Differences

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--- techtalk:ref:carb07 [2024/01/11 23:28] – hippysmack
+++ techtalk:ref:carb07 [2024/11/12 07:03] (current) – [Idle Mixture Screw - IMS - Aftermarket & Mods] ixl2relax
@@ Line 19: / Line 19: @@
 |Long idle speed screw on a Keihin CV. ((photo by Hippysmack))|
 |{{:techtalk:ref:carb:cv_carb_with_extended_idle_speed_screw_by_hippysmack.jpg?direct&300|}}|
 \\
@@ Line 32: / Line 31: @@
 {{:techtalk:ref:carb:cvp-partsforcv40-1.jpg?600|}} ((pics from BestCoastXL at https://www.xlforum.net/forum/sportster-motorcycle-forum/sportster-motorcycle-intake-and-exhaust/sportster-motorcycle-air-intake-carburetor-efi-fuel-and-exhaust/202758-should-i-buy-carb-parts-from-amazon-rather-than-cv-performance-no-you-should-not?t=2079965 - Annotated by IXL2Relax))
 ====== Idle Mixture Screw - IMS - Aftermarket & Mods ======
 \\
 **CVP EZ-Just IMS**\\
-The EZ-Just mixture screw (for L76-87 or 88-06 models) ((https://cv-performance.com/ez-just-mixture-screw-81-87-harley-keihin)) ) can be purchased with an extended screw head for hand tuning. \\ You can buy packing from CVP also in case yours has been damaged or is not functioning properly. \\ But, check your local regulations before changing this out to an aftermarket part. \\ You can also find, buy or barter for used parts. \\ ("Please note: it is a violation of federal law to tamper with or disable any emission or noise control device. That is your PSA for the day"). ((XLForum member - chrishajer)) \\
+The EZ-Just mixture screw can be a handy upgrade. It allows you to get your fingers on the larger screw head rather than using a small screwdriver as required with the stock idle mixture screw. The EZ-Just is compatible for L76-87 or 88-06 version Keihin CV carbs.((https://cv-performance.com/ez-just-mixture-screw-81-87-harley-keihin))
+You can buy packing (spring, washer & o-ring) from CVP if your OEM parts have been damaged or are not functioning properly - BUT - Check your local regulations before changing IMS Settings or using aftermarket parts. **Please note:** "It is a violation of federal law to tamper with or disable any emission or noise control device. That is your PSA for the day."((XLForum member - chrishajer))
+**Proper Screw Setting** - The taper of the CVP EZ-Just screw has a longer and wider profile versus the OEM screw. This results in a different fuel flow ratio per turn compared to the OEM screw. This still allows finding the right turns setting with the CVP EZ-Just, but it won't necessarily be the same number of turns as the OEM screw.
+No one should simply pick a particular number of turns out from a light seat as a final setting. Picking a starting point is appropriate, but you really need to use the Idle Drop Method of tuning to find the right number of turns for the Idle Mixture Screw. Variations in the idle port orifice (due to wear or damage, etc.) along with variations in the different screws (OEM, CVP, Chinese aftermarket, etc.) makes it important to rely on the Idle Drop Method of tuning, rather than simply picking a number of turns. Any number of recommended turns out on the IMS screw, whether using OEM or aftermarket parts, is only an initial starting point and not specified as a final, properly tuned setting.
+The final setting should always be based on the preference of the individual engine setup as found by the Idle Drop Method.
+[[techtalk:evo:carb02#the_idle_drop_method_idm_for_setting_idle_fuel|CLICK HERE]] for an explanation of the Idle Drop Method at the CV carb tuning page in the Sportsterpedia.
+The pic below shows the taper dims from both the OEM and CVP IMS screw. Although different from each other, both are capable of reaching a proper adjustment of the fuel mixture for correct idle operation.
