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UFO's om a ZRT 600

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Team, I have a 99 ZRT600 and have been planning on installing UFO's. Anyone have sugestions? I understand Tuning can be a pain. Anyone have one set up and would like to share there tricks / Jetting?

My sled is stock except for the gutted air box and clutching.. :dunno:
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Originally posted by abagoz@Oct 4 2005, 05:04 PM
Team, I have a 99 ZRT600 and have been planning on installing UFO's. Anyone have sugestions? I understand Tuning can be a pain. Anyone have one set up and would like to share there tricks / Jetting?

My sled is stock except for the gutted air box and clutching.. :dunno:
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I cant help you on actual setup.. however I do remember reading in one of the snow mags about messing with the pilots and not to do it. Something about drilling a hole somewhere instead of messign with the pilots to get it to idle.. ?? Damn it I wish I knew where that copy is. All my mags are boxed up at the moment. I have a ton ranging back to the early 80's. If I have some time I will try to find that and scan it for you.
The directions are good, they give some baselines. I have them as well, but I haven't decided if I'm going to install them or not, I have a set of flats also that I may put on instead. You need to drop the pilots quite a bit and raise the main jets. I have Pilots in sizes 10-20 to try if I use them. I was going to go from 35-20 to start and work down from there, bump my mains up from 360 to 370 (I also have a tempaflow, if you don't have one, your mains should be at 320 or 330 probably).

1BigCat is referring to drilling holes in the pilot jet if it won't idle correctly. The same guy makes these who makes Thundershift, they support their products well, and will probably have a baseline setup for your ZRT 600.

EDIT: It is the Needle Jet that needs to have tiny holes drilled into it, not the pilot jet.
If I remember correctly I am running 330's. My sled is at my cabin or I would take a quick look. I don't mind doing a little tuning but I just don't want to spend all winter to get it right. I guess I would like to have a set up that works from the get go and then tweek as needed.
Put them in, you'll feel an increase in your low to mid pull. Have them in my 97, what a difference. If your running 40 pilots they tell you to cut it in half, put in a 20 pilot. Im currently running 10 pilots and would like to put smaller, but can't get any smaller. What 1bigcat was saying about not idling and drilling the UFO is true but on the 900 and 1000, bigger cc sleds. I couldnt run the reed spacers with the ufo's because it did run to rich at idle. Main jet leave what your running currently and try it. I personally would recommend them. Any other questions just ask.
Just drop the pilots to 10 to 20 range and leave main's and needles alone? Pull out my Reed spacers..

This will get me in the ball park.. Have you had them in for a while? no issues, plug fouling...
You will use more gas so filling up between pumps will be more often. You have to drill out the Needle jet not the pilot jet. Why would you drill out the pilot jet??? To make it more rich??? Anyway, they arent a easy thing to tune, they will take some time, more than its worth IMO. Yes they work but for the time involved and the fact of worse gas mileage I dont know if its worth it. If you have time to mess with them then go for it but if your like me I would rather ride than mess with my carbs on my seld multiple times before they are right.
I wasnt as clear as I wanted to be I guess. I did say not to mess with the pilot but drilling a hole somewhere else, if you re read it. I just remember them saying not to mess with your piolots but to drill a small hole somewhere else. I am currently looking through my 200+ back issues I have boxed up trying to find the artical.
Originally posted by gpxsrxracer@Oct 6 2005, 08:28 AM
Presto! http://www.thunderproducts.com/u_f_o_air_bleed.htm
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There ya go.

