**UPDATE** My Seca Woes :( Need Advice guys.

Ok so i got the Seca on the road. Yesterday it ran really good, till i went to come home. I had filled the tank with half a bottle of seafoam added before filling, it ran good for 40 km. The Dez and me did some stuff (prolly 5 hours) but when i went to go home, the bike was stipping and missing on a couple cylinders, but evened out after 10 or so km. Then she ran like a dream the rest of the way home.

This morning i start the bike to goto work. Little choke and away she goes idling fairly nicely. When i go to actually take off, she starts to sputter and back fire, wouldn't idle without dieing.

**Little background info**

I've got a 4-1 supertrapp on her, but where the 4 pipes come together into 1, there is a hole in the collection (can't see how big).

**

So i could actually see the little flames jumping out of this hole when it backfired. 1k rpm 4k rpm it didn't matter, she backfired.

After 10km down the road on my way to work is my first stop sign. She was idling and running perfectly, ran good the rest of the way into work.

Tonight coming home was the same thing, had to baby her in the parking lot for 30 mins till i could even drive her. She spit and backfired for prolly 5km till i got out of town, then she ran perfect the rest of the way home.

i've gone just under 200km since filling her up and she's almost down to the last segment on the atari... not good...

I'm thinking that i may have a couple cylinder running SUPER rich, and a couple running SUPER lean. So the extra hot lean exhaust gas is igniting the not fully burned rich exhaust gas in the pipes.

Does that seem right, or am i way off base? Could the seafoam have done something (carbs were clean).

I'm running 6 plates in my supertrapp right now to compensate for the hole in the pipes, but maybe i went to far with that lol, should i out a few more plates back in?


I've run out of ideas right now, i can provide more info if needed, i've got a few hours tomorrow morning to play with it, i'll find out what the pilots are set for and report back. (i had them set for 4.5 turns out to get her to idle nice. Last time i checked plugs, none were pure white, but a couple had white tips with black around the last threads and way up in the plug.

Voltage measures over 13V when above 2k rpm, lights reflect this as well, BUT i did notice tonight, that when i come to a stop, they are probably half as bright as when i'm driving at speed.


Thanx guys for any help!, i really love this bike when she's runnin right

 

Re: My Seca Woes Need Advice guys.

And exactly how did you set your float levels? Sounds to me like you're absolutely dumping fuel into the cylinders--- sometimes.

Floats.

Dim lights at idle is normal unless you have a brand new battery and every connector and wire on the bike is perfect. Then they still dim, just not as much. You're ok there.

 

Re: My Seca Woes Need Advice guys.

Wouldn't that run good when cold and horrible when hot Fitz? When i got home tonight i could let her sit there idling at 1k and she ran as smooth as silk, no pops or backfires and didn't die out.

Honestly my drain screws are like part of the bowl right now, so no way to check it with clear tube method :/ Also, wouldn't my plugs be completely covered in soot if it was dumping on any cylinder?

Or am i off base here again lol

 

Re: My Seca Woes Need Advice guys.

Hmm i'm wondering if by me takin out plates (from 12 down to 6) that i've just got my pilots out WAAAY too far.

One thing i did forget to mention, the other day, when warm, i could unscrew my idle screw fully and it would idle fine at 1k rpm, i'm pretty sure she should have died if i backed it all the way off the butterfly's.

 

Re: My Seca Woes Need Advice guys.

You said you saw liquid fire in the headers. Raw fuel burning off does that.

Dude, I'm not trying to pee in your cornflakes, but you're shortcutting. Your symptoms point to float levels, you're trying to talk yourself out of it. You can't out-argue science.

Floats aren't set until you do it with the clear tube method; set them dry and check 'em and you'll be way off on at least a couple. That's because the difference between whacked and right on is so slight if you know you bent the tang you went too far.

I'm not making stuff up; I've been through this with two bikes now and you either do it right or you will be at it for a while-- until you DO it right. (...I almost said do do.)

XJ LAW: NO SHORTCUTS. Forget it and you're doomed. Do it right and you can actually enjoy the bike.

Pull the bowls, screw them to a board, get out the propane torch, use a little Kroil and get them out.

Or screw with the carbs forever until you do. You asked for advice, sorry.

 

Re: My Seca Woes Need Advice guys.

Ya, i really don't wanna have to try that without the correct tools, time is an issue as well till sunday. But i do totally hear what yer sayin fitz.

