spark plug gap

[mack]

For those of you who switched to the accell 403 coils, did you change the gap in your plugs to the .035 in. Also what jetting changes did you make if any.

[natemoen]

Shouldn't have to rejet just for coils.

[Rasputin]

I have the 140403's in my 79SF. I did not change the spark plug gap at first. The spark was so good I did end up going to .040 and it ran better (from a seat of the pants point of view). No solid proof that the .040 was necessary at all. There was no reason to change any jetting. The only thing you are doing is providing a hotter spark so jetting, if it is correct before will not change.

[mack]

Just wondering

since they are a hotter coil, would it make the bike run to the leaner side.

[cywelchjr]

How hot the coil is should not affect the mixture at all. It may make the engine run a bit faster and cause you to need to turn the idle speed down a bit, but even that may not happen.

[BA80]

[natemoen]

What are you rolling your eyes about?

[79XS11F]

since they are a hotter coil, would it make the bike run to the leaner side.

When I changed out my coils to the Excel "high performance" units I gaped as per the manual that came with the coils. The larger spark they should deliver is suppose to be hotter and ignite the gases more uniformly and more fully. There's not much sense is installing high output coils and then using the standard short gap = short spark. The manual does suggest checking for a potential lean burn after installation so it would not hurt to keep an eye on it. More so if your running a leaner exhaust system and or other mods.
Rob

[Rasputin]

When I changed out my coils to the Excel "high performance" units I gaped as per the manual that came with the coils. The larger spark they should deliver is suppose to be hotter and ignite the gases more uniformly and more fully. There's not much sense is installing high output coils and then using the standard short gap = short spark. The manual does suggest checking for a potential lean burn after installation so it would not hurt to keep an eye on it. More so if your running a leaner exhaust system and or other mods.
Rob

I had forgotten about that Rob. You are absolutely correct. If you zoom in on this pic it does say exactly that.

[mack]

Thanx

I opened the box yesterday and no manual was present, just a hand written note on the bill saying to increase the plug gap. Thanx for manual Rasputin and the input Rob.

[Rasputin]

Here are the other two pages that came with them. I just posted the one and did not think of it as a manual. So without further ado is the whole thing that came with my 140403 coils.

[cywelchjr]

Ok, I'm stepping up to admit I appear to be wrong, the stronger spark can apparently affect the mixture, which means as much as I HATE pulling carbs, and as much as I do NOT want to rejet, I'm reconsidering aftermarket coils. One of the things I like about riding year round is the fact that the only time I've had to pull the carbs when when I changed the engine. Some seafoam every 3 months or so and it just keeps going smooth and strong.

[natemoen]

It isn't that the mixture changes it is just that the mixture is more completely and efficiently burned. I think most tend to run a little more on the rich side and I bet that the better spark just slightly moves it from a little rich to adequate, but worth checking. Should check the plugs every so often anyways.

[cywelchjr]

I do, every time I change them. They check out pretty much right on.

Now that I've bragged something will go wrong! That's why I don't take my laptop out into the garage to type on here, I don't want the bike to know what I say. It's the same with not discussing finances in the car or out in the garage, cause the vehicles will make sure something breaks that takes up the extra every time. I am glad to have a working gas gauge again, but of course as soon as I got that fixed it starts raining (thunderstorms with hail and possibly tornadoes).

[mack]

rich/lean

I haven't installed the Accell's yet. Everything is still stock, but the time will come. Just wanted to have all the info when I do swap.I had offered them out to phil if he needed new coils to get his ride diagnosed. As for mine,
I actually tune "Hermes" using one set of plugs all gapped the same. Then I put in a set of running plugs with 1&4 being gapped closer to 0.07mm and 2&3 gapped closer to 0.08 mm. By the color of the plugs, 2&3 do run SLIGHTLY richer and that is my intent. I know many will say that running the inside cylinders richer is not required. So I'm probably wrong as well. But it's working like a charm for me.