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How many turns out should the idle screw be?

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My idle is outta wack and I dont know which way is up w/ it. I just need a general idea of how many turns out so I can start from there and begin to set my fuel screw because now the bike won't even start :smirk:

Edited by GoonSquadRMZ450

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1. Turn it way up until the bike runs

2. Lower it as far as you can without the engine stalling.

3. Adjust the fuel screw until it smooths out. Go back to step 1. If you cannot get it to smooth out, continue to step 4.

4. Up the idle until it idles smooth.

This is the lowest idle you can have. You may want it slightly higher.

Note that you may want to blow a small fan on the radiator while doing this so it doesn't overheat.

Jim.

Edited by JimDettman
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Go it, thanks Jim. Thats the best response I've gotten this week!!! After I changed my jetting back to 48pilot, 152 main, and ncvt needle on the 4th the bike was so crisp and super snappy!!! The garggle was even gone. I just got ass backwards on the idle and that screwed me!!

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What elevation do you ride,and what year is your bike,I have a 07 which i would like to re jet,Thanks

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I have an 07, but I'm still trying to fine tune my jetting. I ride 800-1300'. I'm really close, but learning myself. I've only had this bike for a couple of months and have been doing the free mods and jetting myself. Its been a bit of a learning process but I'm almost there. I just got a new needle that I'm trying to dial in. The 48 pilot is perfect for my bike as is the 152 main, super crisp, Its just this needle area of the throttle I'm having trouble with. I've only tried 2 positions so far and its been to rich at 1/4 throttle only. Just barley a little spot of richness. I cant work it out w/ the fuel screw, so I'm gonna try a leaner position. Finally got my needle tool in yesterday, so tomorrow I'll pull it again and try a different clip position since it w/ be easier and faster to remove :bonk:

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Jetting done properly(first time you try for yourself) can be both maddening and extremely satisfying. Once you figure out what works(or doesn't) for a given combo of conditions, will give you insight should a problem arise in the future. Knowing you should change a pilot,main,clip position,leak jet ,etc. will come to you almost naturally, if you play with it enough. Once you think you have a perfect setup, try a different needle , do a o-ring mod on the accel pump,change a leak jet, use what works and make note of it, also make notes on what doesn't work. Jot down riding impressions based on temp,humidity ,altitude,etc. When you get some experience help us out! LOL!

Edited by papawhiskey1

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Hahaha!!! Yea next I may replace the leak to 50 since I know where it is now. One thing I did wanna do is adjust the linkage. When I had my sub frame up I was twisting the throttle and watch where it was shooting onto the carb. It was kinda hitting the lower right-side of the carb way in the back. So I know it could be adjusted just alittle bit to the left, but I dont know how to adjust it and when I had it apart no one responded to my question!!! LOL.

Oh yea, and the hardest part about jetting isn't tryng to figure out what combo of jets are needed, its tryn to reattach the airbox boot to the carb!!!! &%$#@!?!! :lol: I had to grease it and my buddy and I spent 30 min tryn to reconnect it!! The 1st time I did it I got lucky, greased it and it slide right on w/ 1 lil finagle!! If anyone knows the trick, PLEASE let me know. I'm scared to take it apart again just because I don't wanna deal w/ that!! Lmao!!! :bonk::lol: :lol:

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Retime and redirect your accel pump squirt if possible(Krannie may have some insight). Other posts will have more info than I do since I haven"t encountered that particular problem yet. My recommendations are 1 Good lighting. 2 patience 3 six pack of favorite adult beverage 4 a little air filter grease at the carb throat helps (as do Asian sized fingers) on getting the boot back on. 5 Make sure your clamp is round(easy to deform when pulling airbox).(see # 3 if all else fails).

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If anyone knows the trick, PLEASE let me know. I'm scared to take it apart again just because I don't wanna deal w/ that!! Lmao!!! :bonk::lol: :lol:

Light coating of grease AND put the clamp on so it is just snug. This forces the boot to stay round.

