2 mpg's, I'm a newbie and need help.

[shokaconbite]

This is my first post here but I've got a new sled this year that started out getting 4 mpg's. I thought this was bad so i took it to the dealer. they said dpm wasn't hooked up so they did that and said they adjusted the secondary clutch. I take it out and it only ran at 7500 rpm at "6" and Now it gets 2 mpg, i ran out in 22.2 miles. I am running it without an outer airbox which is why the dealer says it is messed up. I'm gonna try and get an outer airbox but i find it hard to believe that thats the only issue.

I've been told its a float thats stuck but it never really floods, it does bog on downhill slopes.

I've been told to jet it down to around a 360, im at 9000 ft.

I've also been told that clutching can make a big difference on mpg's.

What do you guys think?

 

[Brotha NOS]

Check your choke

I agree with your dealer. Not running an airbox screws up your DPM readings and causes it to screw with your fuel feed rate. The other thing that I believe may be screwing up your fuel consumption is that the choke is too tight. You should be able to pull the entire switch up and down 1/4 - 1/2 inch. If it is tight it will always be applying partial choke and feeding fuel. Loosen your choke cable on the carbs to correct this problem.

 

[Insaneboltrounder/sjohns]

sounds like my 1100 tcat with the bored carbs

 

[Macattack]

what sled are you having issues with?

 

[bigcat_ak]

First- WHAT SLED ARE WE TALKING ABOUT??? sorry.

To only get 22 miles per tank, gas has to be running out on the ground!!! I run pods and a DPM with no problems. Just have to do it right. Really need to know what sled to help much.

 

[ridewell]

Whats so secrete about what your sled is?

 

[shokaconbite]

Whats so secrete about what your sled is?

its an 03 mxz converted to a longtrack. its got a 151 now. an 800.

 

[Brotha NOS]

Are you still geared like an MXZ or did you gear down. An MXZ is built for speed not for climbing. The MXZ came out with 26/43 gearing where as the Summit 151 came out with 19/43 gearing. If your gearing is too tall the belt will never ride all of the way up on your primary clutch and you will never achieve RPM under load.

 

[shokaconbite]

I haven't checked the gearing

i haven't checked gearing although, it definitely doesn't go as fast as my buddies sleds, they are on summits. would that type of gearing on a longtrack kill mpg's?

 

[shokaconbite]

do the gears say on them what number they are, or do i have to count teeth. also where would I round one up if i did need to get one?

I've opened up the chaincase on my old sled ( a polaris xlt). is it pretty much the same process or am I looking at something more complicated when switching it out?

 

[Brotha NOS]

Gears

Some gears are written on and some are not so you may have to count them. It is as easy to pull the cover off as your Polaris was. If you are geared like an MXZ you will likely need a smaller chain too. Any ski-doo dealer should have everything you need to regear if necessary. If you are too high geared it will cause the clutches and engine to overwork and definetly affect fuel effeciency. When your clutches were set up for altitute you should have been able to get higher RPM but if your gearing is to high you will never see max RPM under load. I am not sure what all has been modified on your sled so it is hard to nail down your actual problem. Clutching, Gearing, Jets, Pilot Jets, needle position DPM ,Plugs all affect fuel economy. Keep checking on all the suggestions you get, one of them will work. Reading about your bogging going down hill I would tend to think that or your needles are set too rich on your carbs, drop your neddles one position. Check your pilot jets too if they are 20's drop them to 17.5. As for your jets...check your plugs, If it is fat your plugs will black, Jet down until they are golden brown (white is way too lean and you will blow). The MXZ carbs are different than the Summits. Check out the parts section at skidoo.com and check out all the differences between the 2 sleds.
I would try to find out what was all done to your sled from whoever you bought it from. It will help nail down your problem.

 

[shokaconbite]

thanks for the help

thanks guys, and brother nos for all the help. i suppose i've got all sort of things to check out. I appreciate all the help.

