Bike bogs down and dies

[Thrillwill352]

So I rejetted my bike after I got a new exhaust and k&n lunchbox air filter, new pilots 150 mains and two washers. The bike idles great and starts right up but for every gear I shift up i lose tons of power and it bogs down, I already checked every where for vacuum leaks with wd40 and I believe it's running rich because choke makes it run worse, I tried taking the washers off thinking it was giving too much fuel but still no change. I also check the float heights and they seem to be at the right level. Another thing that I don't understand is it will only run for maybe 10 min and won't start back up unless I jump it and it starts up immediately. Also the previous owner stored the gas tank upside down for a week and it started leaking through the top could it be preventing it from creating the proper vacuum? And I just replaced the inline fuel filter. Also brand new spark plugs. Im going to check the float needle seat o-riling when I get the chance but could the jets just be too big? I'm also going to check the carb vent hose to ensure proper ventilation. Sorry for how long this is I just figured the more detailed the better chance of someone knowing what and where the problem could be. Thanks! -Will

[Thrillwill352]

Any suggestions? I fear i might have to take her too the shop which would cost me just as much as the bike :/

[bombsquad83]

Fuel filters don't play well with our bikes, so it could be fuel starvation due to that.  Also, the tank vent could be plugged due to the gas getting in there are gumming things up.  If the problem is solved when you open the gas cap, then that's your problem.  It wouldn't hurt to clean it out anyway.  There is a good thread with instruction if you search.

However, I'm betting on your needle valves not stopping the gas flow.  Measured float heights don't matter if the float needle valves or o-rings don't seal.  The gas will slowly (or sometimes quickly) overfill the bowl, and the mixture will be way too rich.  The way to check this is by putting the petcock on prime, and attach a clear tube to a carb drain.  If the gas fills the tube when held up in a U shape above the level of the float bowl gasket, then your needles are not sealing.  It might happen slowly, so take your time, and check both carbs.  Gas dripping into the airbox or out of the lunchbox filter are also a dead giveaway of this problem.  If you can't get the gas level correct by adjusting the tab on the floats, then you will need to replace your needle valve sets.  I recommend OEM instead of K&L.  Unfortunately, they will run you about $45 each plus shipping from an online dealer.

Once you solve the above issues.  Then and only then can you judge if the jetting is correct or not.  Since the jetting matrix is pretty well tested, I think it's likely you have other issues.

[Thrillwill352]

Thanks man! Yea I've heard the inline filters aren't the greatest but I was worried about debris getting in the carbs. I will have to check that when I get the chance it seems very probable they could have corroded from carb cleaner. Thanks a ton though! I'll update this once I check

[Thrillwill352]

Installed carb rebuild kit and still experiencing these symptoms, started up great rev'd up good but as soon as I hit 2nd gear it started bogging down, 1000 ft later it sputtered out and died. Any suggestions I'm not sure what could be causing this

[bombsquad83]

Did you check the gas level in the bowls with a clear tube?

[Thrillwill352]

I can try it again to make sure

[bombsquad83]

Just make sure the petcock is on prime when you test it (and then turn it back to "on" when you are done).

[Thrillwill352]

So the valve seats weren't in properly but once I got them seated right the bike starts up every and doesn't die it just doesn't have top end power, it's hard to get to 50mph

[bombsquad83]

You have probably improved, but not fixed the issue completely.  Take a good look at the orings on the seats and replace them if they are at all questionable.  If that doesn't fix it, then you need probably just need to bite the bullet and buy new needle valve sets.

Remember when you do the clear tube test that you need to wait a while to get a good reading.  If the gas level goes at all above the level of the float bowl gasket, even if it's slowly over the course of a few minutes, you still have issues.

Also, what size are the main jets that you see in your carbs, and what air filter are you using?

[Thrillwill352]

The orings are good I just put in a carb rebuild kit which came with valve needle seats and needles, 150 mains, k&n lunchbox and after market exhaust

[bombsquad83]

You still haven't answered whether you have actually tested the gas level in the bowls with a clear tube or not.

Also, were the 150 jets genuine mikuni jets?  Other jets may not use the same numbering system.  You can tell genuine mikuni by the following symbol stamped on the jet...

[The Buddha]

Yes fuel level check ...

And you are rich, and not just rich a little bit. You're straight up drowning in the fuel. Check float level etc.

Cool.
Buddha.

[Thrillwill352]

I checked the float levels and they were right at the gasket level and I waited a while to see if they would rise and they didn't, the bike runs better but still very sluggish and yes I believe they are genuine I got them from Buddha 

[Thrillwill352]

If the carbs suck up some k&n air filter oil could that cause power loss?

[Thrillwill352]

So I got a brand new petcock and removed the inline fuel filter and tried running the the bike with and without the air filter on and still way too rich

[Thrillwill352]

Also here are the spark plugs

[bombsquad83]

The carb on the side of the left plug is flooding with gas.

What do I have to do to convince people that the K&L needle valves suck?

[Thrillwill352]

If the floats and needles are good how do i fix this or what should I check?

[bombsquad83]

OEM are good. You can buy them from any dealer, or any online dealer.

Rockymountainatvmc.com <- they have them in stock for $43
Ronayers.com

Just two possible places...there are many others.  I'll find the part number for you.   

EDIT:  part number 13370-02D00.  On rockymountainatvmc.com, navigate to OEM parts and your bike year and model. Then look at carburetor, and it's part 33 in the fiche.