Ski-Dooin' it
Expert
So i finally got the yamadoo out today in som real snow to test things out. snow was about 1' of fresh on a 3' base and nice short pretty steep hills to get a nice load on the motor.
If i run WOT from standstill it pulls up to full rpm nicely, sorta slow thought, but as soon as it gets to peak rpm it starts to gurgle and loose rpm.. afr bounces around down by 10... i have almost no power if i peg it wot on the hill and hold it, I get stuck if i try to. If i run say 1/4 throttle or maybe a little more and sorta feather it to keep it nice and clean it runs good and pulls hard... obviously not WOT.. but it runs right along my buddies rev. seems to be loading up on me... would this make sense?
current jetting is 135 mains 17.5 pilots..
seems like I should try some 130 mains out to clean it up? I have a sort of pitot type jet thats a bleeder valve, it helps a little, but not a whole lot,
If i run WOT from standstill it pulls up to full rpm nicely, sorta slow thought, but as soon as it gets to peak rpm it starts to gurgle and loose rpm.. afr bounces around down by 10... i have almost no power if i peg it wot on the hill and hold it, I get stuck if i try to. If i run say 1/4 throttle or maybe a little more and sorta feather it to keep it nice and clean it runs good and pulls hard... obviously not WOT.. but it runs right along my buddies rev. seems to be loading up on me... would this make sense?
current jetting is 135 mains 17.5 pilots..
seems like I should try some 130 mains out to clean it up? I have a sort of pitot type jet thats a bleeder valve, it helps a little, but not a whole lot,
HURRICANE
TY 4 Stroke God
How much boost are you getting?If your mids are also rich,you can drop the needles a clip or to instead of lowering the main jets
Ski-Dooin' it
Expert
when i mash the thing it runs up to my 10# wastegate setting but then starts t odie off. if i ease on it like I said i run around 6-7#... but even then its pretty dang rich and i have to be easy on it as my air fuel is still way low.
I would check for boost leaks, that can play havoc on your tuning.
You need to bleed more air off your line going to your float bowels.
Skydog
Skydog
What do you want to run for boost. If your wastegate is set at 10 and your boost guage is only showing 6 the first thing I would do is stabilze the boost to where you want it. With a headshim 6 lbs is nothing. Changes in boost will affect your jetting to a degree so get that set first then go after the A/F.
Rx1M5
Rx1M5
Ski-Dooin' it
Expert
no, i can hit 10# if i go WOT from idle, the reason its only showing 6 is cuz i cant sustain WOT.. im building 6# at low throttle easing up the hill.
and i tried to bleed off more air, but it started having a negative affect on my bottom end and midrange so it runs really goofy and its honestly not very rideable when the thing acts like it does.
other issue im fighting iwth.. i have my fuel pressure referenced off of my carb boots.. problem is when it gets nice and warmed up it idles way high cuz my pressure drops to 1# cuz of super high vaccum, so then i turned up my fuel pressure a little bit to try and deal with this but now im wondering if i have to much fuel pressure?? i have 4.5# of pressure when i sit and run my fuel pump with the sled off. but this is when it goes down to low at idle.. then i get a really high lean idle when its gets warmed up;.
and i tried to bleed off more air, but it started having a negative affect on my bottom end and midrange so it runs really goofy and its honestly not very rideable when the thing acts like it does.
other issue im fighting iwth.. i have my fuel pressure referenced off of my carb boots.. problem is when it gets nice and warmed up it idles way high cuz my pressure drops to 1# cuz of super high vaccum, so then i turned up my fuel pressure a little bit to try and deal with this but now im wondering if i have to much fuel pressure?? i have 4.5# of pressure when i sit and run my fuel pump with the sled off. but this is when it goes down to low at idle.. then i get a really high lean idle when its gets warmed up;.
dirk_03
Expert
lean it out
Just talked to a buddy of mine from utah that had a turbo rx1. he said it would work best to get the jets right with the jet closed(or a small jet open slightly open in your case) in the pitot at the lowest altitude you ride and you can lean it out from there as you go up in altutude. This worked for him. It sounds like our to rich yet. put 130's in it and give it a try. get that afr to 11.5.
Just talked to a buddy of mine from utah that had a turbo rx1. he said it would work best to get the jets right with the jet closed(or a small jet open slightly open in your case) in the pitot at the lowest altitude you ride and you can lean it out from there as you go up in altutude. This worked for him. It sounds like our to rich yet. put 130's in it and give it a try. get that afr to 11.5.
