Topic: Have gas in your air box?

[jkidd01]

So the other day, I noticed that my bike doesn't like to rev higher than about 5k and wouldn't go over 65 MPH. I took it in to my local Honda bike service center and they told me my carbs were just too dirty and needed to be cleaned, and that they could do so for just under $200.

Well, I was just about to take the bike in to have them actually go ahead and clean and sync the carbs for me today, and since the airbox was filling up with gas and basically made the air filter useless, I decided to pull that out and drive it in without one in there. Turns out the problem was being caused by a dirty air filter the whole time.

So the moral of the story is: if you buy a used bike and are told it got "a full tuneup" and an oil change... don't believe them and give it your own tuneup.

[Laminar]

If the airbox is filling with gas, I don't think that a dirty air filter is your only problem...

[brycegp]

Gas in your airbox would mean your carbs are overflowing.  And that is usually caused by stinking floats...and cleaning the carbs should clear that up.

[Gordon]

Gas in your airbox would mean your carbs are overflowing.  And that is usually caused by stinking floats...and cleaning the carbs should clear that up.

Those damn stinking floats!

[brycegp]

STICKING floats...DOH!!

[jkidd01]

Ah, except once I changed out the air filter, there was no longer any gas flowing into the air box at all. I also pulled the carbs, and none of the floats were sticking, and they were clean.

[bzr]

Those damn stinking floats!

Floats? We don't need no stinking floats!

[BobbyR]

As the famous Bob Wessner says "Carbs Suck". It looks like dropping the bowls may be in order.

[brycegp]

my 750 was bleeding fuel from the airbox.  dropped the bowls and there was rust flakes just hangin' out in there.  the floats seemed to move freely but after I clean out the build up...it hasn't happened since.

[Cvillechopper]

Ah, except once I changed out the air filter, there was no longer any gas flowing into the air box at all. I also pulled the carbs, and none of the floats were sticking, and they were clean.

You most likely dislodged what ever it is that was keeping your floats from cutting off the fuel to the bowl.  It is not possible for a clogged air filter to cause fuel to flow backwards into the filter housing.  You have to have 2 problems for this to happen.  The float(s) are not shutting off the fuel like they are supposed to AND the overflow tube(s) are clogged preventing them from draining the extra fuel out the bottom of the bowl. 

[brycegp]

Once mine were sticking just because the hinge wasn't swinging properly.  The carb was shiny clean and still it was overflowing.  Sometimes you need to remove the float arm and get the hinge really clean too.