changed clip position and needle, still bogging down

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lammysilver
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Wed May 05, 2010 10:38 am

28mm del, 42 clubman, old SR kit...

was bogging from idle - 1/4 throttle with:
105 main, 55 pilot, aq264, X2 (clip 2nd from bottom), 40 slide.

first i moved the clip up, leaned off a bit but not massively.

Went ahead and got an X7 and X13 needle, after trying the X7 then fitting the X13 (the leaner of the two) its still bogging down off idle.

I was thinking of trying a leaner slide and pilot maybe?

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GP Kevo
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Wed May 05, 2010 11:12 am

The needle really comes into play between 1/4 and 3/4 throttle so yes, probably a leaner pilot jet will bring results you want.

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joeythescooterboy
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Wed May 05, 2010 11:52 am

X13 is richer than the X7 not leaner kid.
Nemo saltat sorbius, nisi infanus est.

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RinB
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Wed May 05, 2010 4:41 pm

Dont forget the Slide acts in this part of the throttle in the progression period

Try a 45 -50 slide or take 0.5-1mm of the cut out
If its made of Metal Fettle it !!

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sean brady scooters
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Wed May 05, 2010 5:17 pm

something strikes me as odd here...
if its a 28mm phbh carb then an AQ 264 would not fit in ...so maybe its an AV 264,either that or maybe you have a smaller PHBL carb...?
Sean Brady Scooters - 01765 690 698

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lammysilver
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Wed May 05, 2010 7:10 pm

yeh X7 the leaner of the two, thats whats in there, and its a AV264... my fingers hit the keys a bit too quick! Apols for any confusion!! :D

To update i Just got a 50 pilot to replace the 55 and ill be trying that later.

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Diablo
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Wed May 05, 2010 8:26 pm

Lee have you tried adjusting your mixture screw?
Most bikes with your set up work well with an x7 needle

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lammysilver
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Wed May 05, 2010 10:03 pm

Cheers, ill be trying the leaner '50' pilot in there with X7 (clip adjusted to suit), then tweak the air/mixture screw , fingers x'd, sorted.
See how it goes then if needs be i'll take a look at the slide.

Read the post you put up Al, (motocross carb tuner), good one that, I also found this quite helpful... http://www.lambretta.co.uk/downloads/carbsetup.html

Eitherways Al all going good i should be up visiting soon mate.

eibargum
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Thu May 06, 2010 1:53 pm

If all else fails your right to do what R in B [smiffy] suggest,s, only take 0.5mm off at a time, i had to do this on are lass,s 28mm BHPH to get it to run cleanly at the bottom end, but only after i,d try,d everything else, worked a treat :D .

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Special X
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Sat May 08, 2010 8:42 am

45/50 slide (or modify the existing slide) 50/52 idle should sort it along with a bit of tinkering with the mixture screw. 105 seems a tad small on the main . . I'd have reckoned 110 was nearer the mark. Despite what many people will tell you the idle jet affects the mixture right through the range. Also check that the choke is seating correctly and closing right off as these carbs suffer from choke leakage which affects the lower throttle openings badly.

Hope you get it sorted . . there's nothing worse than nagging carb problems.

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