crf/xr 80 engine help/advice

[my67xr]

ok, so in post #18 above, i have given you 2 things that could cause it to flood/overflow

so take the carby fuel bowl off the bottom of the carb.
with the fuel tap turned on and the hose running to the carb, can you lift the floats and see if the fuel stops flowing?

if it doesn't then you need to bend the centre tab up a touch, this will lower the float level, and turn it off earlier
click on the picture to enlarge it

 

[my67xr]

here is a picture of a different style Keihin carby , but has the same float setting principles.
the bottom of the float should be 21.5mm off the base of the carby with the centre tab touching the tip of the needle
it is spring loaded so measure the float height with the pin( in the needle) touching but not compressed

 

[blkwdw]

wont let me view the attachment. So i bend that centre tab yes?

 

[my67xr]

fixed the picture,
yeah just bend it up a little more to lower the float level (towards the needle/seat)

have you tried measuring it as per Keihins specs ?

 

[blkwdw]

No i havnt yet. Were do i get the specs from google i take it. Will see what i can find

 

[my67xr]

^^ they are in post #22 above

 

[GooseMan]

Did it over flow before you pulled it apart? cause in that case, it may sound silly but maybe you put the float in upside down? it has happened before. If it was overflowing before you pulled it apart then just go ahead an ignore

 

[blkwdw]

Did it over flow before you pulled it apart? cause in that case, it may sound silly but maybe you put the float in upside down? it has happened before. If it was overflowing before you pulled it apart then just go ahead an ignore

No it wasnt but i didnt pull the float out. I got the bike running. Changes gears smoothly and rides good. It still has that squeel though but you can now only hear it at idle. Once your riding or even if your stationary and hold the revs on just a touch it goes away. Not to sure what it could be but even so its not as loud as it was before either.

 

[my67xr]

it could have a vacuum leak ?
start the bike and let it idle.
spray some wd40 on all the joins around the carby to fuel bowl, carby to spacer, spacer to manifold, and manifold to head

if the idle changes in any way then there is the vacuum leak
they can squeal a little sometimes as the air passes through the gap.