re: kz750 ltd h2 - primary main jet question

hi kzr's

greetings from across the pond!
my bike is a us version and i live in the uk.
i've just changed the exhaust from a motad
4-1, to motad 4-2. motad advised me that
rejetting is not necessary.
the keihin cv34's have been pro cleaned.
new o rings etc.
i checked all the jets i can find against
the oem manual. the pri main jet is #70's and
not #62's it ran with #70's a bit rich.
my friends sent me some #62's and i replace the
#70's.

the tank liner por-15 failed
and the tank was pro cleaned
out and sureseal 2 pack used.
left to 'cure' for two weeks.

put carbs and tank back on.
battery fully charged.
bike turns over, metal sound.
the bike didn't make this noise at all.

carbs
main jets now wrong ones?

q) #62's are for bikes in the usa.
i've a usa bike in cold, wet uk.
what size pri main jets is recommended
please?

q) i couldn't find the air screw with the
second main jets in. is this sealed off?

many thanks gang!

angel

As far as I know temperature shouldn't have any real effect on jetting. As long as you're near sea level, I'd think the jetting should be fine. If you're at high altitude, it may need changing.

hi del

thank you so much for your reply.

when i bought the bike, the carbs had
#70 main jets. i researched the oem manual
and this advised #62. my friend had 4 new
62's and i put them in today.
when my bike was running, it ran rich.
this was checked/adjusted by the garage.
changing back to oem 62's is realligning
the bike back to factory settings, better maybe?

i was also advised that your emission laws
are stricter than the uk.

q) is #62 the best pri main jet, the best
for the setup?

q2) i couldn't find the hidden second main
jet? is this plugged off, why?

many thanks again!

angel
uk

I think your carbs are the same as mine - Keihin CV34

Stock primary main is 62. A previous owner might have put in 70s if running pod air filters. If you have an airbox then 62 is best.
The secondary main stock is 125 I think. Maybe 120 . Cant remember exactly. In the picture above the seconday main is the one labelled 135. I was experimenting. I have a 4 into one exhaust and a airbox now and have 62 and 130.
Underneath the plastic plug you will find the pilot jet. I think its a 35 but dont worry about it as you cant get replacements and changing the size really does not make a difference.
The only item which may be hidden on a US bike it the air mix screw. Look down on the carb and at the top just to the front of the chrome carb top there will either be a screw head or this will be covered by a metal disc/plug

hi jr

thanks for taking time to photograph
your carbs. they're the same as mine.

i've examined the carbs carefully.
i can find most jets, except the air jet.
not the air/mixture screw. on the cv34
the air/mixture screw is located on the
top/rear of the carbs, behind the chromed
tops.
if you've the oem/other manual.
look at the carb jets table. there are two
main jets. i've cleaned out the #62's jets and
the one it screws into. also the #35 needle jets.
what i can't find is the air screw, this has three
jets in it. i see it anywhere.

i think my carbs has something blocked
in it somewhere. the carbs look sqeaky
clean. i don't have compressed air.
i've had the carbs pro cleaned.

the gas i used was from a month ago.
i'd a gas can and filled it.
does gas go off?

many thanks jr!

nice bike!

regards

angel

The above are taken from Kawasak.com owner info, part diagrams etc
#6 the needle slides up and down through
#7 the needle jet. This is brass and is pressed in. it does not come out
#8 is underneath # 9 and when you remove #9 the secondary main jet (stock 120) it will either fall out or can be screwed out.
#10 is a nozzel and is underneath #11 the Primary main jet (stock 62) and will eiter fall out or can be screwed out when you remove #11
#12 the pilot jet is underneath #13 the polyester cap.
I hope this helps

KZr FILEBASE article:

www.kzrider.com/filebase/doc_download/47...-shop-manual-via-omr

Good Fortune!