Quick Needle Changes?

5 replies to this topic
  • Patman

Posted October 03, 2000 - 06:10 PM


Ok guys, a few things to start. One, I'm new to this forum, and I'd like to say that I've learned more about my bike here in the last two hours than in the last two months of ownership. Two, like any NEW member should, I've scanned through ALL of the posts to make sure my question hasn't been answered before, & I don't think it has been.
So, here goes. We've all decided that it's a given that you gotta change the needle clip position at one time or another...me, I gotta go a notch richer, today...for this weekends race. But next week I'm off to Red Mountian Calif. & will probably have to do it all over again. My question is this, is there a fast method, trick, shortcut, or work around, to do a five minute clip change on this carb? Is there a quicker than average method? Is there a way to do it twice in the same month? Or year...and still have time to ride.

Thanks in advance.
Patman the Impatient

  • James_Dean

Posted October 03, 2000 - 09:04 PM


'00WR and YZ models don't have a hot start hose so:
1)disconnect the throttle cable at the grip - 2 screws
2)pull the carb clamps screws out - 2 screws
3)disconnect the TPS plug
4)disconnect the fuel hose at the carb (turn off gas :) )
5)carefully pull the carb out the left side turning it at 45 degrees while sliding the throttle cables down from the top only far enough to access the top of the carb. The drain hoses come with it. A little fuel may come out the drain hoses.

Work on the carb with it held up by the throttle cables. There is enough friction there on the cables to hold it in place while you work.

Put it back in while pulling up on the throttle cables from above. Reinstall the clamps, throttle, fuel line, and TPS.

James Dean

  • techman

Posted October 09, 2000 - 01:42 PM


I actually changed my needle clip and main jet without removing my carb (00 YZ426). I just rotated it enough to get at the main jet from underneath, just knowing which jet to unscrew via approximate location and by seeing that the right type of jet came out on the end of my socket. Then I rotated the other way, undid the top cap, and was able to undo the fasteners and lift the needle up to access the clip. I used the throttle to hold the assembly up near the top of its slide when I did the needle. The only real "dirt entry" problem was when the top cap was off, as opposed to undoing the air boot with its associated high chance of dirt falling into the carb. I didn't undo any wires, throttle cables or anything but was careful not to yank too hard on anything during the carb rotating. Hope that helps.

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  • James_Dean

Posted October 09, 2000 - 02:52 PM



Did you do the needle with the tank on?? Seems like a tight squeeze under the tank.

Last time I took the carb needle out was in just under 5 minutes leaving the tank on but pulling the carb out to the side. Putting it back together took longer.

Main jets are a little tricky leaving it on and tipping the carb. Takes a delicate hand and a 6mm socket.

[This message has been edited by James Dean (edited 10-09-2000).]

  • techman

Posted October 10, 2000 - 04:24 PM


Hi James,
It was a tight squeeze and I got someone to hold the throttle for me while I played with getting the needle unfastened, reclipped and back in. It was somewhat an exercise in being careful and using patience, but had no major snags.

I get real delicate and concerned whenever I mess with a carb because it takes so little to screw them up and if they get dirty and stick open !!!, or, alternately I hate kicking a bike over a zillion times and having it still not start. The idea of just pulling the main jet out the bottom comes from many years of playing with 2 stroke mx bikes where you just tilt the carb for top/needle and bottom/main work.

  • Patman

Posted October 15, 2000 - 05:40 PM


Thanks for the info guys. I was able to do the job as needed to deal with a cold front that hit one day befor a cross country event...( this thing's really not a very good tight woods bike ) I used a wrench to pull the plug from the bottom of the bowl, then a mirror to get an idea of where I was going, I used the usual 'jet wrench' to pull the main, & a 90 deg. flat blade scrwedriver for the pilot. ( made from the flat blade tip out of my ratcheting screwdriver ) then I used the method described above to turn the carb slightly, pull the top, use the throttle to pull up the slide, & bam! done in 30 minutes. All three jets.
Thanks again folks.

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