"7" Range Plug

[Brian]

I don't want to start one of those super-technical, way over my head threads here, I just wanted to know if its OK to use a '7' plug in my KDX. I think I've read where others have done so. Can I safely do this, or am I just asking for problems? Any advice is appreciated :cool:

 

[Mac]

A #7 plug will work fine it's just a little hotter. I wouldn't recommend a #7 if you spend alot of time at WOT but if you do alot of technical riding it should be OK as long as you dont hear any pinging.

 

[70 marlin]

works fine. just keep a close eye on your jetting.

 

[canyncarvr]

re: #7
'Can I safely do this?'

Yes.

'Can I use Quaker State 30W motor oil for premix?'

Yes.

How's that??


All hilarious funnery aside, the chances of a #7 causing a problem are slim-to-none. Chances of it being perceived as beneficial are purty good!

 

[Brian]

Good deal :cool: I think I'm still on the rich side as far as jetting, although I do have some hesitation issues right off idle. I think it's rich because I have to clean it out a lot. I thought the BR7ES plug would help in that area. It didn't a whole lot. So maybe I'm too rich? I though hesitation meant I was too lean? Right now I'm at 155/45 with Boyesen reeds, a KG-35 pipe, and no airbox lid. How's that sound?

 

[canyncarvr]

I feel a 'way over' sermon coming on......;)

Nah...I'll give you the cliff notes version!

You don't change the heat range to resolve a jetting 'issue'. A correctly jetted kdx won't have a problem with an '8'. But that's the reason a '7' is commonly used....to 'make up' for a too-rich situation. 'Mask' is a better word. It doesn't 'make up' anything.

While you can get an off-idle hesitation if you're too lean, you're more'n likely too rich. Adjust the airscrew (AS) for best throttle response. Adjust it in small increments..ride it for awhile before you make another change. 'Awhile' meaning a few minutes anyway. 1/16 turn can make a noticeable difference.

While NOone can tell you how to jet for your specific situation thru an email/thread post, I'd guess that a 152/42 would be a move in the right direction for you.

I run 38-40/150-152 @ 2000-3500', 40-55º, but that's with a BEL or CEK needle and a 6/7 throttle valve (slide) respectively. Neither of which means anything for you...just an example of what works in other bikes with other riders.

.......on different parts of the planet!! ;)

And I run an '8'.

You've seen mr. r's posts regarding the same bike, the same day, the same track.....but what you get with different riders?

Check it out @:
http://www.dirtrider.net/forums3/showthread.php?s=&threadid=60392&perpage=20&display=&pagenumber=1

This is a GREAT thread for understanding why you cannot jet 'thru the mail'.

.....and it even comes with pictures!!!!!!

 

[MADisher]

Yeah, what he said, order new jets and while you're waiting for them stick in a 7 and be happy. :)

I thought my KDX was jetted pretty well, and I also felt that the 7 game me a little more snap down low. Now one might argue that the snap, better or lack thereof was because my jetting wasn't spot on, but all the throttle chops I did looked perty darn good, even with the 8. If you get what you want from the 7, it's not likely to do any damage so have at it.

-MD

 

[Braahp]

Try a "BR8EG" instead of the 7ES.