ufo's

[UltraLiteTriple]

anyone tried these, im tring to get rid of a low end bog. i tried different slide cutouts (1.5 to 2.5) made it a bit worse. and i get really bad milage off idle to 1/4 throttle. i have 35 primary jets its in a ultra motor.
thanks Rob

 

[Summitric]

anyone tried these, im tring to get rid of a low end bog. I tried different slide cutouts (1.5 to 2.5) made it a bit worse. And i get really bad milage off idle to 1/4 throttle. I have 35 primary jets its in a ultra motor.
Thanks rob

hi: Tried them in my '99 670x summit, and removed them..... I never could get them set-up properly, and alway seemed to be tinkering with the carbs after installing. Good luck on putting them in your ultra. Theory behind them makes sense, but finding the right combination of jets(including mains and pilots) is tricky. Keep us posted how you make out.

 

[UltraLiteTriple]

also open to any other ideas or suggestions.
thanks summitric for the input

 

[Canuk]

Put them in my 97 670 and remember being impressed, although the seat of the pants-o-meter isn't always reliable, I felt it was a bit snappier. I'm sorry I don't remember what I did to the carbs, it was so long ago.

 

[Modman]

anyone tried these, im tring to get rid of a low end bog. i tried different slide cutouts (1.5 to 2.5) made it a bit worse. and i get really bad milage off idle to 1/4 throttle. i have 35 primary jets its in a ultra motor.
thanks Rob

What pilots are stock? Is your air screw setting correct? Where are your carbs vented to? the airbox?

 

[Dr. Meatman]

drop the needle a clip and see what that does maybe

 

[j.c.higgins]

I'm in the same boat Ultralite, i'm going to be trying them on some 39.5 rounds in an Ultra 800 motor. I'm starting with the 3.5 ufo and a 25 pilot with the airscrew at 3/4 turn out. I'm using a P-8 needle jet and a 6FL14 needle and put the needle 2nd from the top to start. Trying this at 6-8000ft. Plus using a Variflow. From the guys that used these successfully they kept the pilot size in the 15 thru 25 range and airscrew at 3/4 turn. Give the guys at Thunder Products a call i'm sure they can get you started in the right direction. Higgins.

 

[imdoo'n]

The biggest problem is getting the pilot jets leaned out enough, until you get them real lean it won't run right. when they are close then the air fuel needs some attention, leaned out, At each change do a throttle chop and check plugs. when you get it right hold on, instant throttle response and mid range, some top end, but very noticeable mid range. Probably the best $30/cyl you will ever spend. Most guys just won't read the instructions and lean out the pilots enough.
Have put UFO's on two sleds and would do it again, brings grins from ear to ear when set up properly.

 

[UltraLiteTriple]

i preaty sure that 35's are stock size, carbs are vented to pods due to the fact that its in an xlt chassis, air screw is at 1.5 turns, it is also a HTG 800 with triple pipes, it has the the slp needle(not sure what elevation) thats on the top notch. sorry some of the info would have been better earlier
thanks rob

 

[apex69]

i preaty sure that 35's are stock size, carbs are vented to pods due to the fact that its in an xlt chassis, air screw is at 1.5 turns, it is also a HTG 800 with triple pipes, it has the the slp needle(not sure what elevation) thats on the top notch. sorry some of the info would have been better earlier
thanks rob

from what i rember u need to start with half the pilot then go down from there
i did a 600 xlt went from 35 pilot to 10

 

[j.c.higgins]

Start on the rich side and work your way down. Try in the 20-25 range on the pilot, richen the needle 2 positions and set the airscrew at 3/4 turn. Make sure the carbs are synchronized also. Check your plugs and wash and lean out accordingly. Snowest used to have an excellent backlog of info on the Ultra and Ultra bigbores which i reseached extensively before it got wiped clean. The guys mostly all had the airscrew at 3/4 turn
and 15 to 25 pilots. Do you still have the instructions that came with the kit? Higgins.

 

[UltraLiteTriple]

no i do not have the instructions from the kit
Rob

 

[Rob1334]

Sounds like a rich idle circuit, common among Polaris carb sleds...

Good info on here, and most of them are correct. Start by adjusting the idle and low end of your circuit by starting with smaller pilot jets. if 35's came in it, I would maybe try 25 to start with and adjust the rest with the airscrew. Remember, the needles control about 1/4 to WOT give or take, but they won't play much on your idle. Another thing to check is your air pilot jets to make sure they are not plugged, had that problem on my sled at one time. Another nice thing with a smaller pilot they seem to pull over easier when they are warm, and no more black spots in the snow where the exhaust comes out when you are parked.

Good luck with it, I would not go with the UFO's until you have the carbs figured out first, you might just be adding another twist to the problem you already have.

 

[UltraLiteTriple]

not sure if this is part of my problem but i was going to raise my clutch engagement, and i found one of the roller bushings were completely gone this making the wieghts wear into the spider so im gonna rebuild the clutch and see were that gets me
Rob

 

[dooryder]

that could possibly be a problem to that, when my clutch was wore out almost ready to blow, the rpms would dro when i have it gas

 

[jackinthebox]

Like most have said drop the pilot in half,lower the clip and that's ur starting point,when there dialed they make a huge seat of the pants difference.

I threw them @ 96 zrt 600 and it took me a good solid month of tinkering,shaving the slide,hell i even think i drilled the nozzzle. but mid range was pretty wild....man that was a few years ago now....

 

[xcya]

OK guy's here it is. The first UFO'S that came out had a problem. The hole that the jet needle goes through was TO SMALL. This caused to much fuel to be picked up through the NEEDLE JET. Find out what size that hole is useing a numbered drill bit and drill it out BIGGER.:d This will cause less of a draw bringing up less fuel at IDLE. Going up one or two sizes WILL fix this bottom end rich mixture problem. Also, when you install them, use the one size smaller cutaway than what you have stock on your slides and then file the slides down to mach the UFO.

 

[magnet]

throw them into the trees put carb back together and ride hard. really is the extra .2hp worth the freakin headache to get it? jmo