+{{:techtalk:ref:carb:ez-just_88-06_a-f_mixture_screw_1_by_hippysmack.jpg?direct&300|}} ((photo by Hippysmack, OEM dims by John Harper)) \\
+\\
 If you still have the factory plug over the mixture screw, you'll need to drill it out to access the screw. \\
@@ Line 43: / Line 56: @@
 Then pry the plug out using a pick or you could twist a small sheet metal screw into the hole to pull the plug out. \\
 With the plug removed clean the area around the mixture screw so no metal fragments remain. \\
-{{techtalk:evo:carb:cv40-imscap-drillbit.jpg?300|}} ((photo by cantolina of the XLFORUM http://xlforum.net/forums/showthread.php?t=14949)) Circled area is where you drill out the plug. {{:techtalk:ref:carb:cv_carb_bottom_by_cantolina.jpg?direct&300|}} ((photo by cantolina of the XLFORUM http://xlforum.net/forums/showthread.php?t=14949))
+{{techtalk:evo:carb:cv40-imscap-drillbit.jpg?300|}} ((photo by cantolina of the XLFORUM https://www.xlforum.net/forum/sportster-motorcycle-forum/sportster-motorcycle-intake-and-exhaust/sportster-motorcycle-air-intake-carburetor-efi-fuel-and-exhaust/9621-carb-adjusting-where-are-the-jets-and-the-mixture-screw?t=14949)) Circled area is where you drill out the plug. {{:techtalk:ref:carb:cv_carb_bottom_by_cantolina.jpg?direct&300|}} ((photo by cantolina of the XLFORUM https://www.xlforum.net/forum/sportster-motorcycle-forum/sportster-motorcycle-intake-and-exhaust/sportster-motorcycle-air-intake-carburetor-efi-fuel-and-exhaust/9621-carb-adjusting-where-are-the-jets-and-the-mixture-screw?t=14949))
 The EZ-Just mixture screw must be threaded in completely (lightly seated) prior to backing out and making final adjustments. \\
@@ Line 66: / Line 79: @@
 If you take off the bowl, be sure to check the float setting before reinstalling the bowl. \\
-|  EZ-Just Screw in it's 'lightly seated' position. ((photo by Matt Black of the XLFORUM http://xlforum.net/forums/showthread.php?t=2068828&page=6))  ||
+|  EZ-Just Screw in it's 'lightly seated' position. ((photo by Matt Black of the XLFORUM https://www.xlforum.net/forum/sportster-motorcycle-forum/sportster-motorcycle-intake-and-exhaust/sportster-motorcycle-air-intake-carburetor-efi-fuel-and-exhaust/193103-newbie-cv-rebuild/page6?t=2068828&page=6))  ||
 |{{:techtalk:ref:carb:ez_screw_lightly_seated_1_by_matt_black.jpg?direct&300|}}|{{:techtalk:ref:carb:ez_screw_lightly_seated_2_by_matt_black.jpg?direct&300|}}|
-|Comparison to OEM. ((photo by Hippysmack))|  As installed on bottom of carb. ((photos by Hippysmack))  ||
+|  As installed on bottom of carb. ((photos by Hippysmack))  ||
-|{{:techtalk:ref:carb:ez-just_88-06_a-f_mixture_screw_1_by_hippysmack.jpg?direct&300|}} ((photo byHippysmack))| {{:techtalk:ref:carb:ez-just_88-06_a-f_mixture_screw_2_by_hippysmack.jpg?direct&300|}} ((photo byHippysmack))|{{:techtalk:ref:carb:ez-just_88-06_a-f_mixture_screw_3_by_hippysmack.jpg?direct&300|}} ((photo byHippysmack))|
+|{{:techtalk:ref:carb:ez-just_88-06_a-f_mixture_screw_2_by_hippysmack.jpg?direct&300|}} ((photo byHippysmack))|{{:techtalk:ref:carb:ez-just_88-06_a-f_mixture_screw_3_by_hippysmack.jpg?direct&300|}} ((photo byHippysmack))|
 **CVP Easy-Just IMS - Modding**\\
-From RandallM of the XLForum((Post#80 - http://xlforum.net/forums/showthread.php?t=2081062)) - Here is how I indexed my screw. I filed some small flats on a small nail, and JB Welded it in the slot. I left the small end sticking out a bit so I can feel both ends.
+From RandallM of the XLForum((Post#80 - https://www.xlforum.net/forum/sportster-motorcycle-forum/sportster-motorcycle-intake-and-exhaust/sportster-motorcycle-air-intake-carburetor-efi-fuel-and-exhaust/203772-jet-hole-size-chart?t=2081062)) - Here is how I indexed my screw. I filed some small flats on a small nail, and JB Welded it in the slot. I left the small end sticking out a bit so I can feel both ends.
