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TX300 Carb setup, PWK vs Mikuni

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I saw one member mentioned purchasing a pwk from JD jetting, has anyone else gone that route as well? how do you like it compared to stock? I have one with his needles setup with a new metering rod from one of our honda forum members that was initialy going to be for the honda, but if it would really wake up this tx that would be awesome! for the first couple hours im just running stock factory everything till she breaks in a little, but will be switching soon to a a 50:1, or 60:1 mix with e free/100llav fuel for the sake of motor longevity. the PWK was a real difference on 02, and that new metering rod only makes the intake much more efficient.

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It seems like the mikuni's settings from Ktm are very rich.  I'm riding from 1500' - 5000', using the jetting for 7500' - 10000'. but with a 37.5 pj, 430 mj. runs good.

edit: I also did the slide mod - 7.9mm x 1.9 mm. Had to turn the idle down right to the point where the idle screw loses contact with the slide. Then adjusted the air screw out to just crisp when wacking open the throttle. Feels good. Ill ride it over the weekend to get a better idea of how it runs...

Edited by absurd

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I ordered a set of needles from JD the other day, can never have too much brass to tinker with! although i'm still looking for answers on premix ratios with the new engine and AV fuel

 

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I personally don't think there is going to be a vast difference if both carbs are well set up. My personal opinion is that it isn't worth wasting money on a new carb, but I am cheap and would rather fix something I have than replace it. That said if the pwk is a beast yout are more comfortable tuning, go for it. 

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I feel like I have my mikuni set up very well. However I have the opportunity to try out a 36 PWK Keihin that I can't pass up, so I will install it and see how it goes... I have heard good things. 

Also, on the trail yesterday, a guy in a '16 300 with a keihin idled by and then took off... it sounded perfect, it lit a fire to try out the Keihin.

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10 hours ago, rlucas1986 said:

I feel like I have my mikuni set up very well. However I have the opportunity to try out a 36 PWK Keihin that I can't pass up, so I will install it and see how it goes... I have heard good things. 

Also, on the trail yesterday, a guy in a '16 300 with a keihin idled by and then took off... it sounded perfect, it lit a fire to try out the Keihin.

If You Have a Kehin available it's worth trying. 

 

Personally I didn't really struggle getting my tmx working great. I only had to drop the needle a clip after my initial setup. 

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Went to install the 36PWK and the throttle cable was too short. At this point it's not worth messing with the stock cable or getting a whole new assembly/cable just to play around with it. Back to the Mikuni for me.

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3 hours ago, rlucas1986 said:

Went to install the 36PWK and the throttle cable was too short. At this point it's not worth messing with the stock cable or getting a whole new assembly/cable just to play around with it. Back to the Mikuni for me.

You need a 16 throttle housing and cable for either a Lectron or Kehin.

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6 hours ago, Bryce418 said:

You need a 16 throttle housing and cable for either a Lectron or Kehin.

17 TC250: I tried a 38 mm Keihin PWK AG (top cover held by two screws) and used the stock cable/throttle housing. Had to adjust the fee play on the throttle close to minimum but no issue.

Now using a 38 Keihin PWK AS (plastic top cover is screwed on) and still no problem with stock cable/throttle. Actually tons of free play adjustment left 

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17 TC250: I tried a 38 mm Keihin PWK AG (top cover held by two screws) and used the stock cable/throttle housing. Had to adjust the fee play on the throttle close to minimum but no issue.
Now using a 38 Keihin PWK AS (plastic top cover is screwed on) and still no problem with stock cable/throttle. Actually tons of free play adjustment left 

Why the 2 different carbs? The AS is the long body and also a bit wider front to back, correct? What has been the performance differences?

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2 hours ago, KennyMc said:


Why the 2 different carbs? The AS is the long body and also a bit wider front to back, correct? What has been the performance differences?

The AS is longer , correct.

The AG was not fitting well at all in the intake rubber boot and i was not sold on the way it ran.

the AS needs the XC-W shorter flange and it's harder to install but it's been running great. Really cleaned up the low/mid range.

I thought I finally got the TMX dialed in but temps have increased a lot here in FL and it's again almost impossible to compensate only with AS adjustment.

These 17 are nuts anyway. Got a buddy on a 250 SX and his TMX jetting specs would not work at all on my TC. we swapped bikes and could not believe the difference.

 

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On 4/18/2017 at 8:03 PM, mxstate said:

The AS is longer , correct.

The AG was not fitting well at all in the intake rubber boot and i was not sold on the way it ran.

the AS needs the XC-W shorter flange and it's harder to install but it's been running great. Really cleaned up the low/mid range.