I can set them roughly by pulling the rack and setting the heights dry. I have the tools to do that at home (I always do work at Dezi's as he has almost any took i need)

So when i set them dry, what do i measure, like do i flip em over and measure from carb body to end of float in a particular spot?

Hopefully checking and setting them dry will get me through this week till i can get those screws out at Dezi's.

I do appreciate your input fitz! remember i've only ever had to deal with 2 carbs before lol the 4 carb is still a little new (as is the feeling of shaft drive)

 

Re: My Seca Woes Need Advice guys.

Yes, but it's only a start. I think it's in the Haynes, or do a forum search.

Honest. Nearly imperceptible, but it shows up RIGHT AWAY in the tube.

DRY SETTING will not be accurate; it might get you closer than you are now but only might.

 

Re: My Seca Woes Need Advice guys.

Those sound also like symptoms of contaminated fuel supply.
What was your reasoning to add Seafoam?

Backing off idle screw past point of control with bike still running can be accomplished if your carbs are out of sync.

 

Re: My Seca Woes Need Advice guys.

K i'll rip the carbs off tomorrow morning and check the dry height, it just has to get me to sunday where i can get those screws out and check fuel level properly. It's just so unrideable as it sits when cold.

mdee* The bike sat for 3 years before i got it, i went through the carbs and they looked and sprayed fine to pilots, polished emulsion tubes etc. I always throw seafoam through my bike gas every few months, just to keep things prestine

I'll report back tomorrow morning with what i find!

Thanx guys!

 

Re: My Seca Woes Need Advice guys.

An easy thing to do is flushing the gas tank. Cleaning the fuel tap and all filters in the gas supply. It helped me once when i had the same symtoms. I added an in line filter to be shure no dirt vas comming to the carburettors.
- and there is a lot af ugly things in an old gas tank.

 

Re: My Seca Woes Need Advice guys.

I can vouch for that.
I took the carbs apart in the beginning of July whilst waiting for supplies from Len and took a look in the bowls... tiny specs of rust lining up the insides of the bowls. The only part that can rust on the fuel line coming to the carbs is the tank. Needless to say, PO had not installed fuel filter.

 

Re: My Seca Woes Need Advice guys.

**UPDATE**

Ok so i reset the pilots first thing today, they WERE as follows from 1-4:

6 - 3.25 - 4.5 - 3.5
plugs looked as follows:

white tip rest black - white tip rest black - dark brown tip rest black - grey tip rest black

I pulled the carbs.. all the floats were WAY too high, set to prolly 12mm or so, so i reset them all to 17mm.

I DID get 3 of 4 drain screws loose.

Carb bottoms were prestine, reinstalled carbs on bike.

Checked the 3 levels that i could all were within 3mm from carb body.

Set all 4 pilots to 3 turns out.

Crossed my fingers and started her up, ran with choke very nicely for a couple minutes.

As soon as i took the choke off she started poppin and back fireing again out that hole.. put the choke on she was fine.

I'll take the truck into work today cause i don't wanna deal with a crap runnin bike lol but what am i lookin at to check now guys?

 

Re: My Seca Woes Need Advice guys.

This is a starting point not the final setting. Also did you vac synch them after playing with the mixes?

 

Re: My Seca Woes Need Advice guys.

There in lies the issue, she seems to not even like the starting point lol

I'll play with the pilots more tomorrow morning. When i FIRST got the bike (like i'm talking the first time i started it) it ran like this, popping and skipping etc etc.. and i turned everything out to 4.5 and it seemed fine after that till the other day.

(I was tweaking to get colour correct, hence the differing numbers I posted above.)

I've only ever done a bench sync so far, i have bottles but haven't done a good sync yet, they should be close enough that it shouldn't be running like it is.

 

No, no NO.

"They should be close enough.."

NO.

Screwing with the pilots before getting a good vacuum sync is doing things backwards.

TO GET IT RIGHT YOU HAVE TO DO IT RIGHT. All you're doing right now is painting yourself into a corner. Of course it "didn't like" the starting point-- you turn the idle knob up a hair, get it running on all 4 and sync it.

THEN mess with the pilots.

Keep up with the shortcuts and you're going to be at this a while...

 

That's the problem fitz, i'm not cutting corners here now, it won't idle, i can run it up to 3k and it still pops and backfires, all this stuff wouldn't be an issue if it actually ran without backfiring.

That's my issue right now. Something is WAY off, when i've got the fuel levels good, the pilots set to where a lot of you guys run them, and i get issues like i have, there's something terribly off that i can't find. That's where i need some advice that i may have been stupid and forgot.

