1996 Pilot Jet issue - Sputtering when cracking the throttle

[Wrench 23]

Hey Everyone,

Let me intro myself for this is my very first post.. My name is Rick and have been a fan of BLASTER FORUM for a long time learning countless of info from here thanks to you all.. You guys are great!!

Machine specs:

• 1996 blaster - Im the only owner since new.
• Pro Circuit full exhaust
• Vforce 4 reeds
• Air box lid w/ filtered vent holes
• Uni foam air filter
• 400ex rear shock
• Sedona Bazookas all around w/ 20's in the rear
• 350 Main Jet from Dynojet jet kit
• 32.5 Pilot
• Air screw position - hard to say (see below)
• Stock needle w/ clip in 3rd
• Still run w/ oil injection
• Moose clutch lever w/ terminator cable
• Tusk clutch kit
• ... and other cosmetics

it's well taken care of with constant maintenance performed..Never beat on.

QUESTION
It starts up great. Choke out / 2 kick / starts.. Choke in 1/2 to warm up then choke in for the ride.
Starts great when warm too with no help needed from the choke.
Machine smokes normal for a 2 stoke with no bad burning smell.
Idles great with no hang times. Comes back to idle nicely from quick WOT.
Everything is clean and tight (carb, new plug, air filter)
No leaks..
Powerband is strong throughout 1/4 throttle - WOT..

The issue is at first crack of throttle off idle up to the most 1/4.. It sputters and feels flat / no power. Barley any response. Once you open the throttle a little more, it clears out instantly and snaps with power which is hard to handle since I'm doing mostly trail riding.. At times you need that low low throttle control and not screaming mimi..
This sounds to me that I needed to make pilot circuit / air screw adjustments.
Adjusting the air screw doesn't help. 32.5 pilot jet in. Starting from 11/2 turns out - turning the screw in to find the idle drop (all the way in does make it want to stall but not too bad)..
Idle gradually goes up as the screw is turned out. Turning the screw out to find the idle drop, in this direction, never happens. Once screw reaches 21/2 turns out, the idle is at the highest and continuing to turn out the screw does nothing at all.. It suppose to drop a little, right? I've read on here that if the screw is too far out then you need to lean out the pilot jet.
I dropped a 30 pilot jet in since the screw was so far out (lean) and redid the same adjustments starting at 11/2.. The only difference the 30 made was if you turn the air screw all the way in, it immediately stalls from being too rich which i thought was better than the stock jet that barely made it stall when turned all the way in.. Again turning the screw out to find the second idle drop doesn't happen and anything passed 21/2 turns out is empty meaning nothing happens..

The pilot circuit is telling me that it's still too rich? I cant find the second idle drop when turning it out.
Would lowering the pilot jet even more to say a 27.5 hurt the engine? No matter which pilot (32.5 stock or 30) I can't get rid of the sputtering at first throttle crack off idle to 1/4.. The sputter sounds exactly the same as if you have a too large of a main jet in. You get that too rich, no power, sputter sound / feeling. I can not get it clean and crisp in the low rpms.

Sorry for the long novel.... haha
Thanks for all your time and help!!

 

[Fast6hand]

Your not looking for an idle drop. When adjusting the air screw. Set your idle higher than normal. Start screw at 1 1/2 turns out. Warm up bike. Now start adjusting air screw slightly in each direction until highest idle is achieved. Once that's acheived and your within 1/2-2 1/2 turns out your golden. Now set idle to desired location. Depending on temp/humidity and such, you may need to adjust that air screw on the fly.

 

[Wrench 23]

Hey F6H thanks for responding.. I have started at 1 1/2 w/ bike warmed up.. I've turned in to find the highest idle. Once it starts to go down in idle, i stop and now turn the screw out to find the highest idle in that direction.. The idle does raise higher going past 1 1/2 turns out, but it doesn't respond to anything after reaching 2 - 2 1/2 turn.. Once i reach around here, the idle is the same no matter if I turn it out 3 turns. from say 2 1/2 turns out and on is all the same idle.... It like the screw adjustment does not respond after between 2 - 2 1/2..
I drop a jet size to 30 with the same results and the same sputtering at low rpm (just cracking the throttle to about 1/4)

I was hoping if a 27.5 pilot would do the trick to stop the sputtering and not hurt anything..
Like I was saying before, it sounds the same as if you drop a huge main jet in and get that rich sputtering..

 

[Fast6hand]

That's good it's not responding, that means you highest idle has been achieved. From there you can fine tune it in smaller increments. I would keep the 32.5 pilot, sounds like it's ok. Anywhere between 1/2-2 1/2 turns out at highest idle you good.

 

[Wrench 23]

dude that's great news! I'll do just that..
Any ideas as to what might be the cause/s to the sputter/flat power at the first movement of the throttle to about 1/4? under load of course.. Not under load, it runs great through all the throttle stages.

 

[Fast6hand]

Have you cleaned your air filter in awhile? Checked your reeds? Maybe just a little fine tune on the air screw to find that sweet spot. I like to warm it up. Take a screwdriver with you, and crack it open. If it starts to sputter, try making a slight adjustment on the a/s until it clears up. My bike has always had a slight stutter when first riding, but it always clears up. All blaster are different however.

 

[speedyslyder]

lets see it pics
what 2 stroke oil are you using? just curious

 

[Wrench 23]

That's a good idea.. Getting out there, crack the throttle to where you hear / feel the stutter and then tune the A/S.. I'll do just that and see how it goes..
The reeds are tight, no warping and clean..

 

[Wrench 23]

lets see it pics
what 2 stroke oil are you using? just curious

I'll get pics for sure..
I'm using AMSOIL DOMINATOR injector oil..
What I've noticed thought is that recently it looks as if there is more oil in the carb than usual.. I don't know if it's just me, but when I clean the carb, you see excessive injector oil in the carb.. Could the oil injector be pushing too much oil through? Would that make it sputter at first throttle crack to 1/4?