 {{techtalk:ref:carb:cvp-easyjust-ims-mod6.jpg?direct&300|}}
@@ Line 84: / Line 97: @@
 Several mods to the thumbscrew have been done to make counting turns while turning the screw easier. \\
-|The aftermarket thumb screw head doesn't have a slot for a screwdriver (which can serve for visual positioning). \\ A small hole drilled off center will give a visual position of the screw for adjustment later. ((photos by sifty of the XLFORUM http://xlforum.net/forums/showthread.php?t=1592463&page=48))||
+|The aftermarket thumb screw head doesn't have a slot for a screwdriver (which can serve for visual positioning). \\ A small hole drilled off center will give a visual position of the screw for adjustment later. ((photos by sifty of the XLFORUM https://www.xlforum.net/forum/sportster-motorcycle-forum/sportster-motorcycle-era-specific-and-model-specific/ironhead-sportster-motorcycle-talk-1957-1985/146604-first-harley-1975-xl1000-caf%C3%A9-project/page48?t=1592463&page=48))||
 |{{:techtalk:evo:carb:idle_mixture_screw_3_by_sifty.jpg?direct&300|}}|{{:techtalk:evo:carb:idle_mixture_screw_4_by_sifty.jpg?direct&300|}}|
-This replacement needle makes it so much easier to adjust the idle mixture. ((Folkie of the XLFORUM http://xlforum.net/forums/showthread.php?t=183642)) \\
+This replacement needle makes it so much easier to adjust the idle mixture. ((Folkie of the XLFORUM https://www.xlforum.net/forum/sportster-motorcycle-forum/sportster-motorcycle-intake-and-exhaust/sportster-motorcycle-air-intake-carburetor-efi-fuel-and-exhaust/47776-idle-mixture-needle-mod?t=183642)) \\
 However, it is easier to count the turns by hand with this mod. \\
 A spigot was added to the face of the knob. \\
@@ Line 93: / Line 106: @@
 Then the side nearest the air cleaner (right of bike) was marked to index when to stop turning to the right. \\
 The needle was then removed, drilled and tapped (10 BA) for the spigot. \\
-You can also drill hole through the knob from side to side and Superglue a screw in it. ((Hot Rod Sporty of the XLFORUM http://xlforum.net/forums/showthread.php?t=183642)) \\
+You can also drill hole through the knob from side to side and Superglue a screw in it. ((Hot Rod Sporty of the XLFORUM https://www.xlforum.net/forum/sportster-motorcycle-forum/sportster-motorcycle-intake-and-exhaust/sportster-motorcycle-air-intake-carburetor-efi-fuel-and-exhaust/47776-idle-mixture-needle-mod?t=183642)) \\
 The EZ-Just makes it easy to adjust the idle mixture by hand without a screwdriver. \\
-But, if you've gone 3 to 3-1/2 turns out, then change to the next biggest slow jet. ((Folkie of the XLFORUM http://xlforum.net/forums/showthread.php?t=183642)) \\
+But, if you've gone 3 to 3-1/2 turns out, then change to the next biggest slow jet. ((Folkie of the XLFORUM https://www.xlforum.net/forum/sportster-motorcycle-forum/sportster-motorcycle-intake-and-exhaust/sportster-motorcycle-air-intake-carburetor-efi-fuel-and-exhaust/47776-idle-mixture-needle-mod?t=183642)) \\
-|  Spigot installed to count the turns. ((photo by Folkie of the XLFORUM http://xlforum.net/forums/showthread.php?t=183642))  |
+|  Spigot installed to count the turns. ((photo by Folkie of the XLFORUM https://www.xlforum.net/forum/sportster-motorcycle-forum/sportster-motorcycle-intake-and-exhaust/sportster-motorcycle-air-intake-carburetor-efi-fuel-and-exhaust/47776-idle-mixture-needle-mod?t=183642))  |
 |{{:techtalk:evo:carb:idle_mixture_screw_mod_by_folkie.jpg?direct&300|}}|
@@ Line 107: / Line 120: @@
 A piece of 3/16" brass tubing and a knurled nut from the hardware store. \\
-|  Factory idle mixture screw extended. ((photos by tchuck of the XLFORUM http://xlforum.net/forums/showthread.php?t=183642))  ||
+|  Factory idle mixture screw extended. ((photos by tchuck of the XLFORUM https://www.xlforum.net/forum/sportster-motorcycle-forum/sportster-motorcycle-intake-and-exhaust/sportster-motorcycle-air-intake-carburetor-efi-fuel-and-exhaust/47776-idle-mixture-needle-mod?t=183642))  ||
