should the pilot jet - looks like the one in piccy below - be drilled all the way through?

as far as I can see, there is a hollow tube after the threaded bit with 4 holes drilled into the side (on left in piccy) but no hole all the way through (seems to me they are not drilled).... but the slot in the base has a blind hole quite a few mm deep.





[Edited on 5/10/09 by 02GF74]

They should have a hole all the way through, but the hole is very small.

On my old yam 750 they got bunged up after it had stood for a few years and were quite hard to clear. Very fine stiff wire might do it. Otherwise soak in carb cleaner and blow them through.


Stu

ta.

yep - that makes sense ... and explains a lot of things.

It makes sense it goes all the way through since a) that is how the fuel would go - the holes in the side are for air mixing plus b) why bother drilling a blind hole??

been trying to poke a wire but although I am sure it is less than 0.5 mm, that still is too big. (0.2 mm is the word)

Try a bristle from a wire brush but if it's a new jet it shouldn't need clearing. The holes for the side are like the ones in an emulsion tube. Are the jets Mikuni ?

yes mikuni.

33 years old but bike, low mileage, has been standing the last 10 years - carbs are spotless inside.

yey - a strand from some mountain bike gear cable done the trick.

runs much much much better..... still a couple of probs - need to figure out why the cold start is jamming against something plus one needle valve is leaking - seems ot be different one each time I take the carbs arpart