3en2 Needle help.

[dinodelta]

'89 3en2 in the UK. Presumed Japanese grey import as all the safety stickers are in Japanese.

I'm just pulling my carbs apart for their first clean and joy of joys, the first component I touch (the jet needle) has 5CFZ4 stamped on it. My workshop manual gives the needle ID as 5CFZ2 but I believe that is an American manual and they usually run everything lean.

Anyone know if the 5CFZ4 was a Japanese/ rest of the world fitting because I have it listed as the FZR600 needle? The bike seems standard all over, except for that needle and the ignition and throttle switches which match the '94 FZR600. The loom wasn't been chopped about and still had the 3en serial on it.

Also, if the needle is standard, what is the clip position.


Thanks

[Evilchicken0]

If this is a running bike then clean up the carbs and replace.
If it's a non runner then get the carbs as clean as you can and keep the settings as they are. The 600 3HE carbs are similar it's just the settings that are different.

You'll probably need to renew the airbox rubbers if they've gone hard. Get them from Fowlers in Bristol - ring them up, you'll need to quote your frame number before they'll serve you.

[dinodelta]

Right. Just stripped the carbs and they have the 35mm length emulsion tubes (needle jet) which FactoryPro say are in the FZR600. They give the length for the FZR400 tube as 30mm.
I have a Japanese 3EN2 parts fiche and that gives the emulsion tube part number as 3EN-14141-92, the FactoryPro 400 tube (American) is listed as 1WG-14141-90-00. The FZR600 part is 3EN-14141-90-00. That should mean the carbs are the same for the 3EN 400s and the early 600 as the part numbers are the same for the emulsion tubes. The 3EN part of the part code is the manufacturers code for the machine the part was originally introduced on. The 14141 is Yamaha code for a emulsion tube (needle jet) and the 90 or 92 on the end is usually an improvement code and the parts are usually interchangable .

My jets all match the Japanese parts fiche specs. Also my needle assembly looks more like the Japanese one.I'll list Japanese (import) and American jetting below.

American FZR400U and FZR400SUC '89

• Main Jet #87.5
• Pilot Air Jet #130
• Pilot Jet #15
• Jet Needle 5CFZ2

Japanese (import) FZR400R 3EN2 '89

• Main Jet #92.5 (Cyl #1 #4)
• Main Jet #90 (Cyl #2 #3)
• Pilot Air Jet #115
• Pilot Jet #35
• Jet Needle #Mine is running a 5CFZ4. Anyone know anything different?

So basically I thought I had 600 carbs on my bike due to the emulsion tube length but it seems that the Japanese domestic 400 (the 3EN2) shared it's carbs with the 600. I would like the pilot screw and jet needle serial if anyone knows it.

[Evilchicken0]

That's quite a technical question ....

As I said if you've got a non-runner then clean the carbs then see if it fires. If there's a specific problem with the carbs from a running bike then maybe let us know how it runs .... we can teel a lot more from that.

[dinodelta]

Just wanted to know what code was on the Japanese/rest of the world market bike not the american models.

My bike runs smoothly when its going and starts fine if you start it everyday but leave it for 3 or 4 days (on a battery conditioner) and it's a can of Easy Start to get it going. I just want to make sure everything is back to standard before anymore fault finding.

So far restored the EXUP with new seals/bearings and cables. The airbox is on and the inlet stubs are not leaking (though hopefully I'll be getting the tooling finished over Christmas to mould some new ones). The valves clearances were done (though none were more than .005 out). New plugs/leads/coils and battery. I cleaned the starter commutator off as it was about 2/3rds covered in carbon (meaning the engine might not have been cranking at full speed).
Stripped the carbs but still trying to confirm the standard Japanese 3EN2 specs. What is definite is the settings below:

• Main Jet #92.5 (Cyl #1 #4)
• Main Jet #90 (Cyl #2 #3)
• Pilot Air Jet #115
• Pilot Jet #35

Just need to know the standard needle code, clip position and needle jet.
Or a link to a Japanese (European?) workshop manual. I spent some time going around Yahoo.co.jp but haven't seen one yet, just that American manual everywhere.

[Flyingbroadyp]

Could you tell me what the settings are that you have for the needle position, mixture screw and float heights? I crashed my 3en2 about 11 years ago and after a slow rebuild I have it road legal again, however it's not running right and the carbs have been stripped and cleaned by 3 different people and still no joy. Can anyone help? My current settings are mixture screw out 3 turns, float heights are at 22mm and needle position is on the richest setting last tab closest to the point. The bike starts ok on choke but once up to running temp it it holds rpm at about 2-3000

[willandrip]

Needle clip position is 3rd groove.
Air screws are 2.5 turns.
Float heights; I use the fuel level method,4mm to 6mm below the line on the bowl casing.

You sound like you are running all settings rich.
Is it a very open pipe fitted ?

Non of the above should prevent the butterflies closing fully and raising the idle speed.

Are the correct cables fitted and adjusted?
Does the throttle snap shut to the idle ajustment screw ?
Make sure the choke slides return all the way back (the inner cable is easy kinked).
Have you tried this without the airbox on ?
The airbox interferes with the cable run on these and you have to faff with the cable routing and tensions to get an instantaneous closure of the butterflies.

You can hear and feel the throttle snapping shut.
I do not think that the sync. screws can be over adjusted in such a way as to make the idle screw adjuster redundant but it may pay to check.



Welcome in by the way; ( I always forget my manners )

[Maelstrom]

Hello,
The American bikes are 1WG. They never had a 400 with the BDST carbs that your bike has. Completely different, so no point in comparing them or reading American 400 manuals. The 600s also used the BDST that is why you will find similar parts, numbers and useful service information.

Emulsion tubes have different internal diameters. They are not all the same.
You have only quoted the needle number not the emulsion tube (also known as needle jet). There is a Mikuni number stamped on your emulsion tube. It is a letter-number combination. In my 3TJ1 they are X-6.
You can download a spreadsheet here of sizes for emulsion tubes and needles here.
www.mintelonline.de/Dokumente/Technik/V ... adeln.xls‎

cheers
Blair

[willandrip]

Blair; I think you are referring to a post thats 4 years old and the author long gone.
The 3EN2 setting I have just quoted are from the correct manual.
The new member has just tagged onto an old thread.

I have a measurement of 24.8mm in the Jap manual but I do not know what it refers to; (cannot read Jap characters)
Seems too precise for a float height.???
You may be able to work out what it is ??

Will post up pic. soon as batteries for cam. are charged.

[Maelstrom]

Thanks for that Mr Willandrip. I am always replying to dead posts.

Mr Flyingbroadyp, can we assume that you have replaced ALL of the carb seals?