Thanx... saves me allota flippin pages. :div20:
Originally posted by gpxsrxracer@Oct 5 2005, 10:26 AM
You will use more gas so filling up between pumps will be more often. You have to drill out the Needle jet not the pilot jet. Why would you drill out the pilot jet??? To make it more rich??? Anyway, they arent a easy thing to tune, they will take some time, more than its worth IMO. Yes they work but for the time involved and the fact of worse gas mileage I dont know if its worth it. If you have time to mess with them then go for it but if your like me I would rather ride than mess with my carbs on my seld multiple times before they are right.
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How can you use more gas if your lowering your pilot jet size by half or even more, and leaving the rest of your jetting alone. Your not drilling out any of your jets, When we talked to thunder products about the ufo's on a friends 900 t-cat about running rich at idle, they said to drill out the UFO, where the needle comes through the slide and ufo. lets say where the needle comes through the ufo is 1/8th inch, they said to make it a 1/4 inch and go up in small increments from there. We ended up with a 5/16th in the ufo.
But if he's running them on a 600 he will have no problem like this.
ABAGOZ If they are set up correctly you will get the same or better mileage than stock and much better throttle response and power. You might consider temp gauges to help you tune. UFO's are not for the faint of heart but they work when set up correctly.Peace, beeler.
Originally posted by beeler@Oct 7 2005, 03:12 AM
ABAGOZ If they are set up correctly you will get the same or better mileage than stock and much better throttle response and power. You might consider temp gauges to help you tune. UFO's are not for the faint of heart but they work when set up correctly.Peace, beeler.
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Better mileage??? ha ha ha!!! I haven't found anyone who gets better mileage than a properly tuned stock carbed sled. If they say they are getting better mileage they are usually full of it.

Most people end up running bigger main jets when they lean out the bottom end to prevent burndown. Usually 2-3 main jet sizes.

The ufo's are for better throttle response, not better fuel mileage.
Originally posted by gpxsrxracer@Oct 7 2005, 12:17 PM
Better mileage??? ha ha ha!!! I haven't found anyone who gets better mileage than a properly tuned stock carbed sled. If they say they are getting better mileage they are usually full of it.

Most people end up running bigger main jets when they lean out the bottom end to prevent burndown. Usually 2-3 main jet sizes.

The ufo's are for better throttle response, not better fuel mileage.
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If your starting out with a properly tuned carb to begin with, and ad the ufo's, which in turn your leaning it out even more(smaller pilots,I had to lower my needles). The ufo's are atomizing the fuel much better then a stock slide.
Your main jet is staying the same.
I have them in my drag sled and my 97 zrt 600 trail sled, my dad had them in his pantera 800(sold it) friend had them in his 900 t-cat(sold it) and another friend has them in his 98 zrt 600. If you can tune a carb their no problem to tune with the ufo's.
I have a spare set of Flatslides from a 2001 ZRT 600 if your interested.I put a set of Flatslides on my 99 ZRT 600.It runs good and is alot easier on the right thumb on long trail rides.SS
Originally posted by Bonestock?@Oct 7 2005, 12:54 PM
If your starting out with a properly tuned carb to begin with, and ad the ufo's, which in turn your leaning it out even more(smaller pilots,I had to lower my needles). The ufo's are atomizing the fuel much better then a stock slide.
Your main jet is staying the same.
I have them in my drag sled and my 97 zrt 600 trail sled, my dad had them in his pantera 800(sold it) friend had them in his 900 t-cat(sold it) and another friend has them in his 98 zrt 600. If you can tune a carb their no problem to tune with the ufo's.
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So are you saying you got better gas mileage over a properly tuned stock carbed sled??? I have never personally saw anyone get better mileage over stock. Better performance yes but better mileage no.

If so how many miles did you get per tank between fillups and then with the ufo's.
Check out this link, this is just one of many that all basicly agree an the same results, better performance but more gas consumption. http://web.telia.com/~u97016182/tech/ufo.htm
Originally posted by abagoz@Oct 4 2005, 05:04 PM
Team, I have a 99 ZRT600 and have been planning on installing UFO's. Anyone have sugestions? I understand Tuning can be a pain. Anyone have one set up and would like to share there tricks / Jetting?

My sled is stock except for the gutted air box and clutching.. :dunno:
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Heres the original post, I dont think he was looking for better milage.
But what ever, I cant personally tell you before and after because it didnt concern me to begin with. But if your lowering jet sizes, theres less fuel going thru the carbs. The ufo's are helping atomizing the fuel as its entering the cylinder, burning all the atomized fuel and adding performance.
Originally posted by gpxsrxracer@Oct 9 2005, 09:34 PM
Check out this link, this is just one of many that all basicly agree an the same results, better performance but more gas consumption. http://web.telia.com/~u97016182/tech/ufo.htm
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Read the link after I wrote my last post. And to tell you the truth on my 600s I never noticed a big gas consumtion from before or after installing the ufo's. But I could say that on my friends 900 there was a slight difference. But we are talking about a 600 here.
I still say its worth the time setting them up.
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