It's hard to start the normal tuning process when i can't even get the bike to run at all right when it's cold.

THAT is what mystifies me about it... struggle through the crap running when it's cold and then it runs like a dream, will idle all day, no problem whatsoever.

It's acting like it's running WAY lean, but you advised me it must be raw fuel in the exhaust somehow. So i need to find out why it's doing the backfiring (all of a sudden remember too) THEN i'll have no problems with the rest.

I know you guys are trying to help, but telling me i'm trying to cut corners still, when I do what you suggested, and it didn't help any, isn't helping my issue to improve. I really need to just find out what i can check and look for that will solve the backfiring when cold problem.

Sync should be set so it won't do what it's doing, i checked that again today. Pilots should be set to at least get a good idle.. it's not.

 

if you think it's lean a little choke would help it if you suspect rich take the air filter out or pull the vacuum hose to the petcok, plug it and let it start to run out of gas
i'am trying to not make you pull the rack again till you have something to go on
do you have any idea what the throttle shaft seals are like ?

 

I haven't taken the seals out, but i have sprayed ether on the shafts and it didn't change rpms at all, so they seal ok.

I will try those couple things tomorrow morning Pol see what she does, may give me a starting point. as to which way she's running.

I'll report with what i find in the morning.

 

Your carbs are not all working together. Like you wrote in your original post, some are too lean, some are too rich relative to each other. The procedures to get them working together is multi stepped and ALL the steps must be preformed on each and ALL carbs.

You are having difficulty with doing all steps to each carb due to reasons like drain screws you can’t loosen. Leaving out a step on any carb will likely result in that carb not working properly together with the other carbs. Many different issues with carbs present themselves with similar symptoms. That is one reason to do all the correct procedures. Otherwise it can be difficult to diagnose. It can be easy to convince yourself you have completed all procedures as a whole, when it fact you have not on each carb.

You should set the 4 pilot screws to about 3.5 to 4.5 turns out and set all to the same setting. Then ignore them till all other carb issues are dealt with. More precise settings of the pilot screws will be the last step in tuning after you have float level and sync set correctly.

You sound like you are frustrated because you are considering too many possible causes. Try to focus on the procedures you have completed with the most confidence as a process of elimination.
I think you should get that stuck drain screw out of the last carb so you can be confident of the wet float level.

My example story:
I ran into difficulty syncing my carbs because the left adjusting screw was rusty and would not turn smoothly. I had seen it was rusty, but I skipped the bench sync adjustment because all carbs matched on bench. I did not want to bother with the rusty screw if I did not need to. But then on bike when I attempted to balance (sync) carbs I became confused with the procedure results I was getting. Took me a while to realize the rusty screw was jumping high and low and also pushing idle too high and low. My lesson re-learned is try harder to do ALL a given procedures steps in the proper order. Otherwise I will likely be doing the skipped procedure later on when it’s more difficult, time consuming and frustrating.

 

That's the exact reason why when i first got the bike, the first thing i did was go through the carbs, and reset the pilots.

I have been reading this site for 2 years, so i have amassed a large amount of info, and technique over that time. I usually only post when something, be it an adjustment or whatnot, doesn't react the way it should.

The big stink in this whole thing, is it ran perfectly for a few weeks and then BAM, i'm stuck with what it's doing now.

The problem i'm having with the whole "leave the pilots till last" is if i ran at 0.5 turns out or i run at 6 turns out, i should have VASTLY different problems. Most ppl start at 3 turns to get running then tweak from there, which of course i tried and failed. So i can't really tell if anything else is buggered till i get an idling bike.

That's why the first thing i'm doing tomorrow is check the plugs from my test start this morning, and see what the plugs tell me, then adjust pilots and idle set screw till i get a smooth idle, that will rev without hanging or backfiring at any throttle level.

Once i get a running bike, the fine tuning is nothing.

If i sound frustrated from considering too many possibilites, it's because there COULD be THAT many things to consider, that's causing my problem.

I'm not so much frustrated, as i am baffled that my 400 and this 750 are such completely different beasts in reacting to my troubleshooting. BUT i'm not even close to giving up. The 400 didn't beat me, this bike won't either lol.

