Ski-Dooin' it
Expert
so i have been out riding my yamadoo, working on detail stuff, gotta cut a small chunk of header out and reshape it as its to close to my brakes... and thye get heat soaked and stop working which is SCARY!!!
right now i want to work on getting my carbs worked out better. it runs halfway decent, but its got some bizzare hiccups/sputters.
current carb setup is 120 mains and the rest stock. i have to still crack my pitot jet style bleeder valve a little or it misses up high badly and just wont pull full rpm. if i crack it open a hair it clears out, needs to be pretty open to fully clear out and pull rpm. i dont have any wideband numbers right now as my sensor wire fell down on the brake rotor and cut the wires, but im getting a new one asap, BUT, im used to what it does and know what is a rich gurgle or a lean pop.
2 main things i want to adress right now. first is once the sled is warm it will NOT idle down, it idles at 3500 or so when its at running temp... if i shut it off and let it cool way down its fun, but once its hot it idles just below engagement. afr reading was right around 12.5 when it does that... choke will sputter it down then it cleans out and hops right back up again.. strange.
second thing is i found the fool who i bought my BOV from had the soft and the hard springs in it, so i could never get it to open, now i have the soft on in and i have it so it comes on nicely.. not open unless you back out of hte throttle pretty quick. problem is now that that happens, when i chop the throttle, the thing seems to load up BADLY.. if im WOT then chop the throttle it sputters for a few seconds then cleans out. this is scary when you need power fast!! used to load up just a little, but the BOV made it worse, which is strange.
and my last thought on the still rich top end was, could clipping my carbs springs down a tiny bit help em open just a touch more thus cleaning the top end out?
when it runs down the trail wot, if you stab the beast at 60... the skis pickup and you better hold on. not bad for 10psi!!
right now i want to work on getting my carbs worked out better. it runs halfway decent, but its got some bizzare hiccups/sputters.
current carb setup is 120 mains and the rest stock. i have to still crack my pitot jet style bleeder valve a little or it misses up high badly and just wont pull full rpm. if i crack it open a hair it clears out, needs to be pretty open to fully clear out and pull rpm. i dont have any wideband numbers right now as my sensor wire fell down on the brake rotor and cut the wires, but im getting a new one asap, BUT, im used to what it does and know what is a rich gurgle or a lean pop.
2 main things i want to adress right now. first is once the sled is warm it will NOT idle down, it idles at 3500 or so when its at running temp... if i shut it off and let it cool way down its fun, but once its hot it idles just below engagement. afr reading was right around 12.5 when it does that... choke will sputter it down then it cleans out and hops right back up again.. strange.
second thing is i found the fool who i bought my BOV from had the soft and the hard springs in it, so i could never get it to open, now i have the soft on in and i have it so it comes on nicely.. not open unless you back out of hte throttle pretty quick. problem is now that that happens, when i chop the throttle, the thing seems to load up BADLY.. if im WOT then chop the throttle it sputters for a few seconds then cleans out. this is scary when you need power fast!! used to load up just a little, but the BOV made it worse, which is strange.
and my last thought on the still rich top end was, could clipping my carbs springs down a tiny bit help em open just a touch more thus cleaning the top end out?
when it runs down the trail wot, if you stab the beast at 60... the skis pickup and you better hold on. not bad for 10psi!!
dirk_03
Expert
Rich
My turbo vector is doing the same thing when I chop the throttle. It acts like it floods momentarily. If I chop it hard enough and not get back into the throttle it will die. This makes it pretty inconvient. So i am interested in thoughts on what can rememdy this. Also I am still pretty fat at WOT so maybe that has something to do with it.
Also If your fat up top and can't get it leaner have you tried turning down the fuel pressure?
My turbo vector is doing the same thing when I chop the throttle. It acts like it floods momentarily. If I chop it hard enough and not get back into the throttle it will die. This makes it pretty inconvient. So i am interested in thoughts on what can rememdy this. Also I am still pretty fat at WOT so maybe that has something to do with it.
