backfiring when letting off the throttle

[PismoGuy400]

do i need to richen the carb?

i am running a 146 main (what dynojet roccomended)

my only engine mod is a T-4 slip on.

pro circuit said go w/ a 155 which should i do?.. i am not familiar w/ jetting so i guess i better start learning

BTW the person that WOULD and SHOULD be here to help me with this is no longer here so my next choice is to come to all my fellow EXriders

[lilpoppy]

pull out your spark plug and if it is black it is too rich if it is white you are too lean. You want it a light brown color. Look at the inside of the plug for the color on the porcelain part.

[300exazzkikr]

Check for an exhaust leak where the silencer and the header pipe meet. If there is a leak then that could be your reason of back fire. Sometimes the connection isn't tight enough and even the slightest air that gets through will cause backfire. I always put some High temp silicone gasket sealer on mine and it makes leak free fit.

[PismoGuy400]

i will check the plug tomorrow, and just in case i will also tighten the bolts to the silencer... but i doubt that's it.

any more suggestions guys?

thanks in advance
pismo

[AtvMxRider]

Originally posted by 300exazzkikr
Check for an exhaust leak where the silencer and the header pipe meet. If there is a leak then that could be your reason of back fire. Sometimes the connection isn't tight enough and even the slightest air that gets through will cause backfire. I always put some High temp silicone gasket sealer on mine and it makes leak free fit.

What he said!:D

[OutlawEX]

It can also be the gas u are running in it...The same thing happens in nascar thats y u see their cars spit out flames because they gas is bad

[JOEX]

I may be way off base here....could it a lack of intake air? You may want to get an aftermarket air filter.

Joe

[BKVIEW4U]

i have a t4 also. as ive said alot before. get a 42 pilot jet , it works wonders for the back firing on decel . and the 146 main should be fine if have have absolutely no other mods. i have a 160 in mine. stock piston . stock cam. just a k&n and massive air box mods . so if u do airbox or filter u should b ok

[PismoGuy400]

BTW if it matters my riding elevations range from 0 to about 1000 feet

75% of the time its between 800 and 1000 feet...

, and i forgot to mention i have a prefilter on the stock air filter

outlaw.. its not the gas

if it is the air intake, should i drill a few holes in the airbox?

what should the fuel mixtire screw be set at?

thanks again..

[bmw500hp]

If you get into the carb you might try needle clip position...you have to to watch becuase this might lead to a loss in throttle response....I am running a 152 main in mine and it pops but runs very strong.

[kicken250x]

Hey PismoGuy400, CKY stands for CAMP kill your self not CAN'T kill your self.....and yes they are the greatest punk band of all time!!