125-200cc WR125 tuning question

[Scootskipper]

Ride report from hell

Yes David it's better to talk about things...so lets hear it.

It had rained the night before and it was pretty greasy. I actually started out doing really well. I had a slow start, but started catching people in the woods quickly. Apparently most of the young bucks were just being too aggressive in the slick conditions. I was just cruising along having a blast but about a third of the way in to an eight mile lap, my tires got packed and from there on it was an epic struggle just to get anywhere. I fell at least three times each on several hills. Anywhere that it was the least bit off camber, I was on the floor! I wasn't the only one having trouble. There were crashes everywhere. At one point, I was attempting to recover from having fallen back down the same hill about three times, some guy came along with his bike on fire! People were running towards him at first, but someone yelled that it was going to blow up and they quickly turned around and ran the other way! I ended up helping the poor fellow as best I could. We dipped our helmets in a nearby creek and tossed the water on the bike until it was out. At that point I realized that it was two and a half hours in to a two hour race and since I was at a paved road that led back to the start I decided that I had had about as much fun as I could stand and headed for the barn. I got back to scoring and the scoring people were gone. There were moms and wives milling about upset because there were guys still in the woods racing. It reminded me of those stories of Japanese WWII survivors that were holed up on islands and didn't know that the war was over.

 

[john01]

WOW!!! You should have just came to the club, kids day was a BLAST. LOL I wonder if all the guys made it out. Was the fire bike a KTM?

 

[rockdancer]

First Off, the PWK has a 45 Pilot in it. I went 42 then 40. It was getting too much fuel when you rolled the throttle. I was going to even try a 38 or lower but pulled my back out. I went with the 185 main and I think that I am going to push to see if a 190 will work. My bike likes fuel on top and lean on bottom.

Water racer where did you get your NOZF needle at?

Thanx!

I agree with this too -

 

[Scootskipper]

WOW!!! You should have just came to the club, kids day was a BLAST. LOL I wonder if all the guys made it out. Was the fire bike a KTM?

Kid's day is probably where I belong. Would they let me ride? No the fire bike looked like a Yamaha. It was a four stroke, I think a 250 but not sure. I don't recall the name of the guy who was at the club Saturday with his family, but he was there and the fire bike was loaded up with him after the race. I assume that they came together.

 

[water racer]

First Off, the PWK has a 45 Pilot in it. I went 42 then 40. It was getting too much fuel when you rolled the throttle. I was going to even try a 38 or lower but pulled my back out. I went with the 185 main and I think that I am going to push to see if a 190 will work. My bike likes fuel on top and lean on bottom.

Water racer where did you get your NOZF needle at?

Thanx!

Believe it or not, it was the spare needle that came with my KTM 250! The KTM has a NOZE in it and the F is a little richer.
My first attempt with the PWK I went big pilot and little main and JD blue, wouldn't work, then I saw your settings, and it was better, but would still die when whacking open the throttle. I will repeat that it would pull up to half throttle, but more than that it would die. And when I say die, I mean it quits running. New meaning to the word bog. same thing I had been fighting with the mikuni. That is when I realized it needed more fuel mid to top, went with the NOZF because it measured thinner. Someone that knows Keihin needles may find something better, that is just what I had to try. I even tried the 6.5 slide out of the KTM, but did not seem to make much difference as far as solving the problem.
I am thinking like you, I would now like to try a smaller pilot and a bigger main. I realize this is contrary to what some others have found, but this is where I am at for now.
I had my mikuni working pretty well, but the pwk will just about idle up a pretty good hill.
GP

 

[john01]

I think David's problem is in the pilot being to big also. I think we will or should start with that. The bike will just not go at ALL when you wack the throttle from a slow 1-2 gear roll. It's like someone hits the kill switch.