Also If your fat up top and can't get it leaner have you tried turning down the fuel pressure?
Rx1M5
VIP Member
Generally when you see the throttle chop problem it's because the floats are set too high in the carbs and it floods. Does your sled stall going down a steep hill, cause thats a sure fire sign that your floats are too high. I can't remember what I ended up setting mine to but once I did the problem went away. If you do a search on "float height" or "flame out" you should find what you need. Does your sled have the mountain float bowl update as there are still some sleds kicking around with the old old float bowls. You also need to adjust your riding style with these motors as you can't be ON/OFF like a 2 stroke you need to learn to feather the throttle when possible and anticipate letting off while keeping the turbo spooled. This is really important when you let the front end down going over the top or coming off a huge wheelie. I see it all the time when a first time rider trys my sled they stall it yet it never stalls on me.
120's seem super lean to me. I run 140's at 12-16 lbs. I've never heard of anybody running a jet that small, I know your riding area and it's basically the same as mine. IMO there is no need for that whole pitot thing cause once your jetted right you don't ever need to touch them they just always run the same.
Rx1M5
120's seem super lean to me. I run 140's at 12-16 lbs. I've never heard of anybody running a jet that small, I know your riding area and it's basically the same as mine. IMO there is no need for that whole pitot thing cause once your jetted right you don't ever need to touch them they just always run the same.
Rx1M5
Ski-Dooin' it
Expert
as far as jetting, it has a LOT to do with the pressure signal your float bowls get and static vs dynamic pressure. mine gets RAMMED full of air right out of the mouth of the turbo, i could mess with the pressure port setup, but i can just bleed of pressure and run tiny jets. I know multiple bender setups that run the bleeder and 120-125 main jets. This i know im correct on this as i have played with it enough getting it to work. think I hamre more time into float bowl pressure signal setup then most have spent time on there sled.
as far as setting the float bowl height.. i think im gonna have to check that, i have the mountain bowls. so very possible that could be my issue. and with the chopping the throttle, i was messing with it going down the trail, and even if i just very slowly eased out of it from WOT, when i finally let it down to idle, it would load up some, so even if i tried as hard as i could, it would still load up to some extent.
also, could that be affecting my idle? if they are set to high? my sled idles insane high when its warm, but going down hill it seems to be gurgling really bad, only reason it wouldnt be stallign is the idle goes to like 3500 when warm!!
as far as setting the float bowl height.. i think im gonna have to check that, i have the mountain bowls. so very possible that could be my issue. and with the chopping the throttle, i was messing with it going down the trail, and even if i just very slowly eased out of it from WOT, when i finally let it down to idle, it would load up some, so even if i tried as hard as i could, it would still load up to some extent.
also, could that be affecting my idle? if they are set to high? my sled idles insane high when its warm, but going down hill it seems to be gurgling really bad, only reason it wouldnt be stallign is the idle goes to like 3500 when warm!!
Ski-Dooin' it
Expert
any thoughts on my insane high idle?? could that be my floats are to high and it pumps fuel past and it acts like the choke is on?? just guessing.. trying to get answers.
mmmkokanee
Expert
set your float level to the max 15mm i think?
Do a search on here and you will find the page from the service manual showing how.
Mine would flood out after a big wheelie or jump and i only had to adjust 1mm more to get rid of this.
It would stay on high idle unless you adjust your idle down to 1300-1400 rpms and now will only high idle when you let off the throttle for 1 or 2 seconds and then idle itself down.
Check your air idle screws in the bottom of carbs...mine are 2 turns out from fully seated.
Good luck
Chris
Do a search on here and you will find the page from the service manual showing how.
Mine would flood out after a big wheelie or jump and i only had to adjust 1mm more to get rid of this.
It would stay on high idle unless you adjust your idle down to 1300-1400 rpms and now will only high idle when you let off the throttle for 1 or 2 seconds and then idle itself down.
