Quick jetting question (really)

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wanaride
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Quick jetting question (really)

Post by wanaride »

I cranked my bike this past Saturday with temps in the upper 20s. (I haven't touched the jetting since the summer.)

The bike was harder to start than normal, and the engine was revving WAY higher than normal at idle. (I didn't think to pull out the choke as a test.) Once on the trail, the bike ran very well with no bog. Anytime the bike idled, however, the revs went up a lot.

This means that the bike was jetted too lean for the temps, yes?

I did turn the air screw in to 1/2 turn out and it didn't make a difference.
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krazyinski
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Post by krazyinski »

This means that the bike was jetted too lean for the temps, yes?
yes is the answer.

I had the same problem a week ago dam thing wanted to rev to the moon on the first kick when cold and I didn't like riding with the high idle the 1/4 -1/2 throttle was way to zingy for me thought I lost my mind and forgot how to ride. After a good beating by a local tree I realized my error a change was needed.

I just went through the whole process of needle adjustment up and down. we had temps for a week with highs in the 40s. I had to drop the clip to the third spot from the top on a DEL, then the temps warmed up to the high 60s low 70s
had to change the clip position back to 2nd from the top. as soon as temps get back up to the mid 80s I will change back to CGM on the 3rd then when it gets to the mid to high 90s I will change to the 2nd from the top.
Last edited by krazyinski on 08:13 am Feb 20 2007, edited 1 time in total.
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canyncarvr
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Post by canyncarvr »

CMG?

Consolidated Mutual of the Grasslands?

Certified Mutual Gas?

Chitlins Mashed potatoes and Gravy?

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skipro3
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Post by skipro3 »

I think that's the needle designation.
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krazyinski
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Post by krazyinski »

Continuous Manual Gas? aaaaaaaaaaaaaahh the errors of my ways !!! but thats been corected and nobody but those that know will be any wiser.
2000 KDX220 FRP Ported,plated cylinder,milled head, FRP bored carb, V force 3 reeds, FMF desert pipe, 10oz FWW, 98 KX forks and oem shock re valved by Pro Action, hyd clutch, fastway pegs, tall seat foam, gripper cover, 29" CRhigh mini bars, Cycra brush gaurds.
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Post by canyncarvr »

I would suppose it is a needle code.

A 44mm L1?

That is so far out of whack..almost 20% more lean than a CEL/K at 1/4 throttle.

No one else getting within 5-6 clips of such a needle doesn't make one wonder why?

Whatever works.

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krazyinski
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Post by krazyinski »

yes it is a CGM 39.89mm L1not CMG needle on a fredette ported cylinder works just fine at 60% humidity, temps in the low 90s on up. DEK-DEL-DEM drips like the valdez, blows spooge all over my jersey.
I did not put this engine together or did I request any of the work done I bought it as is fresh from FRP with plated,ported cylinder, milled head and carb bored to 36mm. that is what the invoice reads I got from the owner.
comparing my jetting set up to any RB jetting setup on a 200 or 220 is not the same.

One must jet to ones own conditions and bike using plug chop or seat of the pants trial and error,or a combination of both. In my case porting is not exact (or at least doesn't seem to be exactly repeatable) and done by the machinist hand, that makes tuning a job of time,jets and needles till it is spot on.

back to origin of the first question extreme temps are caused by pressure changes in the atmosphere air density changes and jetting will need to change.
2000 KDX220 FRP Ported,plated cylinder,milled head, FRP bored carb, V force 3 reeds, FMF desert pipe, 10oz FWW, 98 KX forks and oem shock re valved by Pro Action, hyd clutch, fastway pegs, tall seat foam, gripper cover, 29" CRhigh mini bars, Cycra brush gaurds.
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Post by canyncarvr »

Never believe anything you read....

I looked in the wrong column...sorry. Well...for a CGM anyway. Obviously that's not what started the discussion, 'eh? :wink:

But, you got that part.

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