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Discussion Starter #1
Did the YZ CAM timing Mod.
Air box removed
Baffle out of the pipe

170 main
5th clip on the needle
148 pilot

Bike starts very easily
no hesitation off idle
Plug reads light brown

The problem is that through the first 1/3 of throttle play the bike sounds like the rev limiter is on. It pops and skips and the power is a bit flat. Once you get past that first third the sound cleans up and the bike really gets a power hit.

I thought I read on another forum that if, when jetting, you twist the carb and over tighten the throttle cable you can stress some micro switch or something putting it out of adjustment.

Anyone know anything about that and if this could be the cause of my problem?

I was pretty careful to not put too much pressure on the cable, but it's a tight fit getting access to the needle and some stress may have been placed there.

Any help is greatly appreciated.

Thanks
 

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LT,
It sounds like you are a little rich. I am running a 45 pilot 2 turns out on the mixture and a 168 main. I have the sparks exhaust. Try 2 turns out on the mixture and see what that does for you. The YFZ's have a weird thing at the throttle setting you are talking about where they go from lean to rich in a matter of a little throttle travel. When I had the same mods as you I was running a 42 pilot 165 main and 2 turns out and it ran great. Also, I hadnt heard anything about the microswitch thing on the carb. I usually slide my airbox out when I am working on the jetting because it makes it much less of a pain to get to the carb.
Isaac
 

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Isaac & laptraffic,

Please guys we need your elevation when you state jetting combos, otherwise it will not be relevant.

Geoff.
 

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Discussion Starter #4
I WAS NOT HIGH WHEN I WAS JETTING MY CARB!!!


oh... sorry about that, Im at 800 feet :)

The stumbling seems wierd to me, it didnt change when I put the 42 in, but I havent touched the air screw. Does the airscrew work in conjunction with the pilot all the way through the first third of the throttle throw? I go fart around with it and see what I get.

I went to 3 different dealerships and all 3 were sold out of 45 pilot jets...
 

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Discussion Starter #5
WOW
That definitely smoothed things out.

Here's the scoop, I didnt know where the airscrew was and so I wasnt adjusting it. 8|

I put the 42 back in and went 3 turns out on the airscrew.

About 90% of that rough skipping is gone, cant believe the difference in how the low end is now.

Can I go more than 3 turns out on the 42 or should I go to a 45 and go in on the airscrew and start over?

Thanks for the help Edgerat I owe ya a beer!
 

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Try going to a 45 and see where you are at. The way that I have noticed this thing going is the richer it is but still clean the harder it pulls. I have never ridden a quad that pulls as hard as this one does.
Isaac

P.S. Geoff I am 200ft
 

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Thanks guys,
now we just have to encourage others. :woo :woo

Geoff.
 
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