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Discussion Starter #1
I wanted to share some results. I feel like I'm getting much closer now.

Previously I was running:

17.5 pilot, 420 mains, stock jet needle with nylon washer
and another shim which got me between the 4th and 5th
notch. Temps around 25 F.

low end - no bog
midrange EGT's - I could get it above 1275
WOT EGT's - 1150 range - maybe a little less

Personal feeling: It was an animal in low end and midrange,
but very flat on top end. The problem was I needed to
get the temps down on midrange before going to smaller
mains. With 1275, I felt I didn't have much of a cooling
down range to go to, if I dropped the mains.

Next Setup:

20 pilot, 410 mains, 942 jet needle with eclip in position 3.
Temps around 25 F.

low end - I noticed a slight bog when riding on trails
midrange EGT's - barely 1100
WOT ETG's - In the 1050 range

Personal feeling: Too rich all the way through the
throttle range.

From there:

20 pilot, 400 mains, 942 jet needle in position 2.
Temps around 25 F.

low end - I did have one time with the bog
midrange EGT's - I could get them to 1220 MAX.
                      Mostly in the 1175 range.
WOT EGT's - 1150 range

Personal feeling: Much better throttle response and sled
was coming to life on top end. I would have put in 390's,
but I didn't have any.

How do I get rid of the bog?
If I could have, then I believe this is the setup I would
run with the 390 mains.

I'm starting to believe that the 942 jet needle burns
cooler than the stock needle due to the smooth taper
rather than the noticable steps in the stock needle.
I can't say that for sure, because I didn't compare apples
to apples.

What I'll try next:

17.5 pilot, 390 - 410 mains, 942 jet needle.

Oh, I did ride my 700 this weekend with RK Tek head and
290 mains. The sled also has DPM. There were two of
us riding and I wanted to get some miles on that sled.
Also, it was nice to jump on one sled and then jump on
the other to compare.

That 700 engine was much crisper than my 800 all
through the throttle range. Its just that noticable a
difference from my 800. The last setup above that I
tried with the 800, I was much closer to the feeling
on my 700. I just believe I needed 390 mains and I'd
be there.

This has been a frustrating Winter for me, but I'm almost
there. And when its done - it'll be time to trade!!!
 

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Thanks for the info. Dont know if this helps but I had a slight bog with the fuel screw turned out 1 turn and it went away when reset to  
1 1/2.
 

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Gunner,

Just as some insight, I would turn thise screws out to 3 turns.  I greatly improves response.  I have also run 360's at 35-40 deg.  It does climb after a little time but hauls the mail until the temps climb.  we have had no snow to try again.  The 942 needles are actually a bigger needle but it may not show up where the stock needles are hot.  I would think around 60mph they would be even hotter than the stock needle.  Just a thaught.  Thanks for the info.  Also, we are running 280 mains on the 700 with no probs.  Real crisp.

GLHRACING
 

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Discussion Starter #4
yes, this lack of snow has us all crazy for test time.

I have my air screws out 3.5 turns and agree with
the response.

I never thought I'd get to 390's let alone 360's!
Wow...

I know what you mean regarding the 942, but I
couldn't get it above 1220 even at 50-70 MPH for
extended periods of time. I suspect the 20 pilot
was adding some fuel - so going back to a 17.5
pilot may reset me all over again.

Thanks for the insight as it is always appreciated.
 

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Gunner,

The 360's were only run for a short distance.  I would not recomend it.  You had better have good fuel when going that low.  We used a well known source of fuel.  It was more of a "lets see how low we can go" test.  I could see 390's at 25 deg but not much lower.  The temp rise in egt's is pretty quick with ambient temp drop ( more oxygen), it shows alot more with this head than with the stock head.  Happy tunning and hope for snow.

GLH
 

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Discussion Starter #7
Didn't look at my GPS, but probably 0-3000 ft.

I was in the Adirondacks, NY and some in PA.

End of the month I'll be in St. Zenon, Canada,
but that's still only 2000 ft.
 

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Gunner,

When you going to St. Zenon.  I will be up there from the 15-19th.  Going up fo some lake testing.  Enjoy the riding.