 

[water racer]

that sounds like mine. If the pilot was to big, it would go, but blubber. I think he is running out of fuel mid range, but it is easy enough to change.
GP

 

[dartyppyt]

I jumped on mine last night and since the summer heat/ humidity is on I figured that it changed a bit. I had a slight hesitation rolling the throttle on. I backed the air screw out to about 5-6 turns until it went away. I will try a 42 pilot and I still want to try a 190 main. These things like being fed on top.

 

[Scootskipper]

I want to thank everyone for the responses. I picked up a selection pilot jets yesterday and I look forward to testing tomorrow.

 

[water racer]

I jumped on mine last night and since the summer heat/ humidity is on I figured that it changed a bit. I had a slight hesitation rolling the throttle on. I backed the air screw out to about 5-6 turns until it went away. I will try a 42 pilot and I still want to try a 190 main. These things like being fed on top.

Turning the screw out leans it, so you may want to think of your origional idea of smaller pilot.
GP

 

[Norman Foley]

I want to thank everyone for the responses. I picked up a selection pilot jets yesterday and I look forward to testing tomorrow.

Give us a report! I'm on hold with PWK carb tuning, until I install the Factory 144 kit.

 

[Motosportz]

Give us a report! I'm on hold with PWK carb tuning, until I install the Factory 144 kit.

I should be able to shed some light on the 144/PWK tuning after this weekend.

 

[biggs]

Hey David, Where did you find the jets Locally. I want to get some for my GG 200 .

 

[Motosportz]

Hey David, Where did you find the jets Locally. I want to get some for my GG 200 .

any shop should have them.

 

[Scootskipper]

Ken's Cycle. I'm sure that you've heard of him!

 

[john01]

Hey David sorry I missed your call today and make it to the club. My son, his son, my wife, and I went to trade in my 09 TXC 510 on a 09 WR250. Well that was the plan anyway. It seams the price on the Wr250 jumped $700.00 and an added $500.00 freight was also added. So needless to say I still have my TXC and I hope the WR stays their a long time. They did offer me $200.00 more on the trade as they had quoted. Anyway, how was it at the club today and did you get any tuning done? BTW we are going to the club tomorrow.

 

[Scootskipper]

Can someone tell me the difference between the "blue needle" and the "red needle"?

 

[water racer]

I am not an expert, but basicly, the blue is thinner and lets more fuel through, so it runs richer than the red. The idea is that you may need to switch to the red for hot weather or higher elevation.
Niether one was rich enough for my bike to pull from low speed to wide open, so I am using the NOZF which is thinner yet making it richer. There is a whole lot more to it than just diameter, they all have different tapers as well. I still don't have the perfect setting, but it is very ridable.
GP

 

[Philbilly]

Got my carb from Kelly a couple months ago and it had a 45 pilot in it. Mine had a bog (sometimes) that I "think" I finally tuned out. I'm running a 165 main, red needle 3rd pos, and a 42 pilot, AS 2 turns out. I haven't trail tested it yet, just running it up in down the gravel road here. I'm running lean cause I do mostly trail riding in the lower rpm ranges. Elevation: 700 ft, 80 degrees, 93 octane w/ Amsoil at 40:1. Will let ya know how it does on the trails after this weekend.

After 3 days of riding, temps 80-85 with some humidity @ 700ft elevation I did some experimenting. My '09WR125 has always ran pretty good on the bottom (lugging) and good on top but I've been trying to get rid of the bog (lack of torque) during the transition from bottom to top...I lowered the needle in steps, I'm now at pos 1 and the AS 2 1/4 out. It's running crisper on the bottom and it seems to run cleaner now into the top but still has that lack of torque so the only thing I have not tried is lowering the PV arm a smidgin as Kelly suggested. Maybe go leaner on the pilot as it just takes a few seconds to run well without the choke when the engine is cold? Any other suggestions, please help!

 

[Scootskipper]

I had gone to the 165 main and it felt okay just running back and forth in my yard and whacking it. Sunday I ran a hare scramble that the course opened on to some straight, fast fire roads for stretches and it just stuttered and died when I went to really wring on it. I just short shifted and never really opened the throttle all the way. I'm just going to have to start over on this tuning business.