Ski-Dooin' it
Expert
yeah.. i didnt mind the idea of having the pitot jet pretty far opened.. the problem was.. that was getting it to even sorta run at the lowest i ride and was still way rich...
i want to have my fine tuning done by my bleeder valve, just right now im so far out on my mains i think its a lost cause. it can only do so much before its an issue with other parts of the system.
I did pick up some 130's// got some class here soon like, but then i have a chance to swap em.. take a pull down the alley, then take em to the hills tommorow.
i want to have my fine tuning done by my bleeder valve, just right now im so far out on my mains i think its a lost cause. it can only do so much before its an issue with other parts of the system.
I did pick up some 130's// got some class here soon like, but then i have a chance to swap em.. take a pull down the alley, then take em to the hills tommorow.
130s are going to be to small been there done that, not the mains, its to high of bowel psi and the slides rasing to fast.
Later Skydog
Later Skydog
Idle air screws out some and bigger pilots too... Boy this brings me back hahaha
kinger
VIP Member
Skydog - he is at elevation he may be able to get by with 130's.
4 psi at idle and 14 psi at WOT 10lbs of boost if your using a 1:1 FPR
This is fun that with all the mods you made, transplanting the engine in that chassis and all yoru doing is fighting the tuning, that is pretty good, i was expecting horrendus vibration, parts breaking, etc.
Nice job.
4 psi at idle and 14 psi at WOT 10lbs of boost if your using a 1:1 FPR
This is fun that with all the mods you made, transplanting the engine in that chassis and all yoru doing is fighting the tuning, that is pretty good, i was expecting horrendus vibration, parts breaking, etc.
Nice job.
Ski-Dooin' it
Expert
thanks.. trust me.. i was waiting for full boost to come on and the motor to go flying out the side.. steel motor mounts rock! the motor barely moves at all under load, still thinking of making a torque arm type deal if belts start blowing up.. but only time will tell. it has worked really well putting it in.. just figuring out my own turbo system that isnt a copy of anyone elses is FUN!
skydog- i dont think slides opening to fast is the issue as i cant ease any farther into it then just mashing on it.. so leads me to beleive that its just to much fuel.. if my system doesnt flow all that great then it doesnt need huge jets.. i have bled off a LOT of pressure from the bowls.. when my bleeder is all the way open its like a 1000 main jet in there.. and i have it cranked, all that happens is i get a super lean spot when boost comes on then it loads up as the slides start opening
got some 130s that need to go in.. just kinda cold out
skydog- i dont think slides opening to fast is the issue as i cant ease any farther into it then just mashing on it.. so leads me to beleive that its just to much fuel.. if my system doesnt flow all that great then it doesnt need huge jets.. i have bled off a LOT of pressure from the bowls.. when my bleeder is all the way open its like a 1000 main jet in there.. and i have it cranked, all that happens is i get a super lean spot when boost comes on then it loads up as the slides start opening
got some 130s that need to go in.. just kinda cold out
rxrider
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Do you have your fuel pressure regulator connected to the carb boots?
If so you will have way too high fuel pressure under boost. If you have 4.5 lbs under vacuum at idle your fuel pressure will sky rocket when boost comes on.
If so you will have way too high fuel pressure under boost. If you have 4.5 lbs under vacuum at idle your fuel pressure will sky rocket when boost comes on.
Ski-Dooin' it
Expert
no, i have it set to 4.5# with no vaccum.. i have a switch wired in to prime my pump and warm up my afr sender so i can push it and not just dry crank when i changed jets and emtied float bowls.
i just threw my 130's in.. ill see how she does tommorow! I also remote mounted my bleeder valve by my handlebars, this way i can click it around without getting off or opening the hood. just twist and tune.
I also noticed that sometimes the sled would randomly just die on my and lean pop and have 0 power.. then when i looked at my float bowl line it was developing a kink and would randomly flex enough to stop fuel on boost.. only happened on the way out.. so thinking it just needed a new section of tubing. oh the silly stuff.
i just threw my 130's in.. ill see how she does tommorow! I also remote mounted my bleeder valve by my handlebars, this way i can click it around without getting off or opening the hood. just twist and tune.
I also noticed that sometimes the sled would randomly just die on my and lean pop and have 0 power.. then when i looked at my float bowl line it was developing a kink and would randomly flex enough to stop fuel on boost.. only happened on the way out.. so thinking it just needed a new section of tubing. oh the silly stuff.
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