250 The 1999 YZ250

[Trfsrfr]

you say it wont rev: OK, is it sputtering and trying to catch,

Yes, sputtering.

run your tests with the choke knob screwed down snug, not just pushed down, and NO, it won't idle.

It wont idle because they dont, and I should forget about trying? Or because I got other things keeping it from idling?

what does your manual show?

I am not sure yet. I am not even sure it's the right manual, and I have downloaded at least 6 or 7 different ones, but the one that I have that I believe is closest, is for a 1998 YZ250 L (LC) - my bike is a 1999 L1.
Plus it's 550+ pages long, and in 4 different languages, and not arranged very well in my opinion. My Kawasaki manual is much better. It takes a long time to page through all of the other languages to find what I am looking for and read it in a cohesive manner.
I am trying to find a pdf manipulation program to delete all of the extra foreign language pages so I can condense it, but haven't had any luck so far with one that will work with my Linux OS, and I've tried 3 now,

does that mean you have it turned all the way in, snug against it's seat?

Yes, that is a setting that I found in a chart online for these temps and altitude.

I just got out into the garage after a long day and will try to recheck the float setting. It ran better before I touched it last so I am thinking I should change it back...

 

[ossagp]

Your not reading me here: I said screw the choke knob down for your TESTS. That takes the screwed up enrichment idle circuit out of the quotient and that leaking bleeding piece of shit is sometimes the entire reason for blubbering and plug fouling.

You never really explained what the suggested method is the manual is for setting the float. Please do so now.

I have been around these critters a very long time and have NEVER seen a fuel or air screw setting of "0" printed in anything. Set it out at 1.5 and whoever/whereever you got that should be avoided or reread it until is says something else.

You might save your time and and get any better at taking the float bowl off if you will tell me your procedure and if possible provide a reprint of the one given in the manual.

 

[Mihylo33]

Your not reading me here: I said screw the choke knob down for your TESTS. That takes the screwed up enrichment idle circuit out of the quotient and that leaking bleeding piece of shit is sometimes the entire reason for blubbering and plug fouling.

You never really explained what the suggested method is the manual is for setting the float. Please do so now.

I have been around these critters a very long time and have NEVER seen a fuel or air screw setting of "0" printed in anything. Set it out at 1.5 and whoever/whereever you got that should be avoided or reread it until is says something else.

You might save your time and and get any better at taking the float bowl off if you will tell me your procedure and if possible provide a reprint of the one given in the manual.

Ah, yeah sometimes you get the manuals and some of their explanations are jumbled through translation.

 

[2Wheels]

Your're reading the moto autkschlung!

Seriously though, I've never set my float with a mic to any success. Saying the "measurement" is right therefore it must be right is subjective. +-1mm eyeballed with a mic parallel with the bowl surface while holding at a 45° and "first contact with the float tang" is an imperfect system.
Like I said before, go too far then not far enough and note the difference between and find somewhere in the middle. Find the point were it runs best, and then look elsewhere if it still runs poorly. I Like to use carb cleaner and a .010 string and magnifying glass for the jets.

 

[ossagp]

mikuni had the best system for setting in that dual float and yoke setup. Yamaha typically calks for using a sight tube. easy to make and leave in place. but you can have the bowl on and off several times.

 

[Trfsrfr]

I didn't do anything to the bike last night, was too tired.
But I did take it and the kid to the track today.
I screwed the air screw out 1-1/2 turns, and I cant find the chart that I used that said to set the air screw at 0 turns.
It always starts on the 2nd or 3rd kick. When warm the idle "hunts" a bit.
It seems to sputter from about 1/8 to just over 1/4 throttle, but when it hits it goes good.
Did a plug chop and the plug looked the same as last time.

The method I used to set the float is the 45 degree angle method, measured from the float bowl surface with a mm rule I have, with the tang touching but not pressing the plunger.

Below is a screenshot of the 1998 manual I have that specifies how the factory recommends it be set;

 

[Trfsrfr]

After reviewing some footage of our day today at the MX park, I am wondering what y'all think about it, and the tuning process I am looking at.
In my helmet, when the bike hit it's powerband, it sounded and felt good; but now after watching the Gopro vid I am unsure.

The link below is a rookie 4+ minute lap around the "National" track (keep in mind I dont have an hour of ride time on this bike, and less than that on this track), and the bike sounds differently than it did in my helmet.
Also, the front tire needs replaced, and add that with my age, and lack of MX track experience, I am riding at a very low (cautious) level.
My main objective is to arrive functional at work on Monday, and dial the bike in like we have been discussing...
https://youtu.be/S2ExFOJIx44

 

[ossagp]

After reviewing some footage of our day today at the MX park, I am wondering what y'all think about it, and the tuning process I am looking at.
In my helmet, when the bike hit it's powerband, it sounded and felt good; but now after watching the Gopro vid I am unsure.

The link below is a rookie 4+ minute lap around the "National" track (keep in mind I dont have an hour of ride time on this bike, and less than that on this track), and the bike sounds differently than it did in my helmet.
Also, the front tire needs replaced, and add that with my age, and lack of MX track experience, I am riding at a very low (cautious) level.
My main objective is to arrive functional at work on Monday, and dial the bike in like we have been discussing...
https://youtu.be/S2ExFOJIx44

Did changing the airscrew setting change anything.

 

[Trfsrfr]

Did changing the airscrew setting change anything.

It maybe allowed it to idle, but it hunts up and down now. Not a steady idle.

 

[2Wheels]

Ok so I understand "hunts" you mean if you pull in the clutch in gear while riding it struggles and sounds as if it's going to die, and then with a blip of throttle and it idles up and stays?
What did you use to clean your jets with? Make sure they are nice and clear, including all circuit passageways.

 

[Trfsrfr]

Ok so I understand "hunts" you mean if you pull in the clutch in gear while riding it struggles and sounds as if it's going to die, and then with a blip of throttle and it idles up and stays?
What did you use to clean your jets with? Make sure they are nice and clear, including all circuit passageways.

No, what I mean by hunts is that it idles up then down, then up, then down, and so on...
It is hunting, or searching, for a place to idle.
I cleaned my jets with carb cleaner, compressed air, and a magnifying glass. They're clean, with nice round holes.

 

[ossagp]

so you didn't like the idea of screwing the enrichenor down tight?

 

[Trfsrfr]

so you didn't like the idea of screwing the enrichenor down tight?

@Andy, I have no problem taking the advice of 9.5 out of 10 people on this site, you guys are awesome.

But you need to understand that sometimes I am too smart for my own good, my own worst enemy some days, and often times a complete and total moron, like right now.
I've been out in the garage messing with this thing for last few hours and been scratching my head...
So I went back to square one and lo and behold, I find my dumbass relearning the basics.
It turns out that this engine (and I assume others) actually needs gas to run!
Who'da thunk!?

I still need to dial it in more, but I took it for a rip around the block and she accelerates nicely, doesn't sputter, and generally runs closer to like it should.
In my haste while first getting it going I only put in a small amount of fuel because I didn't know how long it would take to get it running and I didn't want to have a bunch of gas go bad, or be lifting a heavy tank on and off again a million times.
Dipshit I am.

 

[2Wheels]

At least this was anonymous dipshittery. I was at the track once repeatedly kicking my bike only to realize I left in the wash plug.

 

[Trfsrfr]

I started wondering if maybe the gas cap vent hole was somehow plugged, so I took it off to blow through it and thought hey, lets check the fuel level...