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mboyer

Tuning issues

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Have a beautiful 2004 E. Bought a parted out 2001 frame and title and use that you street it. Nasty divorce led to bike sitting around for five years. Cleaned out carb and still having problems. Somehow I ended up with completely wrong main jet..see pic. It's been so long that I don't remember if I ever had it right after installing the exhaust system.

Anyhow...I'm so confused with how to tune it and I'm really good at tuning engines!? The main jet, pilot jet, air jet, main air jet, what the hell...is this thing a Lamborghini? What happened to idle screw and high speed screw? And whoever designed the adjustment screw that goes through the float bowl should be publicly executed by hanging.

I bought the bike brand new in I'm guessing 2006, it came with fcr 39 carb. I put full FMF power core system with power bomb header and JD jet kit. I've got the new needle at 5th groove as per instructions.

The two you can see under the drain plug:

Tall one 162

Main jet(I think?) 165

The two jets under the removable plenum thing are stock 60 and 200.

Coast enrichener is on. The two o rings that hold the plastic elbows held on by the wire thing are questionable. I think they're good but can't find perfect replacement o rings.

I accidentally somehow had a 165 main jet in it. And I've read posts about glowing red header pipes. Let me add this...with the 165 main jet in there, the head pipe would glow red writin 2 minutes. It's not normal and air flow across the pipe isn't the answer..in my opinion.

Current problems:

1) I can't figure out what all the different jets are and what they are responsible for.

2) I'm experiencing hanging idle. Part of it is throttle cable frayed right where it goes into the shield from the wheel on the carb but that's not all of it. I definitely have something wrong in the tune.

I need a new fuel crew for sure. I'm getting fast with getting the carb off, even the air box boot, no problem. The first few times...what a pain!

Eddie posted that if the fuel screw tunes correctly at between 2 and 3 (I think?) turns then the tall jet under the drain plug is correct.

Help!!

I'm trying to download a YouTube video of the bike....Screenshot_20181004-141806_Gallery.jpeg20181004_130739.jpeg20181004_130746.jpeg20181004_130854.jpeg20181004_135422.jpeg20181004_140139.jpegScreenshot_20181004-141806_Gallery.jpeg

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Main jet has very little to do with idle speed. If you have a hanging idle and glowing header that is likely due to a clogged pilot jet or passage. Replace the jet with a new 45. Could also be an airleak creating a lean situation.

I any case, despite all the jetting threads you read the bike is actually simple and forgiving to jet. The people that struggle have an underlying issue that they don't realize.

 

 

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Main jet has very little to do with idle speed. If you have a hanging idle and glowing header that is likely due to a clogged pilot jet or passage. Replace the jet with a new 45. Could also be an airleak creating a lean situation.
I any case, despite all the jetting threads you read the bike is actually simple and forgiving to jet. The people that struggle have an underlying issue that they don't realize.
 
 
Glowing header was remedied by changing to 140 main jet. Hanging idle is the only issue now. I'll see if I have a new 45 and try that. Thank you:)

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10 minutes ago, mboyer said:
54 minutes ago, ohiodrz400sm said:
Main jet has very little to do with idle speed. If you have a hanging idle and glowing header that is likely due to a clogged pilot jet or passage. Replace the jet with a new 45. Could also be an airleak creating a lean situation.
I any case, despite all the jetting threads you read the bike is actually simple and forgiving to jet. The people that struggle have an underlying issue that they don't realize.
 
 

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Glowing header was remedied by changing to 140 main jet. Hanging idle is the only issue now. I'll see if I have a new 45 and try that. Thank you:)

Main jet is responsible for wide open throttle.  It has nothing to do with the header glow.  Any change that occurred when you switched jet is coincidental.

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Main jet is responsible for wide open throttle.  It has nothing to do with the header glow.  Any change that occurred when you switched jet is coincidental.
Quite a coincidence, don't you think? Did you see the picture of the two jets next to each other? Huge difference in size. For that swap to have solved the glowing header issue, which I still believe is true, would mean that the main jet flows fuel not air. I'm guessing that's true?
The only way that wasn't the solution is if the main jet does absolutely nothing until it's at wot.
Does the main jet do absolutely nothing until it's at wot?

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My mistake, the starter jet (according to the micro fiche part #28) was 165 and I changed it to 140 which solved the glowing header issue. Sorry!

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My mistake, the starter jet (according to the micro fiche part #28) was 165 and I changed it to 140 which solved the glowing header issue. Sorry!
You're still confused. Starter jet should be something small around a 65. It's purpose is to control fuel when the choke is active.

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Main jet has very little to do with idle speed. If you have a hanging idle and glowing header that is likely due to a clogged pilot jet or passage. Replace the jet with a new 45. Could also be an airleak creating a lean situation.
I any case, despite all the jetting threads you read the bike is actually simple and forgiving to jet. The people that struggle have an underlying issue that they don't realize.
 
 
I received the longer fuel screw today and realized that I didn't have an o ring on the stock one! I'm sharp as a marble.
Thank you for your assistance. Will update after I get it running tomorrow.
It's funny..I use to hate taking the carb off..the air box boot, throttle cables, etc..I could probably do it in 5 minutes in my sleep now.

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Still hanging. Doesn't really need choke to start so I'm guessing it's rich? Should I try moving the needle..if yes do it lower the needle or raise it? I've read a few threads and am confused because to lower the needle you raise the clip position and it's not clear which way to go. If the needle meters fuel then I lower it to lean out. Also..fuel screw position doesn't seem to matter on how it idles. Still runs like a monster, just has hanging and inconsistent idle. Please help!! Thank you:)

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Have the same bike ,  only difference is yoshi full system rather than FMF rather .

Here's my 2 c worth based on my experience:

1. You mentioned frayed throttle cable - replace these as first step if not already done.

2. Agree with the guys above that the hanging idle and glowing header are not related to the main jet size

3. Remove and clean out the carb/ all jets if not already done - and replace the accelerator pump diaphragm while you are at it - if the bike has been sitting that long at least after doing this you are starting from what should be a good base

4. If you still have hanging idle then check for air leaks at carb boots at where the air filter mates to the air box

Hope this solves the hanging idle ....post again if it doesn't

5.  Re main jet - the 140 is too small. Here is my set up:

Full Yoshi RS 3 system

 K and N air filter

Air box lid and snorkel removed 

160 main jet..... (not stock)
200 main air jet (stock on Aussie E)
100 pilot air jet ..(stock on Aussie E)
EMN needle clip 3 (or you can  use your stock DXP needle clip 5)
45 pilot jet..(stock on Aussie E)
2.25 turns fuel screw

This should be a good base set up for your E. Even the stock 165 main runs ok.

Hope we can help you get the bike running....

There are plenty of people on this forum much more experienced than me ...I have found following their advice has saved me a lot of time and money!

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Check for air leaks between the carb and head. The needle has nothing to do with idle.

Edited by JoeRC51

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