Fiddling with the carb and RB mod

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canyncarvr
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Post by canyncarvr »

Re: '..it is humbling..'

Something everyone should realize every day. No sense in worrying about it much...'cuz what one doesn't know will always and forever far exceed anything one DOES know. And that's true even when you throw in the stuff that some think they know (and don't)!

Instead, enjoy the search for and procurement of knowledge and information.

There is always room for more when it comes to things that need learnin'. Might as well have fun doin' it!

Don't lose sight of what all this (bikes, riding) is supposed to be, at least for most of us. It's supposed to be fun!

So...get to it!!

:wink:

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Post by billys04kdx200 »

Alls i can say is ,Thanks. All the stuff i've read on here and done to my bike, has made the riding 10 times funner. Thanks again for all ya'll have taught me.
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kicknrocks
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Post by kicknrocks »

CC,

when you say the CEK-4, do you mean CEK in the number four position? This was the setting I tried most recently, but reverted back to the original middle clip (#3) because of some crackling under load (too rich I believe).

Here's something I noticed, not to dispute your comments about the value of plug reading. In the #3 position, my plug appears rich after a idle-1/4 throttle run, but dry after a full throttle run. Might this be resolved by changing to a less steep taper? By my assessment, the same needle diameter with less taper would allow less fuel in lower throttle, and more at higher throttle.
'01 KDX 220
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RB Designs Carb
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fuzzy
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Post by fuzzy »

How much have you tried to tune that out with the air screw?
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'95 KDX 200 Project $600 KDX
'94 WR 250 Always a project
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2001kdx
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Post by 2001kdx »

CEK-4 would mean the clip in it's 4th position; the clip being just underneath the middles position.
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kicknrocks
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Post by kicknrocks »

haven't messed with the AS yet
'01 KDX 220
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Post by fuzzy »

That's your problem. Put the needle at #4, and use the air screw to tune loew-end....Sounds like you need to lean it, which would be turning it out.
'91 KDX 200 Project $300 KDX
'95 KDX 200 Project $600 KDX
'94 WR 250 Always a project
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canyncarvr
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Post by canyncarvr »

>|<>QBB<
kicknrocks wrote:haven't messed with the AS yet
You can't not tune the air screw with a modified carb. You will never get it sorted out.

CEK-4: The '-4' is the clip position..as noted in the graphic.

On a general note...if your preference is a clip position that is different..great!! As long as the method you use makes some sense, the conclusion you reach that suits you is what you're after...not what everyone else says.

In regard to method, specifically..will a less steep taper resolve the 'too rich' on the 'bottom' you describe?

Fact is..that is exactly incorrect. Other things being equal, a steeper taper is lean LONGER (through a throttle pull) than is a lesser taper.

IF that's a 'DOH' moment for 'ya...fine. If not..say so and I'll say why it's so.

The RB carb originally came with an AEN needle. Smaller taper, so leaner on the bottom of the pull? Uh...absolutely not. MUCH richer. That needle was SUCH a goober.....it was a complete mess. If the bike wasn't 4-stroking it was because you were eating lunch or taking a pottie break.

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