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fishhead I have question
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Posted by: freydog---------------------
I ride in the puget sound area year round. According to my calculations, this time of year I should be running the stock 48/160 jets. The consensus here is stock is way to rich, but the calculations don't lie. I was running a 155 jet and decided to do a plug check today at walker valley (1500ft, 40-45 deg F). Was very suprized to see a stark white plug, with not even a hint of color. With a plug that white, should I even bother with a 158? or just go back to the 160.
I've also been battling a lean bog problem ever since I removed the airbox lid. Moving the clip to 4th position helped a lot. should I move to 5th position, or does that create some sort of wierd jetting imbalance. Instead, can you recommend a needle, and clip position? thanks much.
Posted by: canyncarvr---------------------
Although you're in the same geo area as fishhead, your bike setup (size?, ported?, modifications?) is part of the equation.
If he knows you already,fine...if he doesn't, you should include that info as part of your question or he's not going to be able to give you much of an answer.
From a fairly recent post of his (9-24-2001):
Quote:
Currently I run 152 or 155 main depending on temp and altitude
pilot a 38 or 35
|
Granted, it's cooler now than it was in september.
I don't know what your 'calculations' are ..but 48/160 is pretty big for most cases.
re: lean bog. Where on the throttle? Have you adjusted your AS for best throttle response??...or just high idle?
You might try a PM to him as opposed to a forum thread.
He'll still need to know something more about your bike than 'air cover removed'.....
Posted by: fishhead---------------------
FD
sounds like you are on the right track but 160 might be a bit fat, I am curious what needle and clip positon you are running and any other mods you might have.
I am running a signifacantly different needle profile than stock hence the lean pilot jet. For a basically stock 200 I would try a CEL -3 needle with the stock slide and probably a 42 or 45 pilot My slide was cut to a #7 hence the need for a CEJ needle and I run a 35pilot to clean it up a bit on the bottom
Posted by: freydog---------------------
Thanks guys. I really want to get this thing perfect and decide if it's enough power before spending money on a pipe. I think it will be. I'll try the CEL-3.
To do my calculations I used the chart in "Tech Tips - Carb tuning". According to that I should multiply the jet size by approximately 1.04.
155 X 1.04 = 161.2, and 45 X 1.04 = 46.8. Hmmm, even in that case the stock 48 pilot would be too rich, but the stock 160 would be lean.
Here's a little more on specifics.
-Completely stock 00 KDX200, except for a few dents in pipe:D
-Airbox lid on with snorkel removed and five 1 inch holes drilled
-45 pilot, 155 main, stock needle (1174?) in 4th clip position
-air screw 1/2 turn out
-NGK b8es
-Dumonde Tech DTP synthetic at 32:1, 92 octane chevron
Moving needle clip from 3 to 4 greatly improved the bog, but it's not totally eliminated. Sorry carver I didn't adjust a/s for high idle, but I tried the a/s at 1, 1/2, 1/4, and all the way in. I figured I was so lean that there was no need to experiment with the a/s out farther than 1 turn. that could be where I went wrong (other than the fact that it was obvious a 155 main is too lean!) I still have 2nd and 3rd gear bog at low RPM. at mid RPM it runs awesome. WOT throttle the bike has less power than it had with the 160 main. thankfully I didn't sieze or burn it up.
Posted by: fishhead---------------------
I am curious about the throttle position when the bog occurrs, knowing that bit of info will help to pinpoint which circuit is lean. for instance is it the 0-1/2 area or 1/4 to 3/4 etc. try rolling on the throttle in 3rd gear at slow speed on level ground to isolate the throttle position, marking the throttle with a piece of tape helps. Dont be surprised if a 48 pilot turns out to be best.
As a side note you might want to try a br7es instead of an 8 it will be a little cleaner and on most trails in Wet WA you don't need the 8.
first things first though, if you haven't already,
1) check for air leaks around the carb boot, make sure there are no leaks around the head pipe.
2) use a good grade of fresh premium fuel, preferably without alcohol, Chevron and Texaco around here usually are alcohol free. Alcohol kills throttle response, particulrly around the circuit transitions.
3) check the float level and make sure it's in spec.
4) run a compression test and check the kips for free actuation
5) check the reeds
You are running a high quality synthetic so 32:1 is a lot of oil for trail riding, Jeff Fredette suggested 40- 50:1 for trail riding and that made the jetting process easier.
Hope that helps let us know ow it goes.
