Ivan Posted October 2, 2009 #1 Posted October 2, 2009 I read in another thread, I think started by Monty (Thanks!) about resistor plugs making eh scoot run bad, so, I checked and sure enough... I went to try and get some non resistor plugs, and man what a hassle. The parts guy said no place stocks non resistor type plugs anymore. He was kind enough to call several different places to find a set. So they will be here in the morning. Whew. In the midst of all this, I tried to remove the #4 plug, and it is seized in the head. I learned about this while wrenching cars, so, I can get it out ok, but now I need to find a thread chaser. I was all over town trying to find a 12mm thread chaser, and everyone tried to sell me a tap. After arguing with the 12th guy about the difference between a tap and a thread chaser, I gave up. Does anyone here know where to find a thread chaser for these bikes? Even a brand name or a website would help.
Condor Posted October 2, 2009 #2 Posted October 2, 2009 Try this place.... http://www.ntxtools.com/index.html
Venturous Randy Posted October 2, 2009 #3 Posted October 2, 2009 Ivan, just out of curiosity, was the engine warmed up some before you tried to remove the plug? Also, these plugs need some anti-seize on the threads before they are put in. You did not indicate you have removed the plug so what I would do after I blew around the plug to remove any debris, I would spray a penetrating lubricant around the plug and unscrew it some the screw it back in and keep repeating. You may be able to work some lubricant into the threads and save them. The biggest problem with the plug seizing is aluminum gets stuck to the plug threads and wipes the head threads away as you are removing the plug. Good luck and let us know how it turned out. RandyA
Ivan Posted October 2, 2009 Author #4 Posted October 2, 2009 Nah, I usually remove plugs cold. It doesn't burn that bad that way. One trick I learned while wrenching cars was to warm the engine and try to pull the plug then. Sometimes the heated head will expand enough to loosen a bit. If that doesn't work, your method is next in line. I really don't want to yank the head and heli coil it.
Venturous Randy Posted October 3, 2009 #5 Posted October 3, 2009 Nah, I usually remove plugs cold. It doesn't burn that bad that way. One trick I learned while wrenching cars was to warm the engine and try to pull the plug then. Sometimes the heated head will expand enough to loosen a bit. If that doesn't work, your method is next in line. I really don't want to yank the head and heli coil it. It really does help on aluminum heads as aluminum has a significantly higher expansion rate than steel does when heated. It does not have to be hot enough to burn you, but fairly warm helps. RandyA
Ivan Posted October 3, 2009 Author #6 Posted October 3, 2009 Yeah, I guess I mis-read your post. When I run into one that is seizing, I warm it up. it helps a bunch. Also works with stubborn exhaust bolts and studs.
bobcat Posted October 3, 2009 #7 Posted October 3, 2009 I use non resistor plugs....NGK DP8EA-9 or #5829 I get them at Napa Auto Supply
Ivan Posted October 3, 2009 Author #8 Posted October 3, 2009 I use non resistor plugs....NGK DP8EA-9 or #5829 I get them at Napa Auto Supply Yeah, the guy at the parts store crossed it to that number, so I will have them in the morning.
Ivan Posted October 3, 2009 Author #9 Posted October 3, 2009 Well, I did get them replaced this morning. The scoot runs much better but still has a dead miss on the left rear cylinder. (#3?) I popped out the anti tamper brass plugs on the idle screws and started fiddling with the idle mix. When I got the screw about 6 turns out, the cylinder started firing half way. I guess I need to pull the carbs and rework them again... Not looking forward to it, it was a real PITA.
Art708 Posted October 3, 2009 #10 Posted October 3, 2009 Well, I did get them replaced this morning. The scoot runs much better but still has a dead miss on the left rear cylinder. (#3?) I popped out the anti tamper brass plugs on the idle screws and started fiddling with the idle mix. When I got the screw about 6 turns out, the cylinder started firing half way. I guess I need to pull the carbs and rework them again... Not looking forward to it, it was a real PITA. Left rear, as you sit on the bike, is #1....... I think.
timgray Posted October 4, 2009 #11 Posted October 4, 2009 For reference to others. NGK dp8ea-9 is a non resistor. what crosses to autolite and champion for that number are resistor plugs. It is very easy to get what you think are the right plug but are in fact resistor plugs. Take a voltmeter to the store. if the plugs read from 1K ohms to 6K ohms they are resistor plugs and should not be used. I had the guy at autozone swear up and down that his were non resistor until I showed him. you get a very weak spark when you run resistor plugs with the resistor caps that are standard on our bikes. Also nobody makes a platinum or iridium plug that is non resistor here in the states. I did find you can buy a dp8eix-9 in japan that is a non resistor iridium plug, but they are not sold here in the states and dont even have an entry in any american NGK books. Just a bit of spark-plug info I uncovered this past month with my ignition woes.
camos Posted October 4, 2009 #12 Posted October 4, 2009 If there is a difficulty getting non resistor plugs an option worth considering is removing the resistor in the cap. Just disassemble the cap and substitute a heavy copper wire or even a piece of a nail for the resistor.
