125-200cc 09 Wr 125 Bog/Performance Solved?

Dwight also check it with the 175 main. That sharp point really allows the fuel to flow at 1/2 to wo throttle positions.

Yes Sir, Mr. Bean !

I am running 175 main and 35 pilot in the 36 pwk. Can't remember what clip, but I am thinking #2
GP

Picked up and extra 175 main, 172 main and a 168 main today. The 36mm PWK has a 170main in it stock. I am trying to find somewhere to do some testing next weekend. I hope to have the 36mm then. I want to get the 38mm as good as I can then go test the 36mm. The 36mm should have a NOZI needle in it stock.

1. 1. OK, I did some more testing with the 38mm PWK A/S. Clear day, 55F degrees, 300ft. ASL. Got it working best that it ever has with the KTM NOZF Needle. No bog. Sometimes I can still get that over carburated feeling , (just a bit of hesitation if you open throttle too fast at lower RPM), but overall pretty damn good. Jetting : #7 slide. NOZF Needle in the #2 position. A/S 1.5 turns out. Pilot #40. Main Jet 175. The needle is a LOT richer than the JD Blue.
      Then, I put on the 2011 KTM 150XC Keihin 36mm PWK A/S. Almost an immediate improvement feeling. I rode it hard for about 10-15 minutes in the sand pit. Then a slight bog came back. I went back to truck and pulled plug. Showing a much lighter color. I also noticed that the carb was spewing every now and then a bit of fuel from the vent tubes. I decided to raise the NOZI needle from the stock #3 Position to the slightly richer #4 Postion. I also slightly lowered the float level. Immediate improvement. I rode hard for about 10 minutes and was loving it. No noticeable loss in top end power and improvement in the low mid-range area. I decided to play with the Air Screw. Stock setting was 1 3/4 turns out. #42 Pilot Jet. I started turning the screw out and it wouldn't idle up till I got to 4 turns out. Too Rich. I pulled the 40 PJ from my 38mm and put it into the 36mm. Another improvement overall. BUT, my Air Screw is still about 3 turns out. I picked up a #38 and a #35 PJ on the way home from the KTM shop. I plan on installing the #38 PJ. I figure my Air Screw will end up close to 2 turns out. Both setups are pretty close with the nod going to the 36mm PWK A/S.
   1. I had to use the Cable L at the top from the Mikuni TMXX on both Keihin carbs. It fit. The 38mm PWK has a screw top and the 36mm PWK has 2 allen screws (3mm wrench size).
   1. Final Jetting on the 36mm PWK A/S : #7 slide (Stock). NOZI needle, Clip #4 (Stock is NOZI needle, Clip #3). Air Screw 2 turns out (Stock is 1 3/4). #38PJ (stock is #42). Main Jet #170 (Stock).
   1. Can't wait to try it out at the Nat'l Enduro in a couple weeks.

If you get a chance, try the the NOZF in the 36 PWK. Check the slide in the 36, mine is a 6.5.
I will pick up one of those NOZI needles to try next time I am at the KTM shop.
GP

Slide was a 7.0 . I checked. The NOZI is working great in the #4 position. It is a bit leaner needle than the NOZF. The smaller carb will need a leaner needle. The NOZF is already in the #2 position on the 38mm so I would run out of adjustment very quickly. A NOZH or NOZG might work.

I am having good luck with the NOZF, but mine is still a 125, so there may be differences on a 150. I will try some more needles though.
GP

Yes, The 125 will not draw as hard on the carb as the 144. So it will need a bit richer setting for sure.

Year & Bike Model = 2011 WR150

Carb = 36mm Keihin PWK A/S from 2011 KTM 150XC

Pipe & Silencer = Stock pipe / FMF S/A silencer

Other engine mods = Exhaust spirngs Stock / silver.

Premix ratio & fuel type = Maxima Super M 40:1 or K2 , 100LL AvGas / 110 Sunoco race gas mixed 4 gal AvGas to1 gal Race Gas. Non Ethanol Gas is no longer available in Mississippi and may not be anywhere according to the Gas Distributor.

