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Hello,
I have a 99 xc 700 and it is bad on gas. what would i need to do to fix this? i have heard that the factory jets are 2 big. I am somewhat mechanicly inclined, but never really worked on a sled b4. would I be able to tune the jets myself? if i can where would i go to find out how to did it properly?

Also, I have big problems hooking up. the track just spins. i have tried adjusting the rear shock but it did not seam to help, anything i could try?

I'm thankful for any help. Thanx
 

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Dave,

The rear shock has little or nothing to do with track spin.

Track spin happens because you are not able to transfer the weight of the front of the sled to push down the track. On a sled with good weight transfer the entire front end weight is used to hold down the track and the end result is skis lifting off the ground.

your sled has the Xtra-10 suspension, so here is a breakdown of the adjustable items and what effect it has.

1. Front limiter strap: These alter the angle that the front shock pre-loads your track. The more the angle is 90' to the track, the more track pressure. Adverse effect is less effective front travel.
2. Front shock spring pre-load. The more preload, the more track pressure. Adverse effect is stiffer ride.
3. Rear torsion springs, The lighter they are, the more weight transfer (track pressure). Adverse effect is easier bottoming.
4. Rear limiter strap, The looser it is, the more track pressure you have. Adverse effect is easier bottoming
5. RRSS blocks. The farther they are to the rear torque arm, the more weight transfer (track pressure). Adverse effect is loss of coupling with the front shock when landing off a jump and thus bottoming

As you can see, each and every setting is a comprimise in ride quality, the trick is to set the suspension up for your riding characteristics.

If you did each of these steps, your sled will never touch the ground in front and you will miss every corner. You see weight transfer takes the weight off the skis and you lose steering control.

Start with a few steps at a time. Try moving the RRSS block first and loosening the torsion springs. If you don't like this, Re-set them and try adjusting the front limiter straps and preload.

Or do a combination of things. Testing a tuning suspension can be just as fun as time trials and at the same time it gives you a chance to experiment and set the sled up to the way you ride.

The best setting for MY ride is for the front to lift 2-3 inches from dead stop. this gives me enough front end ski bite during normal riding and at the same time gives me a real boost on hard acceleration.

Good luck!
 

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:withstupid: on the suspension set up.

As far as carb tuning ask your dealer about the needles in your carbs I got new ones for my 99 600 and 3 friends with 00 700's got them too it really helps with gas mileage. I don't have the part number on hand but they're easy to change. depending on the temps where you are you may also be able to down jet a bit, I'd suggest picking up a carb tuning handbook to explain the jetting/testing process, you don't want to lean it out too much or you'll end up frying a piston like I did in my old Mach 1.

Good luck with the tuning the sport becomes more fun as you start tinkering with the machine.
 

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Nice job there Mad...

AL
 

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My 00 700 has been "massaged" pretty good and last year when riding with a friend on his 02 700 (which are supposed to be a lot better on gas -stock) we were consistently within 1/2 gallon at every fillup.

First, my sled is studded 144 down the middle so track spin isn't as big a deal.

I've made the following mods:

1) SLP boost bootle and power paks. I really don't how much these help on their own. With the low snow last year I commited the cardinal sin and ended up making several changes with only some short spins in between. They do seem to clean up the dead spot right off of idle.

2)1370g needles. Stock is 1368g. A lot of people have found that the 1371g needles work well, but on my sled these were just too lean down low and I couldn't get the idle right. These needles basically lean out the idle and first 1/4 throttle. The higher the number in the last two digits, the leaner it is. There is a lot more to the needles but just know you can try them both. I don't have part numbers but your dealer should be able to get them.

3) I'm at 1300' and usually ride between -10f and +25f. If I remember right, I'm running 180/185 jets Stock is 190/195. I think you're pretty safe using these jets as that seems to be what most people run. If you're unsure, you should buy a "bend-a-light" to check piston wash. The light is sort of hard to find but if you do a search on the web you should be able to find a place that sells them. They're about $17. www.hiperf.com is one place. See if you can find some back issues of snowtech magazine. Their tech help is awsome and last year they had a whole article about pistion wash and jetting.

I've got close to 2000 miles on my mods without a hitch. No matter what you do the 700 is always going to be hard on gas. If that is your main concern, you'll have to really decide if its worth it. I still only get around 10 mpg with mine, but that's hard riding and like I said is really close to my friend's '02. The biggest benefit is that it's noticably crisper throttle reponse.
 

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Thanks AL!

I find the factories (all factories) really don't give enough info on suspensions. They don't even explain the "why" of their components!

I mean the Xtra-10 and Xtra-12 are suspension marvels but no one except a few trained individuals can get full potential out of them!

And those set-up charts are for the birds. If you really want to tweak your suspension and set the sled for your ridding the only way is to learn the basics.

Look at what I wrote, took 3-4 minutes, but miles more comprehensive than the "rider weight charts" that are glued to the inside of the hood. Sometimes I think the Factories think the buying public are morons. I hate not understanding how something works. I guess thats why I'm a mechanical Engineer - I don't accept "recommended settings"
 

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i remember reading in a supertrax magazine about this sled and in the read-valve section or something like that polaris said that you could safely jet down two full sizes on these machines
 

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to fix your milage problem,Tempa flow,1371g needles 190-185 jets ,this is run at 700 ft and as cold as you dare be out,11-12 mpg.
 
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