YZ Wont Start


7 replies to this topic
  • yz_ripper

Posted March 20, 2011 - 05:26 PM

#1

Hey Guys, so i've got 2 days on this problem with no luck!

I put a new H/C piston in the bike, while it was apart I sent the Head to Pro Circuit for a Port/Polish. I get it all back together and the Bike started while choked, but it was idled pretty high. I took the choke off and the bike died, started back up with some throttle and she popped and crackled both while giving it gas and on deceleration. I thought the timing was off, so i checked and all is good. The only thing i can think of is the carb, and whats preventing me from checking the pilot and all other jets, is the fact i just had the carb sent to ZipTy for a good look through. Now, the bike wont fire at all. I smell gas like its flooded but no firing at all. Pro Circuit recommended i run a 160 main instead of the 162 and run VP fuel. So do you think the head isn't getting enough fuel? When i pull the carb off, the intake is wet with fuel, is it not enough or something? I don't want to bring this thing to the shop, i guess next step is to take the carb apart except this time all the jets as well. The other odd thing i noticed was the fuel screw (i use a "RIDE") when i take it out, only the spring comes down. Should the o-ring show as well? I can see it in the hole stuck up their...

Current Settings:
162 Main jet
48 Pilot
Fuel Screw 2 turns out

Pro Circuit Recommendation:
160 Main Jet
42 Pilot
Fuel Screw 2 1/2 out
Leak Jet 50

I dont want to lean this thing out and hurt the motor, i'd rather it be a little rich. What do you think? Im running a Dr. D full exhaust system as well.

Thanks for the help, again it did start but since i pulled the carb and put the 160 jet in, i get nothing now...

  • baxterj787

Posted March 20, 2011 - 05:46 PM

#2

1) Is your hotstart cable and plunger fully seated and sealing all the way? That could easily produce the symptoms you describe (lean condition). Sometimes the plunger will hang up or the plastic nut that holds the HS cable onto the carb can crack (don't ask how I found THAT out...).

2) I use a small piece of wire to fish out the small o-ring and flat washer from the fuel screw opening. Make sure you have both the washer and the o-ring and make sure the o-ring is not torn. The washer sits atop the spring, the o-ring atop the washer.

  • yz_ripper

Posted March 21, 2011 - 06:01 AM

#3

1) Is your hotstart cable and plunger fully seated and sealing all the way? That could easily produce the symptoms you describe (lean condition). Sometimes the plunger will hang up or the plastic nut that holds the HS cable onto the carb can crack (don't ask how I found THAT out...).

2) I use a small piece of wire to fish out the small o-ring and flat washer from the fuel screw opening. Make sure you have both the washer and the o-ring and make sure the o-ring is not torn. The washer sits atop the spring, the o-ring atop the washer.


The Hotstart cable huh? I'll check, right now its Hand Tightened to the carb, i think its ok when i kick it over with the Hotstart lever pulled it, its a little easier like it should be. I didnt notice any cracks but i will make sure i tight it down fully.

  • grayracer513

Posted March 21, 2011 - 06:51 AM

#4

...when i kick it over with the Hotstart lever pulled it, its a little easier like it should be.

Eh?

The hot start cable has nothing at all to do with how hard it is to kick over. It's not a compression release. All it does is to allow more air than normal into the intake.

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  • yz_ripper

Posted March 22, 2011 - 02:05 AM

#5

Eh?

The hot start cable has nothing at all to do with how hard it is to kick over. It's not a compression release. All it does is to allow more air than normal into the intake.


I need some help trying to figure this out, do you know? if yes then post something that pertains to the original question.

Thanks

  • dgcars

Posted March 22, 2011 - 03:53 AM

#6

Eh?

The hot start cable has nothing at all to do with how hard it is to kick over. It's not a compression release. All it does is to allow more air than normal into the intake.


I need some help trying to figure this out, do you know? if yes then post something that pertains to the original question.

Thanks


I think Gray was just trying to point out that pulling the hotstart did not reduce compression and so avoid further confusion. Once you understand the function of the levers/controls, solving the initial problem gets easier.
I would check for a clogged PJ in the meantime. :thumbsup:
Generally, if you run VP, then the norm is to up on jet sizes.

  • yz_ripper

Posted March 23, 2011 - 02:44 AM

#7

I think Gray was just trying to point out that pulling the hotstart did not reduce compression and so avoid further confusion. Once you understand the function of the levers/controls, solving the initial problem gets easier.
I would check for a clogged PJ in the meantime. :thumbsup:
Generally, if you run VP, then the norm is to up on jet sizes.


Yep, so as it stands now I have the carb apart and blew out all the jets, etc. I'm going to wait Until the new set of jets come in (a little bigger) and then I'll test it out. When I pulled off the carb after kicking it over a few times, the intake part of the head had no fuel and wasn't wet at all, the spark plug was dry and didn't smell like gas either. Got to be a carb thing.

  • yz_ripper

Posted March 24, 2011 - 07:12 PM

#8

Alright so i got my new jets, installed them and watched the gas squirt directly into the intake as i looked from behind the carb, so why wont the bike fire? Im telling you timing is dead on, piston at the top, etc. I even shot a bit of either into the intake... No fire!
***!

Thanks





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