2005 YZ450F Keeps cutting out on me. help please

Last summer my bike was running good and then I had a bad crash and had to have surgery. I notice now when my bike is running it likes to cut out on me easily. Was wondering if anybody has had this problem or could point me in the right direction. I took my carb off and clean it which did help the bike start easier, but it still likes to cut out on me a lot.

did you ever drain the old gas out of the tank?

The gas thats in there is about 4 months old.

The gas thats in there is about 4 months old.
Start with that.

Ok I will, what would you suggest if I still keeps cutting out on me?

Ok I will, what would you suggest if I still keeps cutting out on me?

by running that old gas you basically fouled the carb up again. sediments can settle to the bottom of the tank after sitting that long so flush the tank a couple times with clean gas before hooking it back up to the bike. Cali gas goes bad really fast from all the additives they put in it. especially when stored in a plastic gas tank that breaths.

where in the RPM range does it cut out. what are you doing when it cuts out?

Change gas, clean out all jets and etc in the carb (if you can figure out where in the RPM range it is cutting out you can narrow down what jet is not letting fuel past). check float bowl make sure it's not getting stuck.

then report back.

by running that old gas you basically fouled the carb up again. sediments can settle to the bottom of the tank after sitting that long so flush the tank a couple times with clean gas before hooking it back up to the bike. Cali gas goes bad really fast from all the additives they put in it. especially when stored in a plastic gas tank that breaths.

where in the RPM range does it cut out. what are you doing when it cuts out?

Change gas, clean out all jets and etc in the carb (if you can figure out where in the RPM range it is cutting out you can narrow down what jet is not letting fuel past). check float bowl make sure it's not getting stuck.

then report back.

It varies. Sometime just after I start the bike and let it idle for a a couple minutes. yesterday I rode it up the street and when I slowed down to pull in my garage it cut out. I would say mostly at low idles and when I rev it. I will try what suggested and see if that helps. Thanks

is your fuel screw set to 2.5 turns out?

this is a low end idle problem so check your fuel screw first.

if it is, try turning it out to 3.5 turns and see if the problem is solved. if so you will have to adjust your pilot jet a size up and return your fuel screw to 2.5 turns.

if you turn it back in to 1.5 turns and it solves the problem you will have go down a size in your pilot jet.

if the fuel screw remains with then 1.6 - 3.4 turn range there is no need to adjust the jets.

it's also hotter out now then it was 4 months ago so this will affect your jetting a bit.

I recently got an 06 yz450 and it does the same. Anyways your saying this is causes by the pilot jet being to lean. makes sense

i recently purchased a very clean, low hour 04 that sat for pretty much 2-3 years. it would do the same thing. pull the carb and clean the pilot jet out (or replace it). it sounds like your idle circuit is lean and this is a easy and likely place to start

Yeah that sounds about right. I'll figure I will start with cleaning carb, pilot jet, flush the old gas out and go from there and see what happens.

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