Monty Posted October 4, 2009 #13 Posted October 4, 2009 Well, why are the stock plugs resistor type? The manual shows a DPR8EA-9, and it even says resistor type in the manual.
bald josh Posted October 4, 2009 #14 Posted October 4, 2009 checked both owners manual and service manual and both call for dpR8ea9, the R i assume is resistor, and there is a dp8ea9, no R...??? manuals have been wrong before, so wich plug is right.ive been using resistors because of the manual, should i change?
timgray Posted October 4, 2009 #15 Posted October 4, 2009 (edited) using resistor plugs AND resistor CAPS will give you a longer but weaker spark. It actually makes the spark last longer, but it is weaker. This is because the coil releases only a specific amount of energy. You either release it all in a powerful fast spark, or you release it as a weaker longer spark. you can make the spark longer and weaker by adding resistance. The resistor is there for EMI and RFI suppression. 5K ohms is what is normal for an older carbeurated ignition system, you start to see plugs get easily fouled when you get over 10K ohms, which can cause hard cold starting or easy flooding. Most modern ignition systems try to make up for this by adding high power coils. the spark is stronger but still longer, The EMI/RFI supression in a modern car is very high up near 20Kohms because of the fuel injectors and more computers in it than the space shuttle did back in the late 80's. Our bikes have about a 7000Volt coils, compared to a 2009 Grand AM that has over 40,000 volt coils. They have 5X the resistance for RFI/EMI supression but the coils are firing over 5X the voltage. I like the idea of taking the resistors out of the plug caps. it makes it easier to find plugs that work well AND gives you the option of going back if needed. I would use a 12 AWG solid wire bent over and doubled and then file the ends flat to make a solid copper replacement for the resistor in the cap. Lack of a resistor or not using resistor plugs will simply increase any EMI/RFI noise the system makes. That can show up as spark noise in the FM radio. It wont hurt the bike, and in many cases removing the resistor in the plug by using a non resistor plug OR removing it from the cap will increase spark strength but shorten it's duration. Which usually means easier starting and better resistance to fouling if it did not start on the first crank and you soaked the plugs in gas. Edited October 4, 2009 by timgray
Ozlander Posted October 4, 2009 #16 Posted October 4, 2009 I thought you guys were full of chit, so I went out and checked. My bike, on the one cap I checked has 11k resistance. Having said that, my bike has always had DPREA-9 resistor plugs in it. Thats what came in it and that's the second set is that's in it now. I have never had a starting problem. I'm surprised somebody hasn't recommended Sea Foam and a carb sync. That seems to be the cure all here for everything from flat tires to a dirty windshield. Bike won't start, sync the carbs, back fires, sync the carbs. Got a miss at 140 mph, put some Sea Foam in it and sync the carbs. LOL:hurts:
timgray Posted October 5, 2009 #17 Posted October 5, 2009 (edited) Yes, seafoam + adding nitrogen in the tires + a carb sync will cure baldness. That said, your bike has stronger coils, has the moon aligned right, has enough road angle bells, you are the perfect weight for it to work perfectly. Every bike is different. I have a friend with a XS750 that will NOT start cold. we have to kick start it with a fresh battery to start. I removed the resistors from his caps, they looked like new so no corrosion, and now it starts easily every time. His coils only put out only 3.5K volts when the battery is low during a electric start. If your bike runs fine.... DONT TOUCH ANYTHING.... just ride.... Edited October 5, 2009 by timgray
Ivan Posted October 5, 2009 Author #18 Posted October 5, 2009 FWIW I have synched the carbs. I did rebuild them too, but for lack of finding those absolutely stupid rubber plugs that block the jet galleys in the block, I used the old ones. I suspect this to be the culprit. When I get back to work, I am going to machine some aluminum plugs that use small orings.
bald josh Posted October 5, 2009 #19 Posted October 5, 2009 to the ozlander, love the seafoam and sync bit, it does get a bit repetitious...seriously addatives can only help things, they cannot fix, but to tim grey, you sound extremely well informed and knowledged so no direspect, in fact i would like to pick your brain... so my ?s more resistance creates a longer spark (but weaker) is this a way to compensate for sloppy timing? what is RFI/EMI and last, but not the last i will ask you...i just bought new plug caps with wires from a joint called cedar grove motors llc in WI. ngk caps with copper core wires and 5 ohms resistance built into the caps (look real nice, @40 $ ) so do i run resistance plugs or get the non resistance ones. i have stripped all of my radio/cb/tape /electronic what not so do not care about noise or etc.
Monty Posted October 5, 2009 #20 Posted October 5, 2009 RFI=Radio Frequency Interference EMI=ElectroMagnetic Interference.
saddlebum Posted October 5, 2009 #21 Posted October 5, 2009 RFI=Radio Frequency Interference EMI=ElectroMagnetic Interference. In laymans terms that means static noise coming from your radio or cb speakers
bald josh Posted October 5, 2009 #22 Posted October 5, 2009 Thanks, electrical is not my forte. So do i run with the non resistor or the resistor plugs? this will keep me up tonight
Ivan Posted October 5, 2009 Author #23 Posted October 5, 2009 The only reason for resistors inthe secondary ignition system is the reduction of RFI. If you don't run some type of resistor, you will never have a crystal clear audio system. I notice you took it all out of your scoot, but when you pull up to someone at a stoplight, it will make their radio crackle and pop, so I would recommend not revving the engine much so they don't figure out its you doing it.
Guest tx2sturgis Posted October 5, 2009 #24 Posted October 5, 2009 I thought you guys were full of chit, so I went out and checked. My bike, on the one cap I checked has 11k resistance. Having said that, my bike has always had DPREA-9 resistor plugs in it. Thats what came in it and that's the second set is that's in it now. I have never had a starting problem. I'm surprised somebody hasn't recommended Sea Foam and a carb sync. That seems to be the cure all here for everything from flat tires to a dirty windshield. Bike won't start, sync the carbs, back fires, sync the carbs. Got a miss at 140 mph, put some Sea Foam in it and sync the carbs. LOL:hurts: Finally a wise-ass after my own heart. Bravo!
Ivan Posted October 5, 2009 Author #25 Posted October 5, 2009 My wife was going to leave me until I used some SeaFoam and synched my carbs.
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