Differences

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--- techtalk:ref:genmsr02 [2019/09/19 02:23]
hippysmack [Reading Spark Plugs]
+++ techtalk:ref:genmsr02 [2022/02/11 22:42]
hippysmack [Reading Spark Plugs]
@@ Line 13: / Line 13: @@
 It takes some time and experience before you will be confident reading spark plugs. ((wedge of the XLFORUM http://xlforum.net/forums/showthread.php?t=1110630&page=4)) \\
 But once you master any plug reading method, it is a window into the engine that is invaluable in tuning. \\
-As such to be called an exact science. \\
 Note that for a Sportster, it is quite normal for the front plug to look lighter/leaner than the rear. \\
@@ Line 21: / Line 18: @@
 The difference is due to variations in the air cooling, turbulence in the manifold and differences in exhaust lengths. ((FoxsterUK of the XLFORUM http://xlforum.net/forums/showthread.php?t=461641)) \\
-  * Start with new, or extremely clean recently new plugs.
+====== Quick Check Visuals ======
-  * The best readings are taken by running the vehicle at sustained speeds in the range that you are checking. \\ (I.E., “Wide Open”, Mid Range”, “At or near Idle”) \\ Then disengaging the clutch, killing the engine cleanly, and coasting to a stop.
+Examine plugs as soon as they have been removed. \\
-  * Overall readings can still be taken without a clean kill and stop, even without new plugs. \\ This is still very accurate, and one of the best tune up tools you have. \\ Just make sure that you have good plugs and by keeping an eye on them as you make changes you can read the effect that the changes made. \\ This just requires a mental track record or a written one.
+Deposits on the plug base are an indication of the plug efficiency and are a guide to the general condition of rings, valves carburetor and ignition system. ((1986 HD Dealer FSM pg 7-13)) \\
+  * A wet black or a shiny deposit on the plug base, electrode or ceramic insulator tip indicates an oil fouled plug. \\ May be caused by worn rings, pistons or valves.
+  * Dry fluffy or sooty black deposits indicate a too rich air/fuel mix or too long periods of idling.
+  * A light brown glassy deposit indicates an overheated plug. \\ May be accompanied by a cracked insulator or erosion of the electrode. Caused by a too lean air/fuel mix, a hot running engine, valves not seating or improper ignition timing. \\ The glassy deposit is a conductor when hot and may cause high speed mis-firing.
+  * White, yellow or light tan to rusty brown powdery deposits indicates balanced combustion. \\ The deposits may be cleaned off at regular intervals.
 ====== Before Reading Them ======
@@ Line 31: / Line 32: @@
 Plug reading can get very complex and detailed. \\
-Be careful about using pictures of plugs that may from the days of points and oil burning engines. ((XLXR of the XLFORUM http://xlforum.net/forums/showthread.php?t=506958)) \\
+The plugs are read the same way regardless of which throttle position / fuel circuit provided the reading. ((XLXR of the XLFORUM http://xlforum.net/forums/showthread.php?t=1110630&page=4)) \\
-Today’s plugs look a lot cleaner because of clean burning gas formulas, electronic ignitions and more efficient engine designs. \\
+Any carb must be jetted properly at full throttle. \\
-One thing about taking pictures of plugs is the light and camera settings can make big differences in how the plugs look on screen. \\
+But the secret to getting a carb Sporty to run well is getting all 3 throttle positions / fuel circuits correct. \\
-{{:techtalk:ref:carb:spark_plugs_by_xlxr.jpg?direct&300|}} ((photo by XLXR of the XLFORUM http://xlforum.net/forums/showthread.php?t=506958)) \\
+And then fine tune the transitions between them so the engine runs smooth everywhere in the throttle / rpm range. \\
-====== Where to read them ======
+  * Start with new, or extremely clean recently new plugs.
+  * The best readings are taken by running the vehicle at sustained speeds in the range that you are checking. \\ (I.E., “Wide Open”, Mid Range”, “At or near Idle”) \\ Then disengaging the clutch, killing the engine cleanly, and coasting to a stop.
+  * Overall readings can still be taken without a clean kill and stop, even without new plugs. \\ This is still very accurate, and one of the best tune up tools you have. \\ Just make sure that you have good plugs and by keeping an eye on them as you make changes you can read the effect that the changes made. \\ This just requires a mental track record or a written one.
+====== The Plug Chop Method ======
+You will get only a vague idea of the state of your AFR by just pulling your plugs and reading them. ((FoxsterUK of the XLFORUM http://xlforum.net/forums/showthread.php?t=507816)) \\
+This is because the color of them will likely have been set in the last part of your last ride as you rode through town and pulled up at your garage before shutting off. \\
+If you are tuning your carb then you need a slightly more rigorous approach. \\
+The chop method is simple to do and gives good results: \\
+  - Mark up your throttle grip with a turn of masking tape around the grip next to the switch housing. \\ Also put a piece on the switch housing with a single line. \\ On the grip's tape mark a zero throttle mark opposite the one on the switch housing. \\ Now open the throttle fully and mark this on the grip tape. \\ There will be about 1" around the grip between the two marks, mark up 1/8, 1/4 and 1/2 throttle too.
+  - Have a spark plug wrench handy in your pocket or tool roll. Also have a scrap of paper and a pencil.
+  - Find a long, straight, lightly-used section of road where its easy to ride at high speed but you can safely pull over and stop. \\ Finding this road is the hardest bit to the chop method.