 

Have you tried a new set of plugs yet? If you fouled the plugs and make repairs then try to tune on fouled plugs the symptoms will be the same because the plugs are fouled from the start get new plugs there cheap. Are your pilot screws fine thread or course thread? Sometimes you have to ask yourself if the bike ran good before i screwed with it what was the last thing I did that must have messed things up and can i undo it. IE i dumped half a can of sea foam in the gas tank when my bike was running fine. If I have a stuck screw or nut, bolt I spray it with pb blaster or Kroil oil shoot it in the place where you would put the hose to check the fuel level the bowl drain and the head of the screw try to do this a few days in a row before you actually try to break it loose. Have you read Lens bible on carbs yet? Dont use starting fluid to check for air leaks on shaft seals or boots thats a good way to blow yourself up a cracked coil (The bike is 30 years old) arching to the frame right above where you spray the carbs and good bye hand its hard to ride a bike with only one hand. Take the time to do it right the first time use common sense to eliminate whats not wrong IE i know for a fact that the float levels are correct in ALL the carbs See the word ALL ALL ALL now I can move on to the next unknown carbs are synced to the engine etc. Sometimes a cylinder is so sooted up from being over rich that it holds the valves open. I think I fixed the issue with the carbs but the thing still runs bad . Once I get a bike running I take it out and exercise it IE I get on and ride the crap out of her keep the rpms in the 5k and up I am not saying run her up to 120 mph but get her hot and burn all the shit out of the cylinders these are high r bikes. bring it home pop in a new set of plugs and tune it out.

 

I was almost afraid to ask:

When was the last time the valves were checked?

And Waldo is right; 3 out of 4 won't do it if the fourth is what's screwing you up.

 

Valves are checked and all 8 have been replaced to make them in spec, about 400 km ago.

@Waldo, thanks for your input but theres this: Posts: 667 under my name the common stuff has all been done, of course new plugs are in it.

That last carb (you're all gunna lose it on me after this) i can't see how it could be SO far out that it's dumping gas through the cylinder and into the exhaust, all 4 are set to the same dry height. Which gave me the 3 i could check a perfect level. i seriously doubt that that one 4th would be THAT far off from the rest.

Plug read will follow, i'm sure i can 100% say that it's NOT gunna be soot fouled. So no gas dump there.

 

just a thought... are you sure your cam chain is on right? SURE it's not out of time a tooth or two?

 

That 4th carb being dry set to match the others is an assumption to be correct wet height. Making assumptions is the point I was trying to convey (in previous post). You are likely correct in that assumption, but think about how frustrating it would be to disqualify the real issue because of an assumption and try to fix the real issue by repeatedly confusing your self with attempts at fixing other things that are in fact not broke.

One possibility is the float in that one carb with stuck drain screw is reacting different to fluid (gas). Possibly it’s leaking, possibly the seat & needle is not working properly.

Since the bike was running so good just before it began running bad, you should very thoughtfully retrace what changes you did just before this issue appeared. One thing it sounds like you did was to add Seafoam to gas. It’s also possible that for some reason the carbs became contaminated AFTER you cleaned them. Do you have an in-line gas filter? If so have you installed a NEW in-line fuel filter (not reused old after carb rebuild).

 

There's a simple fix to your stuck screw and I didn't see it posted here before.

Switch bowls between #3 which you already checked by clear tube and #4 and now you can check #4 by clear tube to be sure.

 

iwingameover – that’s a good idea !

Another possibility is the YICS ports have become plugged with carbon. I don’t know if you cleaned YICS galley and verified the ports are open. But after adding that high dose of Seafoam, it likely shook loose some carbon off the intake valves. I found some carbon in my previously cleaned YICS galley after adding Seafoam.

 

i'd like to see a compression test just to rule valves out
if a cylinder isn't firing because it's too rich the plug is going to come out white because there was no fire to make it black
all of the observations should be made with the choke off and the motor at least close to temp
i tried to reread the whole post but my head hurt, anyhow do a running sync, even if it's running bad and you need to keep it around 2.5K, at least check it

 

Ok sry for not posting this morning but i was so into what i was doing i had no time to post before work.

So i had her running pretty good just before i left. urned all pilots out to 5 turns for a starting point.

Found #3 cyl. wasn't firing almost at all, was fouled pretty bad. I cleaned it up and it was firing normal after, but i'm not 100% sure i'm gunna leave it.

Sync'd the carbs with bottles, they weren't that far off (maybe 1/8th turn), but now they're perfect, so that's done.

Went for a quick ride around the block, it ran great at first, then as it warmed up a touch it started to miss (NOT backfire tho, so that's good) did a plug chop from 4k as i came into the driveway, didn't have time to check them, i'll do that first thing tomorrow morning and see what's running tan and what's not (If any are)

Hopefully i've got it narrowed down to fine tuning now (Gunna keep an eye on that #3 plug tho)

I don't have a comp tester here, and i don't think Dez can find his, so that may not happen sry Pol

It did seem to be more powerful than it was. Will see what i can find out tomorrow and report back.

