full throtle probs

[zman]

I seam to have had the same prob for a while but not always shown up.

this only happens when throttle has been open for a min or two.The bike starts to splutter like its running out of fuel.
does not happen on full tank.Only when it gets to around the point of going on reserve .
Seamed like fuel prob but fuel flow on fuel tank is good.have also changed fuel tap[thanks eddi]
carbs have new jets but could there still be some sort of blockage that only sonic cleaning will solve.

[Mark Tiller]

float heights set wrong?
Vapour lock? drawing fuel fast from the tank causes a vacuum inhibiting the fuel flow
muck in the bottom of the tank?

[Pigford]

I'd go with fuel flow - check tap filter/s & pipes ..... and filler cap vent

[Rich]

Probably is running out of fuel if you are on prolonged full throttle, opening up the fuel galleries in the carbs will help as will fitting a bigger fuel tap. This is the main reason 29mm s/bores are much better than 28mm Mikunis.
To eliminate tank breather out of the equation undo the cap when it is doing it.

[Garn 1]

What about water in fuel it does stay on the bottom!
Start a fresh, empty tank and refill with new petrol.
RegardZ

[Rich]

Just drain the float bowls into a tin and see if there is water in it.

[Pigford]

............... double check coils - connections & +12v supply when running

[andyb1962]

my bike had this problem a year ago.
previous owner fitted a pingel fuel tap from the states. problem solved.

[Al]

I drained the Z1r tank recently through the tap hole several times and found a piece of pliable newspaper the height and diameter of the fuel filter!!!

AL

[zman]

Thanks for all your help.i will work the list till i fined problem.easiest first of course.