2001 400E A little carburator help please

I couldn't leave my new 2001 400-E alone. Several people have sent messages and made comments about my alleged 138 main jet being to small. Since the dealer put it in before I had a chance to ride it I had nothing to compare it to. You guys talk about lifting the front wheel being easy and I felt I had to work a little to hard at it.

Anyway, I pulled the plug and it was whiter than a brand new pare of underware!!!dahhhhhhhh So much for trusting the dealer. They did give me the stock 142 main jet so I figured I would see what they had done to me. After looking threw the archives I decided what the hell and got after it. What a pain! It is hard to believe that enlarging the air box opening would help when the air still has to squeese through that little slot to get around the shock!

I found the needle clip in the middle groove, three above and three below. I left it alone. It did indeed have a 138 main jet and the screw on the bottom was 1 1/2 turns out. I have a set of propane orfice drills (really nice) so I compared the 138 to the 142 and there is .004 difference. I went to my next drill size up which was .006 bigger than the 142 and drilled out the 138 and saved the stock 142. I ajusted the pilot screw out 2 1/2 turns and put it back together leaving the snorkel off the air box as before. I plan on leaving the exhaust stock. I hope my plug color becomes normal. I never heard any pinging or backfiring and I thought it was running great. Can someone tell me the scoop on the needle rod moving the clip which way to rich and lean. What is it for? Midrange or transition from idle to main? I live at 5,000 ft so I didn't want to go overboard on the jeting. I started it in the garage and it wasn't as cold blooded as before. I only have about 500 miles on her. Most of the time I was on and off the gas trail riding but the last time out I ran it about 5 miles at 70mph then loaded it on the trailer. Thats why I figured the plug reading would be ok for the main. Did I miss anything?

What altitude are you at. If you are near sea level put in a 165 main jet and 48 pilot. Raise the needle by lowering the clip. This richens the mid range. Also remove the airbox lid. The stock 142 main is good for a bone stock bike with the airbox lid on. Remove the lid and it is going to run lean.


[ December 16, 2001: Message edited by: perryg114 ]

From what I'ce read the needle clip is for 1/5 throtle to about 3/4 throtle. There is some overlap for the fuel screw {idle to just past 1/5}and for the main jet{ before 3/4 to wide open}. If you raise the needle by lowering the clip you will enrichen your mixture. If you lower the needle by raising the clip you will make the mixture leaner.

I run a 160 main at sea level with snorkle removed and exhaust cap drilled with baffles drilled out. It's a tad rich but it works well. My needle is raised all the way up as well as out 2 turns on the fuel screw.

Hope this helps.

If 3/4 throttle and up is main jet, 1/5 to 3/4 throttle is needle, and 0 to 1/5 trottle is fuel screw........what is the pilot jet for?

ok I think I understand. The needle contorls midrange and the farther down the clip the richer it is.

5,000 ft. Colorado

Snorkel off air box

needle in the middle for now

I think my main jet ended up about 145

The screw on the bottom out 2 1/2

stock exhaust

watch my plug

This has got to be a improvement I think I should have gone down one on the needle.

I would only be guessing about the pilot air jet. I don't know what it affects.....Anyone?

I dynoed my DRZe in Denver @ 5280ft.

Stock pipe but wraped with exhaust insulation.

Stock air box with a K&N. Lid (snorkel) removed

Enriching circuit(smog thing on side of carb removed. See Stroker kit threads.

#100 Pilot Air Jet. ( Intake side of the carb in front of the slide see Stroker Kit.)

#50 Pilot Jet (float bowl)

DVR needle 5th position (Stroker Kit) stock needle try 4th position from top.

#142 Main Jet (float bowl)

Fuel Screw 2 1/2 turns out.( In front of float bowl)

Made just short of 34 HP., runs great starts great.

Works at Rampart Range Colo.

Food for thought: With the efficiency of todays 4-stroke combustion chambers unless the jetting is way rich it takes forever to get any color on a spark plug that is correctly jetted. A dyno with a O2 sensor is the best way to jet the bike or at least get a base line to work from. There should be very little color if any at all. The only place to show color will be on the threaded steel part that is exposed in the chamber and it will only color because it is not hot enough to burn clean ( Don't pay any attention to that area.)

even a correctly jetted GSXR will burn clean.

When I bought my bike the dealer had a #132 main in it, I'm glad I check things.

[ December 17, 2001: Message edited by: Hotler ]

the pilot jet is for 0 to 1/4 throttle.it also provides fuel for idle.the fuel screw controls idle mixture-clockwise(turning in)will lean the mixture,counterclockwise(unscrewing)will richen.this only affects the smallest of throttle openings.if you experience an off-idle stumble,or bog,then you can richen up the fuel screw until the problem dissapears.all circuits overlap,starting from 0 and going until wide open.in other words,at full throttle,your pilot,fuel screw and needle will still have a small effect

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