GLH
 

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Discussion Starter #9
28th - March 4th.. I'm sorry we'll miss each other,
as I'd love to hook up. Actually, I have a few
buddies going from the 17th - 21st. Maybe I
can get away...
 

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This is some great info that is being shared.I have worked with Damon on clutching throughout the winter via long distance(Ak.-NY) and have it dialed in where I can pull a 5 sled length hole shot on an 800 Renegade. But my biggest nemesis is mid range temps also.I have been riding at a 200' elevation at temps of +5F-+25F.With the 942 needle ,I have found it very rich in all of the clip posistions even with 17.5 p/j 's or 20's.When you said your best set up so far was the clip in the #2 position,are you going from bottom to top or vise-versa? Right now my mains are at 450's because of low altitude and temps in the teens.More test and tune to come on Sat.Will be riding with an 800 ZR that has some mods but shouldn't be a problem as I have already smoked two T-Cats.  Even after all the mods I have done to my sled (RKT head,V-force reeds,Dyno-Port pipe,MBRP can,Damons H/C clutch,roller secondary,Digitron,Powder-Lite aluminum front end,and Simmon's skis) I still pull 10.5-11 mpg on the trail.Alot of these factors can be attributed to all the great shared info from this site and the contributors like Damon and Gunner.We all have benefited-thanks to all.
 

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Discussion Starter #11
#2 is from the top. #1 is leanest and #5 is richest.

Do you have an 01 or 02 800? Post your results
against the other sleds. I'm curious.

Anyone know how much cooler the sleds run when
you pull the vents from your air box? I need to try
that out as I want to run 390's and if it gets too
cold, I'll just pull the vent lines off the airbox - becuase
I hate changing jets in the cold and on the trail.

Next sled will have DPM again.. Live and learn.
 

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Gunner,

Just place the foam from the vents in the hood and behind the light and place on top of the airbox, this will be worth about 1.5 jets.  DO NOT remove the lines that are connected to the air box.  I do not care for the DPM and remove it for trail riding.  It only works from 33deg and above.  It does not have an enrichment mode like the old style.  I have found it to be inconsistant and prone to leaks in the tube.  Just my 2 cents.  

zdooz,

Thanks for the compliment. It makes people like myself and Gunner feal appreciated and want to continue tuning.  We don't need compliments all the time but once in a great while is appreciated.  I had not heard from you in a while so glad to here things are working.

Damon
 

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i have a 2002 mxzx 700 does anyone have any carb suggestions on this sled i have vforce reeds dynoport exhaust mbrp can  digitron system it was running 100 degrees hotter on the right cylinder than on the left i had the dealer put in a washer under the needle on the right side now it runs with in 20 degrees. mid range is hot about 1275 degrees and top end is 1170 degrees do you guys think mid range is to hot i have stock jets in carbs whitch is 510n i want to make bottom end leaner and top richer the needles in these are not adjustable. i am also putting a cudney headon this machine with an exhaust restictor and his clutch kit witha 26tooth gear basicllyhis package that he offers with out the porting of the cylinders i am getting that at the end of the season
 

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Discussion Starter #14
I honestly don't think 1275 is too hot, but you have
no room in case it gets colder or you get bad fuel.
I'm trying to get to 1225 throughout my throttle range.
Of course if you ran it at 1275 for an extended period
of time - you could burn it down.

If you are going to put on a new head, then you should
do that first or else you'll be starting all over again.

I'm not sure what needles you have in your sled, but
mine weren't adjustable either (stock), but I was able
to purchase the same needle that was adjustable.
 

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Damon,

Interested in taking my 7 with you? I didn't get to try the other clutching we discussed due to a coolant leak I had to fix. We had quite a few little things happen on Friday and didn't get back to the Cabanon. We had to rebuild one of the other riders primary's on the trail. All of the pins fell out and one of the arms broke. Cobbled it together and made it home 60 miles! I didn't loose a fair race on the lake. If my wife would let me I'd go back but I would not have any testi's when I returned home. LOL. ronzx9

Ron.
 

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Discussion Starter #17
I ordered mine through Ingles Performance. I believe
the stock needles which were adjustable end in 990,
and the smooth taper needles that are adjustable end
in 942. All my documentation is in the garage. If Ingles
can't help you, email me, and I'll look up the numbers
for you.

Ingles has a web site...
 
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