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Carb to much fuel

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jez1100r
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Carb to much fuel

#1 PostAuthor: jez1100r » Tue Sep 29, 2015 8:22 am

I was running a Harris with competition baffle .now have a marshal deep tone .bike is not starting well . And a flat spot between 2500 rpm and 3500 rpm .have fitted hotter plugs plugs still very black and droped needle one groove . Think it's time to rejet any body know best size to try. Also has v& h filters Kawasaki z1100r

jez1100r
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#2 PostAuthor: jez1100r » Tue Sep 29, 2015 8:45 am

Also air jets out 3.5 turns

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Pigford
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#3 PostAuthor: Pigford » Tue Sep 29, 2015 1:55 pm

jez1100r wrote:Also air jets out 3.5 turns


Once you get the air screws out to about 4+ turns, you really have to think about going down a size on the pilot jets. Do this first, then re-try running/plug checks, etc, before changing main jets or needle height.
And on the 7th day... Zeds were created!

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#4 PostAuthor: jez1100r » Tue Sep 29, 2015 5:31 pm

has 37.5 standard pilot jets in .but 1575 On 1+4 and 160 on 2+3 .The needle is a 5 b c 6 .which is whey i thought to reduce the size in main jets

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#5 PostAuthor: jez1100r » Fri Oct 23, 2015 3:01 pm

Droped pilot jet to 35. From 37.5 ,air jets now at 2.25 turns out . Starts better .still have flat spot at 2500 rpm to 3500 rpm .any more surestions

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#6 PostAuthor: snotie1965 » Wed Oct 28, 2015 9:31 am

jez1100r wrote:Droped pilot jet to 35. From 37.5 ,air jets now at 2.25 turns out . Starts better .still have flat spot at 2500 rpm to 3500 rpm .any more surestions

i would jet down on your mains , on my ut i ended up all 4 the same ,no need to have bigger mains on 2-3 ! {i got that info from this site}.
go down one size at a time ,and test / plug chop , mine is on standard settings and 147.5 on all 4 with A.P.E foam air filters and V & H pipe (race baffle)
if i try and quieten the pipe to much it runs shit slow and motor gets hot !!!
do not use cheap air filters !!

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Pigford
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#7 PostAuthor: Pigford » Wed Oct 28, 2015 10:52 am

These are CV carbs (?) - always a real trial to get them working when not on standard set-up (pipe/filters). :??
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#8 PostAuthor: snotie1965 » Wed Oct 28, 2015 11:04 am

Pigford wrote:These are CV carbs (?) - always a real trial to get them working when not on standard set-up (pipe/filters). :??
Yer mine are lawson 34 mm cv`s as well ! mine pulls clean in top gear from under 2000 rpm right to 8000 no flat spots or problems , but all motors are different ?

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#9 PostAuthor: jez1100r » Fri Dec 18, 2015 8:09 pm

Changed main jets today 2 sizes smaller . On reassembly started fine on choke about 2500 rpm left to warm up after 30seconds or so started to rev at 4000 .pused choke in but stayed a 4000 rpm . Checked al throttle connections nothing wrong.turned air jets down but still ran at 4000 rpm .sprayed wd40 round inlet rubbers no change

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#10 PostAuthor: ZedHead » Sat Dec 19, 2015 12:45 am

Jez, with all that is going on i would bite the bullet and have it dyno'd. It will save hours of guess work


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