Sputtering!!!!&hissing ???

[NASTYBLASTY]

HI, EVERYONE I HAVE POSTED MY PROBLEMS ON HERE A COUPLE OF TIMES & EVERYONE HAS BEEN SO HELPFUL I JUST WANTED 2 START OFF SAYIN THANX 2 EVERYONE !!! OK SO 4 ABOUT SIX MONTH I WOULD SAY... IVE HAD AN FMF HEAD PIPE & POWER CORE 2 & EVERYTHING WAS FINE UNTIL RECENTLY IT STARTED SPUDDERING & HISSING & i WASN'T SURE IF THE PREVIOUS OWNER HAD RE JETTED IT..

SO MY 1ST QUESTION IS WHAT IS THE STOCK SIZE IDLE & MAIN JET SIZE ?
A COUPLE OF PPL TOLD ME 2 GET THE DYNO JETY KIT ???? OTHER SAID JUST BUY A JET... THEY SAID SOMEWHERE BETWEEN 260 &290 ?? IS THAT 4 WHICH JET, THE IDLE OR MAIN? IS A 300 2 BIG 4 AN IDLE JET ???? SORRY JUS LEARNING !!! ALSO I WAS TOLD 2 CHECK IF ITS RUNNIN 2 RICH & THE PLUG WAS A LIL DARK BUT THE PORCLINE PART WAS A CHOCOLATE COLOUR SO ??? ANYWAYS & NOW MOST OF THE TIME IT WILL NOT START BUT AFTER LIKE 30 OR MORE KICKS IT WILL IF IM LUCKEY BUT THEN WHEN IT DOES ABOUT HALF THROTTLE IT WILL SPUDDER
WILL LIFTING MY NEEDLE ON MY CARB HELP ??? IF SO HOW MANY NOTCHES?

BASICALLY IM JUST WONDERING IF ANYONE ELSE HAS EXPERIENCED THIS PROBLEM, I DID CHANGE MY BIG JET (I THINK ITS THE MAIN JET) FROM A 230 THAT WAS IN THERE TO A 290 AND IT DID AT FIRST SEEM TO FIX MY PROBLEM A LITTLE, BUT AFTER 10 MIN AND GETTING IT TO HALF AND FULL THROTTLE ITS NOT RIDABLE. SO MAYBE ITS NOT EVEN A JET ISSUE?
ANY SUGGESTIONS OR
ADVISE ON WHAT TO DO NEXT WOULD BE AWESOME~!

THANKSSS

 

[Awk08]

if this is a stock carb, 260-290 are the main jet, and the stock 32.5 pilot will be fine for your mods

as for the rough running and hard starting
i'd suggest a compression and leakdown test, before you cause any further damage

 

[Blaaster]

Stock pilot is a 32.5 a is ok for you.

The main should be in the vicinity of a #270 or bigger.

Leave the needle in the centre clip.

As Awk posted " i'd suggest a compression and leakdown test, before you cause any further damage."

Read up on plug chops and do one !

 

[NASTYBLASTY]

Thanx guys ill give these couple things a try !! Also is it possible that i have damaged my topend by having a smaller get in it with the fmf exhaust?

 

[Awk08]

here, lemme help you with those things....................

http://www.blasterforum.com/engine-13/compression-test-how-many-kicks-14485/

http://www.blasterforum.com/do-yourself-20/how-plug-chop-38674/

http://www.blasterforum.com/do-yourself-20/build-use-leakdown-tester-10663/

slickerthanyou on here makes and sales them very reasonable,,,,,,,,,,,,,,,
http://www.blasterforum.com/do-yourself-20/videos-how-perform-air-leakdown-test-31464/

 

[NASTYBLASTY]

I meant smaller jet !!!

 

[Awk08]

I meant smaller jet !!!

you mean when you were running the 230, yes that could have caused damage

the compression and leakdown tests will tell you whats going on in there

 

[pwgsx]

if the jets are fine, check the Stator.....I had a very similar problem on my dirtbike, turned out the stator was bad. IT was hella hard to start and when it ran it was boggy. I thought it was the carb, it wasnt, replaced the coil, no change, replaced the stator with a Moose brand, still bad, then found out the Mosse stators suck. Got one from Ricky Stator and worked like a charm. Good luck on your findings

 

[gottaroost]

Definitely want to verify your jetting to make sure damage not coming from that. I would also make sure the fuel is very fresh, as in no more than 3 weeks old---these fuels do not last very long before breaking down. My dirt bike will not start or run for squat if I do not clean out the fuel from the tank AND the float bowl. Lastly put in a new plug (not a cleaned off plug but a brand new one).

 

[Larry's Shee]

Also as it gets colder you need to jet larger. If it was lean (stock jet) before, you will be super lean now. When you have carb apart write down jet sizes. Listing all your mods will help us.

 

[NASTYBLASTY]

I:I

you mean when you were running the 230, yes that could have caused damage

the compression and leakdown tests will tell you whats going on in there

ok guys thanx 4 all ur help i finally got done 2 it & took it all a part & all the stuff came in the mail yesterday *i got super stock carbon fiber boyseen reeds & a bunch of mukini jets so i went with a 35 piolet jet & a 250main with those reeds & a new plug & she fired up in 2 kickz i had a smile from ear 2 ear hearing that twang sound i fell back in love with her lol!!!! thanx again 4 all ur help i got a blaster freak sticker 2 puton it cant wait !!!I:IB)B)

 

[Blaaster]

I must admit that i am a little concerned, FMF, wintertime and a #250 main with a #35 pilot does just not gell with me.

I feel that you are a little lean, please do a plug chop before you ride again.

I would start at #270 main and a #32.5 pilot , making sure that the carb is perfectly clean.

If you need a #35 pilot in a stock carb, something is amiss, because only heavily modded ang BBK motors need a pilot change.

 

[brandoz28]

I agree. You really Should be OK with the 32.5 pilot. Is the airbox lid still on it? If so 250 may be OK but do a plug chop to verify

 

[blasterdemon7]

It seems no one is addressing the hissing sound. Could that be from a badly leaking head gasket?

 

[xKroniK13x]

It seems no one is addressing the hissing sound. Could that be from a badly leaking head gasket?

Good call bro... no one did say anything about that. I never heard of jetting causing hissing...

 

[Blaaster]

Could te sputtering be caused for running too lean.

Could the hissing be caused by an overheated motor, stretching the head bolts on cool down, causing the head gasket to leak.

How is the compression?

 

[BlasterIan]

I had this problem with my Blaster when I had the FMF full system on. I stay in Cape Town, South Africa and in summer I temp is on average 28C - 38C.

The only thing that sorted out my spuddering etc was by removing the airbox lid and re-jetted the main to 290, with the Air/fuel screw out 1.6 - 1.7 turns out.

Immediately the problem went away.

The pilot was stock and the needle was in the middle clip.