Spark Plug Gap

[mingy]

:worship: Hey TTRGuy I was just trying to have some fun with 'ya. Didn't mean for that to come off as a shot. Sorry if that's how it was interpreted.

It is certainly true that nothing learned is ever wasted. So in that vein....You mentioned that the specs called for a .060 gap in your plug and that when you completed a field test your bike ran much better with a .030 gap. I would surmise that this may have less to do with your plug than with the rest of your ignition system. As these systems age they inherently produce reduced voltage due to increased tolerances, dirt, resistance, etc. It may be that you are experiencing an intermittent miss at .060 due to the reduced capacity of the system, not just the plug gap. When you reduced the gap in your test to .030 the plug fired with more regularity (not the ex-lax kind of regularity) and you experienced better performance. However, the performance probably would not have been as good as with a new system producing 100% voltage and a .060 plug.

Just thought this plug thing might not be taking up enough of your time, so I expanded the discussion to the whole system.

Either way, sorry for any misunderstanding, it was unintended, but by the way. Why didn't you pick on Steve.emma? He said it first. :) :)

 

[MrLuckey]

No it wasn't taken that way, I just wanted to make sure people understood that this wasn't some quest for more HP. The bike in question is a 2000 and I don't know if I agree with you that the coil etc has somehow degraded to the point that the optimal gap went from .060 to .030. Aimee has had the bike for over a year now and the gap was set to .030 went she got it. The bike was less than a year old at that point so I don't believe the smaller gap is due to ignition system degradation. I've not heard of people gradually reducing the gap every 6 months or year ya know. Right now I am leaning towards believing that the porting played a bigger role in this than anything. I didn't have time to play with the jetting any with the .050 gap but its something I would like to do. I am very curious if anyone that has had porting work done has played with different spark plug gaps afterwards.

I also think Rich is holding out on us :)

Sorry if my reply seemed kind of pissy but sometimes people jump to conclusions about WHY somebody is doing something - just trying to keep this on track.

 

[Jaybird]

Eddie,
I think you should read over your manual a lil bit more carefully. :)
A 2000 KTM 200 calls for a BR9EVX, gapped at .60mm (.024")

Not bagging on ya, but I knew that .060" was way too much gap for any bike plug.

 

[MrLuckey]

DOH!  Well you are half right Jay, it actually calls for .60 mm (0,024 in) and an NGK BR 8 EG.  The 125's call for the plug you mentioned.  Freaking metric system :)  The original heart and intent of the post still remains though - I am curious if motor mods, fuel etc. would necessitate gap changes.

No wonder then that it ran like crap at .050" -

 

Did I mention that I HATE the KTM manuals being in different languages on different page and having BOTH measurement systems in them :think:

 

Here is something interesting that I noticed while perusing the manual:

OIL/GASOLIN RATIO 1:40-1:60 when using high grade two stroke oil (Shell Advance Racing X), when in doupt, please contact your importer

 

Damn, 40:1 to 60:1 ......

 

[Jaybird]

Originally posted by TTRGuy
Well you are half right Jay, it actually calls for .60 mm (0,024 in) and an NGK BR 8 EG.

Ahh, you ARE paying attention now!  ;)

 

[David Trustrum]

Don’t you go saying bad things about my metric system.

Oohh I’ll get all upset & there’ll be hell to pay when the cleaner sees the mess I’ve made. :whiner:

 

[steve.emma]

TTR GUY when I said "dont worry about it I didnt mean you shouldnt be interested or that it doesnt matter" but when you said 60 thou i kinda wondered if it was .6mm,pretty comen mistake. I agree with DOC that at low rpms type riding smaller plug gaps help to stop carbon fouling as does going to one grade hotter type plug. Hey at least you tried different gaps, found out what worked, and learnt a bit about it.
P.S. the metric system is the way to go !!!

 

[David Trustrum]

the metric system is the way to go

Yeah, it’s miles better.

 

[jmics19067]

Originally posted by David Trustrum


Yeah, it’s miles better.

heh

 

[steve.emma]

You were being sarcastic weren't you David? "miles better". Please tell me that was sarcasam or WHAT WERE YOU THINKING!!??

P.S. at least they won't win the America's Cup!

 

[David Trustrum]

The whole key to subtle humour is not to explain it.

Now that you have, perhaps I can suggest Okie installs a flashing LAUGH box in the corner of the page every time the software detects a nonsensical statement.


Yachting? Pah! Rich man’s sport. I wouldn’t care if the French won it.

 

[SiCnTwIsTdYz]

use the gap according to manufacturers specs, mine is 0.24 thousandths of an inch, you can simply gap spark plugs with a feeler guage

 

[Jaybird]

You can't eyeball 'em?

 

[jmics19067]

bet ya I can get somewheres between way to big and way to small by eyeballin them