Differences

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--- techtalk:ref:genmsr02 [2019/09/19 05:12]
hippysmack [Plug Pics]
+++ techtalk:ref:genmsr02 [2022/02/11 22:42]
hippysmack [Reading Spark Plugs]
@@ Line 18: / 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)) \\
+====== Quick Check Visuals ======
+Examine plugs as soon as they have been removed. \\
+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 34: / Line 42: @@
-====== Where to read them ======
+====== 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 45: / 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 ======
 \\
@@ Line 146: / Line 190: @@
-====== 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. \\
 ====== Tuning ======

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