Question
carbs
QUESTION: Hi
I recently purchased a non running 89 gsxr 250. Ive got it running and cleaned the carbs, but the guy who had it before changed the standard ones so the jetting could be done for Pod filters, as he couldnt find a replacement airbox.
Anyhow, Ive managed to get it to idle, but thats about it, it struggles to rev to 6000rpm. I took th filters off while running, and turned the throttle, none of the slides opened, hence i think it flooded itself with not enough air.
Ive attached a pic, i need to find what goes where. I think im correct in that the small black hose coming off the carbs is what connects to the fuel tap vacumn. But the others Im a bit unsure about
thanks
ANSWER: The center hose goes to the fuel tap feed nozzle.
The two hoses coming from between 1/2 and 3/4 are vent
hoses and they route to open under the tank.
Running with pods may be tricky. You can try restricting
the airflow by covering part of the pod or by stuffing something
into the pod.
The problem is not too much fuel, but too much air. The carbs
need a certain amount of restriction to work right. The airbox
is tuned to the carbs and provides restriction and capacitance
and is matched up to the operation of the sliders. Without an
airbox you will never run perfectly but you can still get a working
bike.
---------- FOLLOW-UP ----------
QUESTION: hi
ok can you please help me a bit more.
The top two hoses, where should they route?
The bottom 3 hoses where should they route.
The reason I ask is i saw a pic of almost identical carbs with two fuel hoses to the outer lower pipes.
I ran a test off the bike, the floats in 1 and 2 fill form lef and 3 and 4 from right.,
Nothing then comes out the 3rd middle inlet.
ANSWER: I didn't even notice the two inlets (purple X).
I think your carbs are a bit different than the
older GS carbs. I'm guessing you either have a
petcock with two fuel nozzles or you need to run
a T to feed both sets of carbs. In which case the
middle must be an overflow which you want to route
to the ground (under the bike).
The two hoses marked with an orange X are still
the vent hoses which need to route under the tank
pointing to the rear of the bike and must be left
open. Just route them to a secure spot along the
frame and maybe zip tie them so they don't move.
---------- FOLLOW-UP ----------
QUESTION: thanks alot for your help, its giving me the confidence i need to try and resolve this without resorting to vanning the bike to a mechanic.
if its any help the outer lower two are soft to the touch and squeeze the middle is solid plastic
So is your suggestion still the same.
Would make sense to me as the fuel inlet should be higher than the floats in gravity fed systems? and the overflow bottom?
thanks really alot for replying so quickly , my friend and i scratching our heads about it at the weekend.
AnswerI'm not 100% sure about the overflow since it looks like it sits kinda low. I'm pretty sure about the vent tubes, though. The vacuum hose to the petcock is pretty obvious and the fuel hoses you've already checked out.
One thing you can try is posting a forum message to the tech section at www.thegsresources.com
These's alot of gsx owners there which may know exactly what's what.
