It doesnt make sense to me

Why when my #1 plug cap is on it wants to run like s@#t until i pull it off and hold it over the plug so you can hear the snapping of the spark and it runs smooth. I dont understand it the spark has to jump to the plug not a direct connection it should be the otherway around.

 

When you do that you're increasing the voltage in the spark (it won't jump until it builds up.) I'll bet the resistor core in that plug cap is loose, or you need a new plug.

 

Thanks Fitz i kinda figured the coil should be good cause it runs the other cyl.plus it takes longer for that exaust header to warm up to the temp of the other ones.Ill check the cap and plug thanks

 

It could also be a fuel fouled spark plug. I use that technique to diagnose them. I do it so often I keep a spare spark plug laying on my bench to put in the cap to give me the extra gap.

Sometimes a couple minutes at high rpm will even cook the plug back into working order.

Pop $3 for a new plug before you go chasing resistors in the cap.

 

that's a good way to test the caps too

 

Sorry Fitz havent checked yet its pouring out

Thats what happens #1 cold on startup (compared to the other 3) until i Rev it up a bit seems to come to life(header gets hot).I know i have the plugs i had in the bike when i bought it wich were non resistors type.BUT i cant buy new ones here in Canada without the reisistors.How do you check the caps for the resistors?(outer cyl) the inner caps unscrew but i dont see where you would unscrew the inner werkings of the outer ones?

 

errr no...you aren't increasing the voltage in the spark. That's impossible! It just so happens he has enough juice to jump the extra distance to earth anyway. Something else is going on here. Maybe the plug is faulty and it runs like crap with intermittent firing. When you hold it away from the plug you are getting smooth running on just 3 cylinders only? What's more, if you have a resistor in the cap AND the plug, you are throttling the available voltage. Just have one or the other! Try a known good plug in that cylinder and report back.

 

The theory is that the secondary voltage will shoot up until the voltage is high enough to ionize and jump the spark gap. Larger gap, means higher voltage required to ionize and jump.

What you're doing with the cap off the plug is putting three gaps in series, and none one of them will jump until they all do.

One could argue, however, that each individual gap will still see only part of the voltage, and each original gap should still see the same voltage as before.

Not sure what this has to do with the OP's issue, but anyway...

 

You can either order resistor plugs from chacal or you can order new caps from him that do not have resistors. I got the non-resistive caps and bought resistive plugs at CT.

 

New" known to be good "plug in #1 cyl.Runs good but # 3 seems to take its time warming up.Coil issue?

 

What was meant by this is a one-time cook off to burn the gas out, not that this would be the case each time you start up.

Another way to *possibly* restore a fuel fouled plug is to "cook" it with a propane torch. That *may* clear the fuel but as I understand it, it is a 50/50 chance.

 

What about eliminating all resistors what would that do?I know they are there for a reason but what if ya got new non resistor caps and plugs?

I am going to get 4 new plugs see what happens

 

You have to have 1 set of resistors.

There should be one in the spark plug wire. If not, then you need it on the spark plug.

I could be wrong but, I thought the easy way to tell was the size of the connection in the plug boot. If if is only big enough to take the top of the plug with the resistor off, then the cable had the resistor and you didn't want it on the plug. If the electrical connection inside the boot fits onto the plug with the resistor in place, then you needed it. So, unless you somehow forced it, you really couldn't get it wrong.

 

I can only get resisted plugs and I removed the resistors in the inner caps and replaced them with metal dowels and installed 4 new resisted plugs gapped to .030 fired right up ran like a champ then ran out of fuel