Check your air idle screws in the bottom of carbs...mine are 2 turns out from fully seated.
Good luck
Chris
Ski-Dooin' it
Expert
So are you saying the high idle can be affected by the float bowls being to high?? I will mess with mine, i need to swap some stuff out, so that should make it easy anyways... I have a service manual, and will do a quck search for some reading.
Thanks for the info, it would be nice to get ride of the high idle as sometimes it gets to the point it starts to push on the belt a little which can be kinda scary... thats why i always wear my teather on this sled!!
Thanks for the info, it would be nice to get ride of the high idle as sometimes it gets to the point it starts to push on the belt a little which can be kinda scary... thats why i always wear my teather on this sled!!
givemeaboost
TY 4 Stroke Junkie
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Are you sure that it's not in the throttle cable? Did you use the ski doo bars and flipper or the rx1 stuff ? Ken...
mmmkokanee
Expert
try to set your idle down with the big gold screw where the throttle cable goes into the carb rack.
Also make sure the throttle cable isn't tight...needs a tiny bit of free play. Does it rev up when you turn to one side?
The float level never affected my idle...just caused flooding on hard landings.
Also make sure the throttle cable isn't tight...needs a tiny bit of free play. Does it rev up when you turn to one side?
The float level never affected my idle...just caused flooding on hard landings.
Ski-Dooin' it
Expert
i haev all yamaha stuff.. cable is VERY long.. and has some excess slack in it.. again, only happens when it warms up.. could be my idle screw is messed with.. might hav ehappened... i forget sometimes.
more stuff to play with.
more stuff to play with.
Ski-Dooin' it
Expert
Alright.. gonne bring this back to the top as of course. I have more questions.
I installed new carb boots and my wacky idle went away..
currently letting my buddy run my AFR gauge, so im doing the tuning by feal.. which is pretty easy after the milage I put down with the gauge.
The sled runs really good overall, pretty dang snappy, biggest issue I have right now is when i whack the throttle from idle it definately seems to sputter for a second then take off. If i hang the throttle right below engagement and then whack it it still sorta has the same tiny stumble but is better as it has less RPM to cover before boost comes in and heals the tuning issue. ALso, my idle is definately rich as I have to go WOT when starting or it wont go.. and then it sorta burbles a little like it flooded.
SO im wondering if just cleaning up the idle screws from 2 turns to 1.5 might heal this issue?? sorta lean the idle out then prevent the loading up.
I installed new carb boots and my wacky idle went away..
currently letting my buddy run my AFR gauge, so im doing the tuning by feal.. which is pretty easy after the milage I put down with the gauge.
The sled runs really good overall, pretty dang snappy, biggest issue I have right now is when i whack the throttle from idle it definately seems to sputter for a second then take off. If i hang the throttle right below engagement and then whack it it still sorta has the same tiny stumble but is better as it has less RPM to cover before boost comes in and heals the tuning issue. ALso, my idle is definately rich as I have to go WOT when starting or it wont go.. and then it sorta burbles a little like it flooded.
SO im wondering if just cleaning up the idle screws from 2 turns to 1.5 might heal this issue?? sorta lean the idle out then prevent the loading up.
givemeaboost
TY 4 Stroke Junkie
- Joined
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- 03 Rx1 Turbo
- LOCATION
- Great Falls,MT
clean your pilot jets and open the the screws to 2 1/4.
Ski-Dooin' it
Expert
hmm... i leaned em down around 1/2 a turn and seemed to make the bottom a little better.. but are you thinking my bottom is to lean, thinking about it... that would make me need throttle to get it going from idle. I want my afr gauge back!! then i can work accuratly, nothing else is gonna get messed with until then.. otherwise im just chasing my tail.
other then that it runs like a SOB and is pretty snappy as well. isnt super fast out of the hole, but I think thats partly my gearing...
other then that it runs like a SOB and is pretty snappy as well. isnt super fast out of the hole, but I think thats partly my gearing...
