Jet needle

[steve bowdler]

Had a little problem ! carb would not shut off when throttle released suspected cables but on removing cables carbs still sticking.
Removed carbs off bike and cleaned , noticed some crud on one of needle vales now the question how robust are these needles , will the tolerate a good scrub or best replaced ?

[Taffus]

send the bits to me and I will lean it in my ultrasonic cleaner

[Pigford]

Needles are quite tough - unless you bend the buggers...... unlike the brass Neddle Jets that wear faster

[steve bowdler]

OK problem sort of back ! replaced throttle cables new carb to airbox rubbers , carbs snap shut with engine off soon as engine running blip throttle and carbs will not shut off any ideas please ?? Standard 26mm carbs on Z1000

[Taffus]

I think you need an alligator sandwich... that's definitely snappy

[floydsz1]

I'm getting simular probs with mine. Starts up and ticks over/revs fine but when it gets hot the revs take a while to drop back to tickover, sometimes staying at 3000rpm, Ive fitted new inlet rubbers (so no air leaks) and new jets/needles etc have been fitted.
Was thinking maybe its the float heights. All cables etc are free etc.
Might be worth sending my carbs away to someone for cleaning and setting up,
any ideas anyone.
ta very much.

[Taffus]

had the same on my GPz 1100 carb conversion and yes, it it was float heights. somehow I had added a 1mm to the height from the carb base to the floats (carbs inverted) corrected this and the hang was gone....

[steve bowdler]

OK will check float heights today , it is a start !

[steve bowdler]

Come on all you carb guru's any more ideas ??

[KeithZ1R]

Probably too obvious Steve but have you checked all the slides are at the same height when shut ? only pointing this out cos I had mine off and apart recently but didnt check em before I put em back, same symptoms as your goodself when i checked one of em was a good half mil+ higher when shut some small adjustment from the top so they all had the 2mm gap (on mine) at the inlet throat cut out problem solved

[njwmct]

Steve, had the same problem on my Mark 2 - turned out to be unequal slide heights.
As a 1st step I set the gap at the bottom of each slide with a 0.7mm dia. wire - then balanced up the carbs with vacuum gauges & the problem was solved.

[z1aphil]

I don't know if these couple of sites may be of help.
Good luck.

Phil

http://www.mikuni.com/pdf/vmmanual.pdf
http://www.iwt.com.au/mikunicarb.htm

[DogsbolloxofZ1B]

Steve,
Give me a call. 07515 367071

Cheers Mike

[Pigford]

had the same on my GPz 1100 carb conversion and yes, it it was float heights. somehow I had added a 1mm to the height from the carb base to the floats (carbs inverted) corrected this and the hang was gone....

Interesting - but I'm surprised that made any difference - especially as it would lean the mix out slightly

[tricky]

hi, carbs will need to be mechanicaly balanced, there is an important measurement between the throttle cable quadrant and the cable guide, this must be correct first, then mechanicaly balance the carbs as per manual, then once back on the bike, check balance with vaccume gauges if you want
hope this helps tricky.