Please help w/ my 300

[ridered300]

I have a 99 300ex. Ive never had any problems at all. But recently it has started "bogging" down in all the gears. 3rd is the worst, 5th is te best, but it is noticeable all the time. It feels like it isnt getting enough gas.
1st I checked the smoke color, it looked a tannish brown, how its supposed to be.

Then I checked the Spark Plug, same for it, tannish brown, if anything kinda dark.

A friend said to drain the carb, rev it a few times, and then close it back up. I did that as well and it didnt work.

Somebody mentioned setting my idle speed higher, tried that, helped a little but didnt fix it by any means.

Im out of ideas, I know this post is lengthy but please help. Thanks

[ATV_MAN]

I dont know if it is the same thing that happened to mine but i was riding all day and i was bogging in every gear.Checked everything but then i looked at last i was riding with the choke on all day.Im a idiot lol. Check and see if you have your choke turned on.

[redryder300]

I did the same thing. Rode for about an hour with the choke engaged. I was about to take the carb off and check my jetting when I noticed my choke lever was all the way forward.


Have you done any mods lately ??? New pipe or taken the airbox lid off?? Give us some more details.

i rode around with my gas line kinked and thought i had a problem LOL. i also sometiems forget to turn the gas on.

[yamaha1470]

first check for little things liek is there gas? is the choke on? is the gas turned on? cuz its probably something small if it just started out of nowhere. maybe u should check ur airfilter?

[ridered300]

Gas is on, choke is off. No recent mods. I'll check the gas line but I dont think that is it either. I have a stock pipe, airbox lid on w/ vents. K&N air filter w/ a prefilter. Keep the suggestions coming! Thanks

[redryder300]

Does it bog at 1/4 throttle, half throttle, 3/4 throttle or full throttle???
How old is the gas in the tank? Have you cleaned the fuel filter screen in the tank??
Have you checked the airfilter?
Have you checked the prefilter to see if it's dirty?
Did you pull a wheelie and pack the tailpipe with mud??
Did you go thru a creek and fill the airbox with dirty water??
The list goes on and on.........

[own2424]

It could be the Jetting.
Clean the Filter.
Could be teh FLOAT in the carb.
Maybe the gas line.
-Same thing happened to me, and i brought it to the shop after i TRIED EVERYTHING and they said one of teh jets fell out and teh float was messed up.
Good Luck!

[ridered300]

It usually is 1/4 and 1/2 throttle.
The gas is new, maybe been in there a week
Im not sure about the fuel filter screen in the tank. I've never heard mention of it.
The airfilter is fine, the prefilter is fine, tailpipes clear and the airbox is dry. Other than those things u mentioned Im not sure. Tell me a little more about the fuel filter screen.
Thanks

[redryder300]

The fuel filter screen and strainer are attached to the gas petcock.
Remove your fuel tank, drain all the gas out of it.
Unscrew the nut from the bottom of the petcock and you'll see the strainer screen..it's flat and about the size of a quarter.
Now unscrew the petcock from the fuel tank and pull it out of the tank and you will see the fuel tap filter which is about 2" long and about as big around as a pencil.
Remove both of these strainers and clean with solvent, also clean out the inside of your fuel tank and the petcock while everything is apart.
I doubt that this is causing your problem but if you have any rust or trash in the tank, then they may be kinda clogged up and reducing the fuel flow.

Your problem really sounds like a needle jet issue. Is the bike running ok from half throttle to full throttle?

["BLAHH"300!!]

ran with my gas on off, it started running out of gas
so i put it, (thought i put it,) on reserve, got down the road and ran out, it was about 2:00 in the morning, looong night for me....

ran with my choke on, had to get on the internet and pm LRD416EX he told me to drain the carb, did that, ran it again, still messing up, while i was running it, i just happend to think, choke...flipped it and she woke on up, i forgot i flipped the choke when i was putting in my blue lights...

ran it with a clogged breather hose, freind though a funny thing would be to shuve a stick in the hose that come's out of my tank lid...haha.real funny..i was pretty hot before he showed me what the problem was....

little things....