 

That's another thing i'm definately going to be doing tomorrow, NEW gas! and get her to operating temp to see how she runs, and tune.

It's nice to have 3 hours or so to fiddle before work

 

my suzuki vtwin did the same spitting and sputtering.

one cylinder had no connection inside the plug cap and wire. the cap literally came off the wire. the terminal was burnt black.

cleaned the terminal. cut 2mm off the plug wire. SCREWED the cap back on.

PROBLEM SOLVED.

my yamaha also did the same thing. it had loose vacuum line to fuel switch. and leaky intake gaskets. that fixed the backfiring. but it needed a tci box to make it run like a champ at the low rpm range under 4k.

 

don't put much more time in it before you get some new plugs

 

Uhg these plugs have 200km on them lol i suck again, if they're really bad when i look at em tomorrow i'll get new. I hate throwing 20 bux down the drain lol.

 

Oh and i do have 4 brand new plug caps, and i cut a 1/2" off every wire before i screwed em on.

 

Actually i will order a box of non resistor plugs tomorrow. I didn't wanna run 5k caps and R plugs to begin with.

ALSO!! i'm gunna put back in the plates i took out of the supertrapp, cause it actually ran decent when i had that number in. Maybe i got a little over zealous when i went down to 6.

 

They charge you $5 apiece for spark plugs over there?

I never pay more than $2 for NGKs at the local auto parts. You oughta make a run over here and buy a box of 10.

 

How close to the start of your problems were the R plugs put in? Addnig resistance will weaken the spark. Weak spark = slow burn = bad running = low power = fuel in the exhaust.

 

It ran actually really well for quite a while with the double resistance. I was worried about that same thing, slow weaker spark, but it didn't seem to bother it too much, the 400 didn't seem to care to much about double resistance either.

That was from a Yamaha place in Woodstock Fitz, so they were gold plated I'll order them from Napa, i think they're a bit cheaper, problem is, they don't stock those plugs, so it's a day or so wait for em, which is no big deal i can't get out there till sunday at the earliest anyways.

 

Ok so no love this morning. I think I've got ignition/electrical issues now, i'm trying to source new non R plugs, but it's becoming a futile exercise. So i may have to just get the BPR7ES and live with it.

What's happening now, is it will run fine above say 3k but misses under that, it'll drop 1 or 2 cylinders it sounds like. I've checked spark on all 4 this morning, and #4 is definitely having issues. Wether that's the ignitons fault or the plugs fault, we'll find out when i get new ones.

Both coils read 22k across 1-4 and 2-3 spark plug leads. It's been a while since i've had to read up on how to test resistance through them tho, so i may have to search for that.

Primary's and pickups tested ok back when i was first going over her, but i will check them again or good measure.

OR, I've possibly got a flakey TCI (GOD I HATE TCI'S)

I'll check the connectors around the tci tho, i am having odd electrical issues as well that i have to track down. For example, if i take a known working flasher relay and stick it on my harness, i get no signal lights. The flasher that's on it is a 550 Werner i think. It flashes really slow when the bike is off, and it's almost a constant signal on when at 3k.

Needless to say, i've got a full weekend ahead of me... :/

 

$3 bux a plug for the BPR7ES from Napa, i got 8 on order for Saturday.

 

You don't want the R's. BP7ES is what you want.

Also 22k ohms seems high. I was just checking mine the other night and my book says 11k ohms which is what I read and my bike is running great.

Is the 750 spec different?

Did you maybe get 10k ohm plugs caps instead of 5k ohm caps?

Mine dropped the spark on 2+3 and it ended up being the TCI.

 

Hey KrS14 you can get the BP7ES plugs at Canadian Tire. Thats where I get mine. I'm Down at Normandale and picked mine up in Simcoe. My primaries and secondaries where just in spec on my 83 XJ750. But just to be safe and considering the age of the parts I changed to to the Dynatech coils, new wires and caps. And as Bigfitz52 says you can not take any short cuts. I know I tried. Do it right the first time, especially if your on a budget like me. I want my bike on the road but that wont happen till next year hopefully for the May Friday the 13th.

 

No, the 81->83 are the same.
I would be very leery of upsetting the resistor balance on the ignition system for fear of improperly loading the coils and potentially harming them or the TCI. Proceed with caution.