Posted by: MisShift---------------------
Hey Freydog....I ride at walker also. Next time there is an event there lets hook up. Know of any events there soon? P.S. Fishhead...does any advice about 200's pertain to 220 carbs also?
Posted by: fishhead---------------------
220's like a little leaner setting because of the smaller carb but I think the needles will work I would start with a cel in the 3rd clip position with the stock slide.
Posted by: freydog---------------------
Maybe removing the airbox lid with a stock exhaust system is not a good idea. Is it possible that the exhaust system does not flow good enough to handle the increased intake airflow? Maybe the airbox lid mod only works with an aftermarket pipe.
I've tried all of the suggestions, except the CEL needle. I plan on ordering it soon. Still battling the lean bog.
MisShift I'll look for info on Walker Valley events. There probably wont be on until summer cause that place is a mudpit right now!
Posted by: Jim Crenca---------------------
Freydog
My modified 94 kDX is also slightly lean with 160 main, 70 degree temp., at 400 ft. above sea level. It runs great otherwise, starts easily, & doesn't appear to have an air leak. I agree with Fishhead about changing to a br7es plug. The 32:1 ratio seems resonable to me for trail riding. I like my bike much better with an aftermarket pipe, silencer, & carb mods. I wish I could keep the power & response with a little less noise though.
Posted by: freydog---------------------
Jim,
Today was the first day riding with the br7 plug. I can't comment if it's better or worse, because of the other changes I made at the same time.
Interesing that you need the 160 main at 70 degrees. I'm running the 160 main again, but today it was only about 40 degrees! If you don't have an airleak, maybe your float bowl level is incorrect. But heck, if your happy with the way it's running, don't mess with it.
I'm going back to the 48 pilot and see if it helps. I did notice some pinging today at 1/8 to 1/2 throttle, so I better richen things up.
Posted by: fishhead---------------------
Freydog
Is that clip positionyou mentioned fourth from the top or from the bottom?
Posted by: freydog---------------------
4th from the bottom (toward the pointed end). Interestingly, I tried the 5th position with the stock needle and a 158 main and the bog moved from 1/4 to 1/2 throttle, to 1/2 to full throttle. there was no bog on the bottom. since i was checking this in a confined area, there was no chance to wind the motor out a little. maybe the 158 with clip in 5th position would work fine.
Posted by: freydog---------------------
I should actually say 4th from the top. I'm moving the clip toward the pointed end of the needle. I consider position 1 at the top and position 5 closer to the middle of the needle, closest to the pointed end. sorry for the confusion.
Posted by: fishhead---------------------
your settings sound richer than average but appear you would benifit from more taper on the needle or a smaller straight diameter since raising the needle moved the bog. The location of the bog is in the area that is primarily controlled by the needle.
It might be helpful to know what needle you are using.
Posted by: freydog---------------------
Still running the stock needle. Not sure what it equates to in the 3 letter code. I know trying the CEL is going to help.
I just read through the huge EMERGENCY RB designs jetting post. I'm sure I can get rid of this bog problem by turning the a/s in further...but the farther I turn the a/s in, the more the bike will blubber when idling along. It seems to run cleaner with the a/s 1 1/2 turns out, but then I have that big bog when I crack the throttle open. Kind of a compromise. Maybe a richer pilot jet with the a/s 1 1/2 turns or more out will get rid of the bog AND the bike will idle cleaner?
Heck, I'm just going to leave the pilot jet alone (running a 45) and order the CEL needle.
Posted by: OLD-N-SLOW---------------------
Go to the 5th position on the needle. As JD said those slots are there to be used. If the bog got better going 3 to 4 try 5.
But in may opinion there is little reason to monkey with it until you get
a cel, cgl or ccl needle. The difference is that big!!!!! Remember though a c--
needle is a richer taper and is going to need a leaner jet set.
On my 200 in fl I run 35-150 cel4 #5 and still would like a little leaner on the low end. I have a cem needle on order. But remember i am in fla.
I have had the best results getting rid of a lean bog by lowering the clip(raising the needle).
Steve
Posted by: freydog---------------------
thanks for all the info guys. I don't know of another place on the web where people know so much about jetting.
I'll try the 5th position until the new needle comes in, with the 160 main.
When I get the cel (and the way I operate it could be a while), from what your saying, sounds like I'll be putting in a 42 or 40 pilot, and maybe using the 155 main.
It's all fun...whatever it takes to give me wheel lift at will. One of these days I'll probably accidently drop a big clod of dirt in the carb while changing needle clip position. Then the real fun will begin.
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