 

[shokaconbite]

jets and such

so i checked out my jets, they are 380's, my plugs are black. How much lower should i jet it? Im running around 8 - 11000ft. I also loosend my choke cable too so i can pull it out more, although it didn't seem to be engaging the choke at all.

Im gonna regear it too. The dealer recommended a 21 tooth on top, and a 74 chain, but they werent sure if i needed the 74 or 72 link. does anyone know for sure what link chain i should be using?

 

[Brotha NOS]

chain and jets

Your current chain should be a 76. With a gearing of 19/43 the chain is 72 link and a gearing of 22/43 is a 74 link so I would use a 74 link chain. Try 360 jets, check your plugs after a run and carry lower jets with you and change them on the hill if necessary. Hope it all works 4 U.

 

[sledhead-also]

If this sled has been left stock, it has 26/43 gearing and a 72 link chain:

http://12.2.215.22/pub/default.asp?...Lang=EN&brands=SKIDOO,SEADOO,ATV,SPORTBOAT,EJ

This according to the Doo parts list. If you are running elevation, I'd highly recommend going to 19/43 gearing. I ran that (stock gearing) in 02 800 Summit and it worked very well! That should fit with a 72 link chain, I think. You would have to install and see if the adjuster puts too much bend in the chain. Too much slack taken up by the adjuster causing a large "V" bend in the chain will cause a parasitic power loss to friction and cause premature chain wear. Just my $.02

s-a

 

[NoSecondChances]

This is my first post here but I've got a new sled this year that started out getting 4 mpg's. I thought this was bad so i took it to the dealer. they said dpm wasn't hooked up so they did that and said they adjusted the secondary clutch. I take it out and it only ran at 7500 rpm at "6" and Now it gets 2 mpg, i ran out in 22.2 miles. I am running it without an outer airbox which is why the dealer says it is messed up. I'm gonna try and get an outer airbox but i find it hard to believe that thats the only issue.

I would still suspect something else as well as what was already mentioned. I agree with bigcat_ak, to only get 22 miles on a tank, that sled shouldn't even run it is so rich. Go to www.stboni.com and go into the service section, get yourself the high alt specs for your sled, drop the gearing as suggested, change the clutching a little, and get an EGT or Air/Fuel gauge so you can get it tuned and jetted right. If you are running without an airbox, you are probably running really rich. I find it hard to believe that the dealer "worked" on it and it still runs that bad. Are u sure that your floats aren't sticking and the extra gas isn't running out of the bowl overflows and onto the ground? How many plugs have you fouled?

 

[hiboost woody]

if you're not running the air box you won't get your DPM to work right on that sled. Gear down to 19/43 and start out at 270 mains with no dpm and it should run well. just unplug the dpm from the mpem box. put hollow pins in the clutch and run in 5 or 6 on the clickers. if you're gonna run high alt most of the time i would put the summit ramps in the primary and secondary. i have a 03 mxz setup with a 144 and it works good.

 

[shokaconbite]

Update as of now

Alright, well i switched out to 360 mains today and am going to run it tommorow. i also got 350 mains to try if its still rich. 270 seems really low, although i really know nothing. are you talking about a rev mxz?

I've only fouled one plug so far but they are super black. I'm going to try and get an outer airbox so i can hook up the dpm, but for now i will disconnect it.

as far as gearing i was going to gear it with a 21T and a 74 link chain. Should I run a 19/43 instead with a 72 link?

I've got no fuel leaking.

 

[Brotha NOS]

Size of drivers?

One more thing to check before you gear is to check what size of drivers you are running? It is all about the correct ratio. You MX Z had a 9 tooth driver and if you still have 9 go to the 21 tooth gear and if it has a 10 tooth like the summit go to the 19 tooth. Hope this clears things up for you.

 

[shokaconbite]

do you guys know if my gear would be a 13w or a 15w. its an 03 mxz rev x 800.