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Anyone done the UFOs on the 98 XCR 440? If so, do they work as advertised, what did you end up with for jetting, and was it worth the effort?
 

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NickJ has them on his 99 GenII "same engine" Not sure if he got out for run yet on it but on the stand he said he noticed a differece. I think he also has a temp-a-flow installed. He said the directions are pretty straight forward and simple to do. I don't think it really puts the jetting off, only to drop the pilot half the size.
 

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i read up alot about them and decided the work involved was not worth it, would rather spend money on reeds 1st.
 

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Ya I got them in, but still dont have them tuned quite right. Jetting looks perfect and runs good from idle on up, but my mains are way too rich. I want to swap back down to the 360s and go from there. I was also lean in midrange (possibly, hard to tell, new plugs always read light, but better safe then sorry till i get some miles on them)even after raising the needle a notch. I am now on the very bottom setting, and getting that nice light cardboard brown from 1/4 to 3/4 throttle runs. I have heard though that if you are on the bottom most notch its time to move to a bigger needle?

On WOT runs across the lake, right around 1 mile, my plugs are a little dark but soaking wet. Everything but WOT they are dry and perfect color. This is with the tempaflow leaned out a bit too. I will probably switch back to the 360s, I have 370s in there now. Like i said though, I would have had this all figured out for ya guys but lack of snow really puts a damper on things around here.

My jetting may be a little on the rich side when done, but it should be good for someone who doesnt want to be changing jets all the time. With the tempaflow I will be able to lean it out some there to get it spot on, but it should still be pretty good.

I think I will end up with

25 Pilots
1.5 turns on airscrew
needle in bottom (possibly 1 up) setting
360 mains (stock)
 
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