Lower the sub-frame so the boot touches the carb, add just a touch more pressure, and wiggle the carb back and forth a little. Should pop right on.

And BTW, everything can be changed without lifting the sub-frame. Just loosen the clamps on the carb and twist it. You may have to loosen some cable ties to get slack on some of the cables or the TPS wire, but you can do it.

Also, it helps to replace the float bowl screws with allen head sockets.

Jim.

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Thanks Jim. I did change out all the screws w/ allen bolts when I 1st got the bike and installed the new fuel screw. When I change out the pilot and main I always loosen it, twist it and barley get them changed from the bottom. Its easy to do the main, but the pilot is always a bit tougher. It seems that I can only get it turned just a little even after loosening some hoses, ties straps, stuff like that, but it is enough to get it done. The one thing you said that I haven't done is making the clamp snug when putting the boot back on. I bet that makes a big difference now that I think about it. I use the grease, I work the carb, but I've haven't had the clamp snug enough!

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Is your idle better now?

I see so many people that seem to want to make a simple job complicated.

If you put a 45 pilot at 2.0 turns out in a 250X or 450X, you will never have to touch it again. The dyno comfirms that over and over and over and over.

A 48 starts better, but is too rich after it is warm, unless you turn it to 1.5 turns out, in which case you are adapting for an over-rich condition.

I know there are procedures about how to confirm your pilot settings, but they all get back to a 45, at 2.0. Maybe 1.75. See how close that is?

So many smart people on this forum have taken all of the guess work out of jetting.

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<<If you put a 45 pilot at 2.0 turns out in a 250X or 450X, you will never have to touch it again. The dyno comfirms that over and over and over and over.>>

Only for a given set of conditions. If you check the stickies at the top of the forum, you will see that there are many that use a 42 and some that use a 45.

The JD Jetting kit for the 250x comes with a 42 and your supposed to set it at 1 3/4 turns out. Their instructions also state "The fuel screw may need to be readjusted to get a steady idle and crisp response".

So even those who have dyno tested to the ends of the earth are saying that some adjustment is necessary.

Jim.

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I will agree that some adjustment can be done, for those with a terminal case of fiddle-itis.

I can think of no circumstance where a 45/2.0 setting won't allow any bike to start, run, and idle well, and allow the tuner to rule out improper jetting as a starting point for diagnosing other driveability issues.

One local dealer here delivers their WR450's with a 48 pilot, knowing that a 45 is correct. Their logic, and it is probably true, is that a 48 starts and idles better cold, and results in less hard starting complaints.

I don't care what other people use, and it's fun to talk about, but my point is that we are taking the simplest of tasks and turning into something so complicated that even the government would be proud.

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I will agree that some adjustment can be done, for those with a terminal case of fiddle-itis.

Hum, well I think Honda engineers would disagree with you. The procedure I posted in response to a question from someone who wants their bike to run as well as possible is the same one that is outlined in the Honda OEM service manual. In fact if you have a PAIR valve, it's even a little more complicated.

If you took your bike in for service, it would be the same procedure the dealer would perform.

You may not care if your bike runs as well as it can, but there are those who and some enjoy wrenching just as much as the riding.

Jim.

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The bikes I ride are finely tuned. The OP states that he can't get to a starting point, in order to get the bike to run well enough to set his idle speed.

My quoted line up there say that I agree that some adjusting can be done. The Honda engineers dissagree with that?

My point is for those who lose sleep about pilot jets, there is a setting available that will get you so close that it could be considered a "set it and forget it" position for normal operating temperatures.

I have dyno'd these bikes and measured different settings on Eddie Sisneros' dyno, and have a pretty good feel for what works. YMMV

Edited by Leardriver

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Colorado is much different (altitude) than Georgia. Goonsquad is liking the 48 pilot,as I am in Alabama!

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