won't work at altitude.

 

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4 hours ago, go granny go said:

Tiger Tiger, where do you ride in Colorado, and what carb and settings  are you using? We will be out there late this summer. the stock carb works fine for me at sea level but obviously it won't work at altitude.

I'm in Montrose, and between hi country and Moab we ride from 5000 feet to 12,000, with wild temp swings! Normal day if you start early enough can be 40 degrees in the high country. 

I had a lectron on my 14 250 and loved it, never had to touch it.  Now with the RK head on my 17 300 the lectron is lacking (its a 36mm, not the HV model) so I am going to try a Keihin with JD kit. The 36mm non HV carb is going to be for sale soon.  

So.. I'm not much help but perhaps getting a JD kit for your trip here would be a good idea. If the Keihin works out I'll be selling the Lectron 
Let me know if you need I guide! I know lot of great places! 

 

 

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i 've  got the keihin and reeds, haven't used it because i haven't needed it .We wanted to do the alpine loop. i might pick up the JD kit  before we come out.

i know that it has some high mountain passes.  Thanks for the offer to guide us. I'll keep in touch.

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On 2/1/2018 at 7:24 AM, mallai said:

The Mikuni is worthless..I spent $9600 on a brand new 300 Xc-w that I have to adjust for 10 min every time I start it..Junk. They probably did it on purpose so they can start selling the TPI’s out of sheer frustration.think about it.if the Mikuni ran so great, why would I even contemplate a TPI?..now I need a $500 Lectron or $400 Keihin just to get it to run smoothly..really pissed to say the least..

The Mikuni is not that bad! I have a 17 250xc. I have the same carburetor.  I got mine to run extremely smooth at elevations from sea level to 4000'. The problem is these bikes have a very restrictive airbox that makes tuning a headache. Start by drilling as many 3/4" and 1/2 inch holes in the top of your air box as you can. Next do the carb slide mod. There are plenty of YouTube videos explaining this. The carb mod really cleans up the idle and off idle throttle response. I lowered my stock needle,  raised clip one position to position two and swapped the stock idle jet to a 35. I am running the stock main. My bike flat rips! It always starts idles and runs perfectly. 

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