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Discussion Starter #1
Here is my story. I acquired an 08 Teryx with 109 hrs on it. Needless to say, it did not quite perform up to my standards. I have ordered and installed Muzzys, non-programmable CDI, Uni-filter with adapter, Dalton Clutch and HW's carb kit.

Upon the installation of all of these components, I went with HW's recommendations (for parts installed and elevation 5300 ft.) for main jets to get me started. I have read and understand the jetting process working from WOT back to idle. I installed 144 front and 146 rear. Initial WOT readings with A/F monitor were 10.3 in the front, and 9.5 in the rear. That seems extremely rich to me, so I removed those jets and installed the smallest jets that came in the kit. 136 in the front and 138 in the rear. Readings came up, just as I had expected with 11.7 in the front and 11.3 in the rear. Before I go any further, let me just say that the machine runs so much better all ready. For some, these numbers may be acceptable, but I would like to dial them in much closer. I had to order some smaller jets. Based on my math from the adjustments that were made previously, I thought that I would end up somewhere near 130 in front and 132 in the rear to get me around 12.5. I ordered jets from 126-134 just in case. While waiting for the jets to arrive, I decided that I would check the valves. I found that valves to be tight, so I adjusted them to .005 intake and .008 exhaust.

I received the new jets and decided that I would start with the smallest jets 126 that I had ordered. With 126's intalled in the front and the rear, I now have WOT A/F readings of 11.5 front and rear. These readings are taken with the stock air box and lid with HW TPI valves installed and both fully open. The machine seems to run pretty good, but I would still like to get my numbers somewhere around 12.8 or so, because I ride up in elevation from here.

Like I said, there really isn't a problem with the way the Teryx runs. Since I have an A/F monitor, I would just like to get things closer. I am not sure if other people that ride in higher elevations are experiencing similar results. I don't know if I should order smaller jets, or is there something that I may be missing. It sure seems that I might have better performance if I was running main in at least the mid 130's range or up. Any advise would be greatly appreciated. My instinct tells me to order smaller jets, install them, and trust my Air/Fuel monitor. I am really curious what might have changed in between my initial readings before I ordered the new jets, and now that the new jets are installed. I calibrated the A/F monitor before I ever used it, and thought that something might have happened between the sets of readings so I recalibrated again, but I did not have to adjust the calibration the second time.

Let me just say thanks in advance for any advice!
 

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Something is up, your not getting enough air for some reason, that is very small of a jet for what you have but yes you should trust your gauge.

Maybe the slides are not opening all the way or the throttle is not opening all the way. But for some reason you are not getting enough air.

Is the screens in exhaust plugged up?
 

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Discussion Starter #3
I am still in the process of working this one out. Throttle blades are synchronized and open fully, as do the slides. I have removed both TPI valves, left the holes open, and jumped up to 132 jets. I am now near 12.3 or so at WOT. When I slowly roll into the throttle to check for needle position, i come up with high 10's and low 11's. Clip is on groove #1. It appears that I may be one of the unlucky ones that will have to replace the needle jet with a smaller one.

I have noticed a few things that have changed since since I removed the TPI valves and added larger jets. I will say that there is a noticeable difference in power and I mean that in a good way. Even though I have not really reached my ideal goal for jetting, as I am still to rich throughout, I have become somewhat concerned because I hear the fan come on more often now. It may be a direct result of it running better and me running it harder. How often does your fan run? Mine doesn't seem to run very long, but it seems to kick on what I would consider fairly often. What are the stock size needle jets for the Teryx?

Thanks again for your feedback.
 

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our altitudes are different, but for comparisons... i had the same mods (different clutch) and i was running a 146 front and a 148 rear. i agree with todd... not enough air...
 

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Discussion Starter #6
The instructions with the Muzzy's say to run the machine at least an hour before you install the spark arrestors. I still have not installed them, so I wouldn't think it would have anything to do with that. Just out of curiosity though, if the choke cable was not adjusted properly, what circuits would it affect? Would it affect everything but WOT, or would it really only affect idle? The reason that I ask is because I think the both of you are right. The machine ran pretty good before I adjusted the valves, and this was with both TPI valves installed. I just wonder if maybe flipping the carbs are there sides while still having the throttle and choke cables connected might have bound the choke cables up. Can anyone tell me what the stock size for the needle jet is? If I can't figure anything else out then I will need to change to a smaller needle jet.
 

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You just made me think of something about the choke. If the chokes or the one you have the air/fuel gauge attached to has the choke on slightly it will surely cause it to run rich and have you keep jetting down.

Check the Y cable in front of the shifter. There is some heat tape wrapped around it and two wire ties around it. Sometimes the cable sheath can be pulled out of the Y causing one or both of the chokes on.

Todd
 
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