bike still wont start

[karl.harris]

Hi guys well i got a zxr 750 for the track and i was told i needed a vaccum pump for it but i found out that its only the us bikes that have that.iv stripped the carbs and gave them a good old clean and a new fuel pump and still nothing.Tryed spraying petrol down the carbs and still nothing.Sounds like its going to start and pops and backfires.Anyone think what can be wrong with it

[karl.harris]

right well iv been cranking it over and i can smell easy start and petrol from when i was was spraying it down from the carbs as i had the airbox off.is this good or bad

[karl.harris]

Morning all well last night i was fiddling with the bike and i saw that only No3 had a good strong spark and that 1 2 4 were weak.would you say the cdi is at fault

[deej]

if no 3 had a good spark have you thought that it may be the other 3 plugs are knackered ?

[karl.harris]

No as there brand new plugs

[deej]

ok,are they set correctly ?
im no mechanic so just trying to help
it might be your ht leads ?

[karl.harris]

yeh they are set up right.im taking the coils etc to my mate when he gets home from hoilday for him to test them as he knows more about bikes then me.cant be the battery as its new to

[karl.harris]

i also put a volt meter across the battery when turning it over and its 21.9v

[Banditmax]

21.9v????????????? thats wayyy too high. 14 is about as high as you want, and when cranking it should drop a bit so 21.9 is nuts. Id be looking at reg/rec problems or maybe alternator problems.

[billinom8s]

do you have a haynes for it?

[karl.harris]

No its only 14.5v at 4000 rpm