 |{{:techtalk:evo:carb:idle_mixture_screw_mod_2_by_tchuck.jpg?direct&300|}}|{{:techtalk:evo:carb:idle_mixture_screw_mod_3_by_tchuck.jpg?direct&300|}}|
 \\
@@ Line 132: / Line 144: @@
 |{{:techtalk:ref:carb:velocity_stack_3_by_hippysmack.jpg?direct&300|}}|{{:techtalk:ref:carb:velocity_stack_4_by_hippysmack.jpg?direct&300|}}|{{:techtalk:ref:carb:velocity_stack_5_by_hippysmack.jpg?direct&300|}}|
 ====== Replacing the Plastic Fuel Inlet Fitting with a Brass 90 Degree Fitting ======
@@ Line 145: / Line 155: @@
 |{{:techtalk:ref:carb:cv_fuel_inlet_elbow_mod_7_by_hippysmack.jpg?direct&300|}}|
-|  Keihin butterfly (non CV). Here is on way to do it. Break the plastic off and run a hose on the factory brass nipple. ((photos by Hopper of the XLFORUM http://xlforum.net/forums/showthread.php?t=209347&highlight=float+level&page=21))  |||
+|  Keihin butterfly (non CV). Here is on way to do it. Break the plastic off and run a hose on the factory brass nipple. ((photos by Hopper of the XLFORUM https://www.xlforum.net/forum/sportster-motorcycle-forum/sportster-motorcycle-era-specific-and-model-specific/ironhead-sportster-motorcycle-talk-1957-1985/50355-and-yet-another-77-ground-up-rebuild/page21?t=209347&highlight=float+level&page=21))  |||
 |{{:techtalk:ref:carb:keihin_butterfly_carb_23_by_hopper.jpg?direct&300|}}|{{:techtalk:ref:carb:keihin_butterfly_carb_24_by_hopper.jpg?direct&300|}}|{{:techtalk:ref:carb:keihin_butterfly_carb_25_by_hopper.jpg?direct&300|}}|
 Replacing the the hipple with a brass elbow is detailed below. \\
 ===== Tools =====
@@ Line 161: / Line 172: @@
 {{:techtalk:ref:carb:cv_fuel_inlet_elbow_mod_tools_by_hippysmack.jpg?direct&300|}} ((photo by Hippysmack))
 ===== Part Considerations =====
   * Brass 90° elbow
@@ Line 246: / Line 256: @@
 I pre-made puller was bought for the pics below. \\
 But you can also use a 1/4'x20 threaded rod about a foot long screwed into the fitting. \\
-Then slip a thin piece of pipe nipple over the rod with a washer and nut onto the end of the rod. ((tgrover of the XLFORUM http://xlforum.net/forums/showthread.php?t=501871)) \\
+Then slip a thin piece of pipe nipple over the rod with a washer and nut onto the end of the rod. ((tgrover of the XLFORUM https://www.xlforum.net/forum/sportster-motorcycle-forum/sportster-motorcycle-era-specific-and-model-specific/ironhead-sportster-motorcycle-talk-1957-1985/72657-what-carb-is-this-and-how-do-i-set-it-up?t=501871)) \\
 Place the spacer (or deep socket) over the brass nipple. \\
@@ Line 258: / Line 268: @@
 A socket may be used as a spacer with the appropriate length bolt. \\
-{{:techtalk:ref:carb:socket_as_spacer_for_removing_cv_carb_inlet_by_matt_black.jpg?direct&300|}} ((photo by Matt Black of the XLFORUM http://xlforum.net/forums/showthread.php?p=5685578&highlight=fuel+inlet+elbow#post5685578)) \\
+{{:techtalk:ref:carb:socket_as_spacer_for_removing_cv_carb_inlet_by_matt_black.jpg?direct&300|}} ((photo by Matt Black of the XLFORUM https://www.xlforum.net/forum/sportster-motorcycle-forum/sportster-motorcycle-intake-and-exhaust/sportster-motorcycle-air-intake-carburetor-efi-fuel-and-exhaust/193103-newbie-cv-rebuild/page7?highlight=fuel+inlet+elbow#post4213142)) \\
 {{:techtalk:ref:carb:cv_fuel_inlet_elbow_mod_17_by_hippysmack.jpg?direct&300|}} {{:techtalk:ref:carb:cv_fuel_inlet_elbow_mod_18_by_hippysmack.jpg?direct&300|}} {{:techtalk:ref:carb:cv_fuel_inlet_elbow_mod_19_by_hippysmack.jpg?direct&300|}}
@@ Line 287: / Line 297: @@
 Blow the passage out again to ensure of no debris before installing the bowl. ((photos by Hippysmack)) \\
 {{:techtalk:ref:carb:cv_fuel_inlet_elbow_mod_40_by_hippysmack.jpg?direct&300|}} {{:techtalk:ref:carb:cv_fuel_inlet_elbow_mod_41_by_hippysmack.jpg?direct&300|}} {{:techtalk:ref:carb:cv_fuel_inlet_elbow_mod_42_by_hippysmack.jpg?direct&300|}} \\

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