I thought I finally got the TMX dialed in but temps have increased a lot here in FL and it's again almost impossible to compensate only with AS adjustment.

These 17 are nuts anyway. Got a buddy on a 250 SX and his TMX jetting specs would not work at all on my TC. we swapped bikes and could not believe the difference.

 

The SX and TC both come VERY rich, 42.5 pilots which is MUCH richer then the XC/XCW/TE/TX's which came with 32.5 pilots. One of yours might have a reed issue because my buddy and I both have 17's, SX & TC, with the same mods and jetting, and they run very similar, the TCs air box is slightly modded for more air..

What is your jetting? From the sounds of it you still have rich pilots in they came with? drop down to a 30 or 32.5 if you do. 

Edited by TommyB 754

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SO i borrowed a buddies Keihin 36 PWK, cable and throttle. The recommended JD Jet kit is installed but it is for a pre-'17. Starts so well and Idles well too.. but it is definitely not as strong as my Mikuni... but this was just the first try! I have hope! It seems a bit lean. I will be testing it this weekend.

 

In the mean time does anyone have 2017 300 Keihin recommendations that realllly work well?

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SO i borrowed a buddies Keihin 36 PWK, cable and throttle. The recommended JD Jet kit is installed but it is for a pre-'17. Starts so well and Idles well too.. but it is definitely not as strong as my Mikuni... but this was just the first try! I have hope! It seems a bit lean. I will be testing it this weekend.
 
In the mean time does anyone have 2017 300 Keihin recommendations that realllly work well?

There are a few threads on KTMTALK on this subject. One guy has a TE300:
N3CK needle (Yammi) 4th clip
178 main
42 pilot
1 1/2 turns out on A/S

I had a '15 300XC-W and I ran:
NECH needle (Suzuki) 3rd clip
168 main
38 pilot
1 1/2 turns on the AS


There is a guy running the JD stuff and he just went one step richer on the main jet then what was recommended and he said it was perfect.

http://ktmtalk.com/showthread.php?533148-Keihin-carb-on-2017-300XC
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Thanks for the responses! i havent heard of ktmtalk so will start delving over there for info as well. I got a chance to test my new jd kit today at the local dnr trails with the mikuni.
420 main 30 pilot blue needle 2.5 from top clip and was about 1 1/2 to 2 turns out on the as for a really nice 60 degree. bike felt good almost everywhere but noticed if I chopped the throttle and let it wind down but tried to wick it quick it would still bog out. another strange issue, my bike died going down a trail and wouldnt start. I had fuel draining pretty easily when the bike was leaned and had even re routed the overflow per the directions in the jetting kit. i unwound the overflow and turned my gas to reserve and for whatever reason it would run again and i was lucky to get back to the truck quickly vs pushing all day. i have not checked my float level, will look at some youtube today and get an idea on that as well.
 

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1 hour ago, Ronaldo156 said:

Thanks for the responses! i havent heard of ktmtalk so will start delving over there for info as well. I got a chance to test my new jd kit today at the local dnr trails with the mikuni.
420 main 30 pilot blue needle 2.5 from top clip and was about 1 1/2 to 2 turns out on the as for a really nice 60 degree. bike felt good almost everywhere but noticed if I chopped the throttle and let it wind down but tried to wick it quick it would still bog out. another strange issue, my bike died going down a trail and wouldnt start. I had fuel draining pretty easily when the bike was leaned and had even re routed the overflow per the directions in the jetting kit. i unwound the overflow and turned my gas to reserve and for whatever reason it would run again and i was lucky to get back to the truck quickly vs pushing all day. i have not checked my float level, will look at some youtube today and get an idea on that as well.
 

You can have 2 issues going on. 

1 - float bowl is too high so when the bike is leaned over it flows out

2 - some small piece of debris is keeping the float pin from seating all the way

Float height should be ~8.7MM, which is about where the weld line on the plastic floats is parallel with the carb base.

 

Picture does not represent what the Mikuni floats look like, just an example of how to measure the float height.

 

CARB.jpg

Edited by KennyMc
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thanks for that! I think i found the culprit. noticed that it was the tank being low and needing to be on reserve. once the level is just below not being able to see on the right side mine will need to be turned to reserve. wonder if it's a reminder thing like "hey you only have this little bit on the left side left" when you have to switch.

anyways, yea, dropped the blue needle another clip to 3.5 with the air screw out at 1.5 and it was running good! that bog on the wick went away so i got myselve into the ballpark. I ran outa gas and started using my 40:1 LL fuel and could tell that it was a little more blubbery in the slow stuff but still crisped up when you got on it. might need to order even smaller pilot but for now going to enjoy it before the weather changes and im chasing something else!

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