Atomisor or needle change ?

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Mike - - Bristol
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Main scooter: Silver Special 195
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Just put a 30mm Delorto on my S3 and it's way too rich. Wouldn't run/rev untill I dropped the needle.
Bit smokey and bogs badly when pulling away (better than when I started tho') but when the revs get up a little pulls nicely.
What would you change first the Needle or Atomisor ?

RT195 with PM exhaust
40 slide
x7 needle
AV2668
70 choke
53 pilot

I read somewhere there were issues with the x7 needle , and thoughts guys.
Thanks.
Adam_Winstone
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AV266 or AV268? The AV266 is common for use with the AV266 when running static ignition, the AV268 is more common when running an advance/retard ignition as it often needs to be richer for the additional ignition advance at lower revs. Top needle clip position or first down is quite common for the AV266 X7 combo.

AV264 is used by many with X7, however, it is often better to then change to an X13 or X2 needle as the X7 can run a little weak with the AV264.

One thing to watch out for is people quoting small atomisers and needle combos as a number of dyno operators modify needles so that the number value then becomes irrelevant.

Good luck.

Adam

PS - Watch out for holes in PHBH white floats as this is too common an issue, which makes the float sit low, the fuel level too high, and everything too rich!
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fastfrog
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53 for pilot is maybe too rich. Try 45 to 50.... Got the same prob on mine.....
Size matters!
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Architecten
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Try x7 2nd clip, AV266, 48 idle. Works for me after having same issues.
Mike - - Bristol
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Thanks guys, maybe should have mentioned I fitted a 12.5 litre tank which seems to have effected the carbration a bit so running without a filter.
I'll give it a try over the weekend, fingers crossed.
johnd
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I would agree that an X7 on the second weakest position and an AV266 will probably be a better starting point but also check that your choke plunger is seated correctly first. This can play havoc with the way your bike feels even if its only raised by a fraction of a mm!!
Mike - - Bristol
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Joined: Sun May 02, 2010 2:46 pm
Main scooter: Silver Special 195
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The choke seems fine, that was one of the first things I checked.
The tank has made a difference, had a 26mm on before which was close and running ok.
After fitting the tank wouldn't run with the foam filter on, I know others have had the same issue.
Just means the start point is a bit richer than if there was more air circulating under the panels.
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