+  - With the engine up to temp (this is very important), ride at a steady 1/8 throttle for 1/2 mile or so, the further the better. \\ With the throttle still open hit the kill switch, pull in the clutch and stop.
+  - Pull the plugs, read the color and write this down, don't rely on your memory.
+  - Repeat the above for 1/4, 1/2 and wide open throttle (WOT).
+You now have a pretty good idea of the state of your plugs at the important throttle openings. \\
+Please keep in mind that different types of gas will give different readings. \\
+Also, that race or av gas is more prone to oxidization and storage deterioration, along with the fact that a multitude of types are used worldwide. \\
+Racing applications: ((http://www.keihincarbs.com/tips/gate.html)) \\
+When jetting the main jet, try to remember to jet for the best power for a given track. \\
+An example of this is endurance where you would want to run a main large enough to keep the engine cool. \\
+This means that you may be on the rich side but the engine will fade less towards the end of the race. \\
+Another situation could be a stadium sx track where you spend much more time on the low to mid circuits. \\
+In this case you may be running a main jet that is much smaller than your usual "outdoor" jetting along with a hotter/extended electrode plug. \\
+As you gain experience and knowledge, you will be able to use other methods to determine your jetting. \\
+A good tuner can "feel" most of the circuits by slowly revving a parked bike, or just by looking at the color of the unpainted pipe and silencer. \\
+But in the mean time always remember to change only one calibration component at a time. \\
+The best trackside method to determine the size of the main jet is to fully load the engine on a long straightaway or hill. \\
+At the end of the stretch chop the throttle and hit the kill button simultaneously. The plug is then pulled for a "reading". \\
+====== Where to read them ======
+{{ :techtalk:ref:genmsr:line_diagram_of_spark_plug_1_by_hippysmack.jpg?direct&300|drawing by Hippysmack}}
   * Heat range and timing:
     * The porcelain is used for reading plug heat range, and timing only.
@@ Line 46: / Line 84: @@
 We are only concerned with a good sound engine for fine tuning purposes. \\
+For reading WOT position, inspect the positive electrode and the last 1/4 of the ceramic insulator. ((http://www.keihincarbs.com/tips/gate.html)) \\
+Best power will usually result in a very light tan colored insulator tip and dark colored ring around the tip of the electrode. \\
+The electrode itself should have fairly sharp edges. \\
+Example: \\
+If the ceramic insulator has a nice tan coloring but the electrode has a white ring around the tip (and plug is in correct heat range), then you can easily run a size larger main jet. \\
 ====== How to Read Them ======
+\\
 ===== Reading Ignition Timing =====
 ==== Using the porcelain ====
@@ Line 146: / Line 190: @@
-====== The Chop method ======
-You will get only a vague idea of the state of your AFR by just pulling your plugs and reading them. ((FoxsterUK of the XLFORUM http://xlforum.net/forums/showthread.php?t=507816)) \\
-This is because the color of them will likely have been set in the last part of your last ride as you rode through town and pulled up at your garage before shutting off. \\
-If you are tuning your carb then you need a slightly more rigorous approach. \\
-The chop method is simple to do and gives good results: \\
-  - Mark up your throttle grip with a turn of masking tape around the grip next to the switch housing. \\ Also put a piece on the switch housing with a single line. \\ On the grip's tape mark a zero throttle mark opposite the one on the switch housing. \\ Now open the throttle fully and mark this on the grip tape. \\ There will be about 1" around the grip between the two marks, mark up 1/8, 1/4 and 1/2 throttle too.
-  - Have a spark plug wrench handy in your pocket or tool roll. Also have a scrap of paper and a pencil.
-  - Find a long, straight, lightly-used section of road where its easy to ride at high speed but you can safely pull over and stop. \\ Finding this road is the hardest bit to the chop method.
-  - With the engine up to temp (this is very important), ride at a steady 1/8 throttle for 1/2 mile or so, the further the better. \\ With the throttle still open hit the kill switch, pull in the clutch and stop.
-  - Pull the plugs, read the color and write this down, don't rely on your memory.
-  - Repeat the above for 1/4, 1/2 and wide open throttle (WOT).
-You now have a pretty good idea of the state of your plugs at the important throttle openings. \\
 ====== Tuning ======
@@ Line 193: / Line 223: @@
+====== Plug Pics ======
+Be careful about using pictures of plugs that may from the days of points and oil burning engines. ((XLXR of the XLFORUM http://xlforum.net/forums/showthread.php?t=506958)) \\
+Today’s plugs look a lot cleaner because of clean burning gas formulas, electronic ignitions and more efficient engine designs. \\
+One thing about taking pictures of plugs is the light and camera settings can make big differences in how the plugs look on screen. \\
+{{:techtalk:ref:carb:spark_plugs_by_xlxr.jpg?direct&300|}} ((photo by XLXR of the XLFORUM http://xlforum.net/forums/showthread.php?t=506958)) \\
+|  Orange coloration from octane booster additive. ((photo by thesavageone33 of the XLFORUM http://xlforum.net/forums/showthread.php?t=1820463)) ((photo by thesavageone33 of the XLFORUM http://xlforum.net/forums/showthread.php?t=1820463&page=4))  ||
+|{{:techtalk:ref:genmsr:spark_plugs_1_by_thesavageone33.jpg?direct&300|}}|{{:techtalk:ref:genmsr:spark_plugs_2_by_thesavageone33.jpg?direct&300|}}|

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