Temperature range (deg F) = 50F - 70F

Elevation (feet) = 300ft. ASL

Main jet = 170 (stock) (tried a 172 and got a bit of a slight blubber at 3/4+ throttle till at RPM)

Pilot jet = 35 (stock #42)

Needle = NOZI (stock)

Clip position = stock #3

Air screw setting = 3 (stock 1 3/4)

Slide = I am going to a 6.0 (stock 7.0) Reason for changes is that there is now a flat spot at the 1/4 throttle position. I am extremely close.

Testing went well. Good throttle reponse and no blubbering. We will see next weekend at H/S.

Got 4th at the H/S. Lots of LONG straights and soft uphills put me at a disadvantage to big bores. They would catch me on the uphills at times and then pass me down a long straight at 10mph faster. Bike ran well. Just a slight hesitation at the 1/4 throttle mark that makes me wonder whether it is the big carb or do I need to drop the needle back to the #3 position since going to the #6 throttle slide. I also have a 35 pilot in but still seems to be pretty rich down low as it starts with no choke or minimal choke in 45 degree weather. I am also getting some spooge at pipe end and connection.
I pulled the plug after the event and it was a dark grey color with some soot on it. The grey probably is coming from the leaded fuel but it wasn't a light grey. I may try the needle in the # 3 position at the Nat'l Enduro as so far I am only getting 14.3 mpg. I would like to get over 16 mpg. I can't trust it over 40 miles on a tank right now. AND I have the 2.8 gallon tank. I am also switching from Maxima Super M to Maxima K2 as I have been told that it is better oil. Cleaner, better protection and develops more power.

OK, I have readjusted my float level AGAIN. I have changed to Maxima K2. I ran the bike this weekend at the Cajun Classic Nat'l Enduro. I got 5th after a weak showing in the first section but the rest of the day went pretty good. I was also running a bit too large tire on the back. Worked OK everywere except the sand washes and loose ground where is bogged the bike some and wouldn't allow it to pull up on the pipe quickly.
I am still running the Keihin PWK 36mm Air Striker from the 2011 KTM 150XC. I am running the 170 main jet (Stock), 6.0 slide / throttle valve ( stock is 7.0), NOZI needle in the #3 position (Stock), and a 35 pilot jet. I had to adjust the Air Screw out to 3 turns. (35 is smallest available pilot jet)
Carburetion was very very good. Bike ran better than ever. Little to NO spooge at pipe connection. My milage has now gone from 14.3 mpg to over 18 mpg. At first gas stop I figured I was getting about 20 mpg. Next two gas stops I was getting a bit over 18 mpg.

Everyone tells me there is no 32 pilot. Smallest is a 35. I have a 6.0 slide in it right now. I don't want to hurt the 1/4 to 1/2 throttle range because it is working pretty good. I would like to lean out the 0-1/4 range a bit. Should I be looking at a 6.5 Throttle slide ?

I am running a 6.5 on my 125
GP

I checked the Sudco catalog and 35 is the smallest they show.

Dwight,

You might take your 6.0 and 7.0 slides to a good machinist and he can cut your 6 slide to 6.5 if you want to try that. Just a possibility.

I hate to do that as I don't have another 6.0 incase the 6.5 doesn't work. I have been looking on Ebay as recommended. Call me tomorrow, I want to discuss the mods to the 167 and the PVs. I am wondering which I want to do as I have a couple weekends coming up after this weekend's H/S. Next race.............NATRA / TN Nat'l Enduro ( Rad Dad ).

I have installed a NOZH needle as someone pointed out that the NOZ_ series needles are short and I may be drawing extra fuel from the Needle and Main jet. So instead of a NOZI in the #3 position, I have a NOZH in the #2 position.
I have also installed WallyBean modified Power Valves for the Nat'l Enduro next weekend. Should help the transition bog some. I have most of it out but it still crops up sometimes. I am also going to install the 167cc top end after this weekend so I can break it in before the next race. I plan on working on the La. Trail Rider enduro, Easter weekend. Should break in the new top end nicely.

I'm sorry that you chose to remove your post. My bike has never run stronger. I still haven't put the small silver spring back in, but I will soon. Putting the power valve back in time was what it needed. I rode for three hours yesterday and I was delighted with how strong it is. Your combination certainly works for me.