Pilot screw adjustment. How many turns for L5 model?

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Bogdan.V
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Pilot screw adjustment. How many turns for L5 model?

Post by Bogdan.V » Thu Aug 06, 2015 11:09 pm

How many times should I turn out the pilot screw for L5 model? I looked in the workshop manual and I did not see any reference for L5 then I looked on the forums but have not found anything conclusive.

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banner001
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Re: Pilot screw adjustment. How many turns for L5 model?

Post by banner001 » Fri Aug 07, 2015 9:17 am

usually between 2+1/4 and 2+3/4 turns out from fully seated, although its different for every bike depending on local fuel, atmospheric pressure, carb mods/age, air filter, downpipes, exhaust...

turn them further out to richen, turn them inwards to lean
UK ZXR400 L3 (1993) - Fully restored and on the roads, my green beast!
JPN ZXR250 A2 (1990) - Revs to 19,200rpm... 'nuff said :smt003

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tailongwan
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Re: Pilot screw adjustment. How many turns for L5 model?

Post by tailongwan » Sat Jun 27, 2020 9:13 pm

Hi all,
Just find this useful post, thanks!
However, my ZXR400L5 still runs lean whereas I turned out already 2 1/2 the pilot screws... It still remain a bit rev before idle and does not rev frankly when I turn the accelerator (need to turn smoothly). Should I turn out 1/8 or 1/4 more ?
I managed to synchronize, idle is around 1300, but i think it is still lean.
I read a lot of information, saying it is air screw, but I really think it is fuel screw (located on the engine side of carbs).
Thank you for your help, sorry for my poor english ;-)
Cyrille

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banner001
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Re: Pilot screw adjustment. How many turns for L5 model?

Post by banner001 » Sun Jun 28, 2020 7:05 am

The screw is definitely a fuel mixture screw, turn it out to richen, screw it in to lean.

I would start by taking your carb apart and fully cleaning it, that means removing all the jets including the pilot jets and getting them ultrasonically cleaned.

Then see if that had made a difference. Also have you changed the exhaust/downpipes/air filter/airbox etc as these all play a part.

It could also be that you need new engine to carb rubbers
UK ZXR400 L3 (1993) - Fully restored and on the roads, my green beast!
JPN ZXR250 A2 (1990) - Revs to 19,200rpm... 'nuff said :smt003

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tailongwan
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My Bike: Zxr400L5

Re: Pilot screw adjustment. How many turns for L5 model?

Post by tailongwan » Sun Jun 28, 2020 10:25 am

Thank you banner001 for advice. I already remove carbs but not completely, not removing all the jets (just vacuum, needles and pilot screws).
I will definitely go for a new and full cleaning session :)

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