 

If he's measureing 22K ohms across the plug wires he's already cross that bridge.

Add in resistor plugs as well at 5k each and you're trying to spark across 16K ohms per plug!

Maybe all that extra resistance it trashing a plug wire slowly.....

 

I don't think it will trash the spark plug wire, I'm concerned with the coil winding inside the coil. It is engineered to put out a good spark at so much resistance, add to it and you could cause too much current to flow and burn out the coil.

 

The service manual says the coil itself should be 11k. Without the plugs in WITH the caps on, i got 22k, that's 5k+5k (caps) +11k (coil) = 22k just what i measured, so my coils are ok.

I'm pretty sure i've just got bad plugs that are sparking out way up inside the insulator, or just so fouled they can't jump all the crap AND the air to spark, I've got the 8 on order, plus i'll pick up some non R's from crappy tire

**( Thanx Hugger for that )**

Hopefully i can get the carbs set so it won't foul anymore, AND won't be so lean that pop. *crosses fingers*

I do work till 5 tomorrow so i won't be reporting back till later on sat night.

Again, thanks for chiming in guys!

 

KrS14 the OP of my XJ had resistor plugs in my bike. As aesult my spark was very weak so I changed out the plus. Things improver but not much. My coils tested 21.6 on the secondaries but the spar on 2&3 was weak. So I opted for new coils wires and caps as two cap where at 8Kohms. I ended up changing coils, wires and caps. The checking fatory coils guide below I got from chacal.

Checking Factory Coils:

Factory Yamaha coils need to "see" a total load resistance on the secondary side (the "going-to-the-plugs" side of the coil) of around 20-30K ohms (ohms being a measure of electrical resistance). Electrical resistance depends on a number of factors: wire size, type of material, length of material, ambient temperature, etc. etc.

In any case, all factory XJ coils and wires combined---BUT WITHOUT THE CAPS OR PLUGS ATTACHED---have the following primary and secondary resistance ranges:


For all models except XJ700, XJ750-X, and XJ900 models:

Primary (input from TCI): 2.5 ohms +/- 10%
= 2.25 ohms - 2.75 ohms acceptable range

Secondary (output to spark plugs): 11K ohms +/- 20%
= 8,800 ohms - 13,200 ohms acceptable range


For all XJ700, XJ750-X, and XJ900 models:

Primary (input from TCI): 2.7 ohms +/- 10%
= 2.43 ohms - 2.97 ohms acceptable range

Secondary (output to spark plugs): 12K ohms +/- 20% (XJ700 and XJ750-X)
= 9,600 ohms - 14,400 ohms acceptable range

Secondary (output to spark plugs): 13.2K ohms +/- 20% (XJ900)
= 10,560 ohms - 15,840 ohms acceptable range


In order to help diagnosing engine performance problems that seem to be "plug-related", always measure the resistance of your coils, both primary and secondary sides, before you start replacing parts. 20+ year old coils can and do fail regularly. If you need to replace your coils, and decide to buy used, original coils "sight unseen", always make sure that the seller checks them for you before you buy them!

 

There was a good thread not too long ago about using resistive plugs and caps together, basically it shouldn't affect ignition any, but it DOES cut down on interference in radios, or any other type of electronic equipment, because it makes the spark last longer (resistors act as current limiting).

So you get a fatter longer spark, were as you get a quick crisp spark with less resistance.

I have done the secondary check, and all was fine.

 

Well I was told that if you want to use resistive plug you have get rid of the caps because they are resistive and put the regular caps on that are used on cars/trucks. The resistance created by the resistive plugs is enough to cause sparking problems, very weak. Bike coils do not put out the same amount of spark as a car/truck does. The caps act as current limiting also, 5K ohms, resistive plugs anther 5K ohms, so where you should have 5K you end up with 10K so you really have is 22+10+10 = 32K . you system is designed to run at a specific resistance level. If you use resistive plugs you HAVE to include there resistance in the equation. Also the caps do the same as what resistive plug does. Believe me the only advantage of a resistive plug you don't need a special cap. The spark is no different then a normal plug. Resistance means LESS spark.

 

Good read on an explanation here:

http://www.ultralightnews.com/enginetro ... dplugs.htm

Some argue that the slower spark burns better.

Either way it' shouldn't affect our bikes at all when it comes to running.

EXCEPT when he talks about debris on the plug, if it's fouled, even slightly it may cause the plug to not fire, which is what i'm seeing. So i can almost bet it's my plugs that have had it