Adjusting AirFuel screw

mediace · December 12th, 2016, 08:23 AM

EL250
Adjusting Air Fuel screw with idle screw both run at 1200+-
Engine already Warm up
Done Valve adjusting
Running test/adjusting one at a time

Carb one
run adequately at settings 2 1/2 turn, set to 2 3/4 turn

Carb two
Problem to run smoothly at same idle screw setting (default at 2 1/2 turn)
Need to increase throttle for engine to run

What is possible cause..?

Thanks in advances

jkv45 · December 12th, 2016, 09:12 AM

Blockage in idle mixture passages on carb #2 would be my guess.

Have you synced the carbs? I would try that and see what that shows you. If there is a problem it's going to take significant adjustments to get them close. At that point it's showing you they need to come off and be gone through.

mediace · December 12th, 2016, 09:37 AM

Quote:

Originally Posted by jkv45

Blockage in idle mixture passages on carb #2 would be my guess.

Have you synced the carbs? I would try that and see what that shows you. If there is a problem it's going to take significant adjustments to get them close. At that point it's showing you they need to come off and be gone through.

Done bench sync and will do manometer sync after try cleaning it again thoroughly.

jkv45 · December 12th, 2016, 11:10 AM

Quote:

Originally Posted by mediace

Done bench sync and will do manometer sync after try cleaning it again thoroughly.

Be sure to remove the idle mixture screws and confirm a spring, washer, and o-ring, on each. The o-ring can tear and get stuck in the passage. Spray cleaner through the passages and confirm they are open.

Float levels should also be checked, as well as removing and carefully cleaning all the jets and other passages.

mediace · December 13th, 2016, 04:40 AM

it seem my bike will have different vac pressure when throttling from idle position. possible butterfly valve leaking/gap or pilot jet or something else that i'm not so sure.

Done idling manometer check and settle for now.

December 12th, 2016, 08:23 AM	#1
mediace ninjette.org newbie Name: din Location: malaysia Join Date: Dec 2016 Motorcycle(s): el250 Posts: 5	Adjusting AirFuel screw EL250 Adjusting Air Fuel screw with idle screw both run at 1200+- Engine already Warm up Done Valve adjusting Running test/adjusting one at a time Carb one run adequately at settings 2 1/2 turn, set to 2 3/4 turn Carb two Problem to run smoothly at same idle screw setting (default at 2 1/2 turn) Need to increase throttle for engine to run What is possible cause..? Thanks in advances

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Adjusting clutch.	ZeroGravity360	2008 - 2012 Ninja 250R Tech Talk	16	May 21st, 2016 04:40 PM
2008+ Ninja 250 Carburetor Screw size, allen screw size!	Runeknight95	2008 - 2012 Ninja 250R Tech Talk	4	March 2nd, 2015 11:49 AM
Adjusting headlights?	uKER	2013 - 2017 Ninja 300 Tech Talk	2	July 8th, 2013 07:50 PM
Adjusting the Idle Mixture Screw	conrya5	2008 - 2012 Ninja 250R Tech Talk	22	March 18th, 2013 05:03 AM
Help with adjusting the values	Ingersoll	2008 - 2012 Ninja 250R Tech Talk	2	January 14th, 2010 08:08 AM

December 12th, 2016, 09:12 AM	#2
jkv45 Rev Limiter Name: Jay Location: WI Join Date: Jul 2013 Motorcycle(s): '06 SV650n, '00 Derbi GPR, '64 CA77 Dream 305, '70 CL450 Scrambler, numerous dirt bikes Posts: A lot. MOTM - Jun '18, Oct '16	Blockage in idle mixture passages on carb #2 would be my guess. Have you synced the carbs? I would try that and see what that shows you. If there is a problem it's going to take significant adjustments to get them close. At that point it's showing you they need to come off and be gone through.
	1 out of 1 members found this post helpful.

December 13th, 2016, 04:40 AM	#5
mediace ninjette.org newbie Name: din Location: malaysia Join Date: Dec 2016 Motorcycle(s): el250 Posts: 5	it seem my bike will have different vac pressure when throttling from idle position. possible butterfly valve leaking/gap or pilot jet or something else that i'm not so sure. Done idling manometer check and settle for now.