Carb needle spacer

[Rod.s]

This is what i read...if it is not related to trx carbs then maybe the mod is a good idea .

It's not a mod the factory carbs came with the steeped spacer.

[cobbadiggabuddyblooo]

That’s correct Rod.
I did the mod because it was an aftermarket spacer on Marko’s Bike.

[Ragnar]

This carb problem is commonly known in Germany. I attached a drawing with the exact measurements.
Stolen from the German forum‘s Download section.

https://ibb.co/hjVnWT

[devonnick]

Ah i must have aftermarket spacers in mine they do not have a cut away section I will alter mine as this seems to be correct ...thanks.

[HolerTogni]

Hi all!

As it is believed in the German forum, the original spacers do NOT have a cutaway section.

The inclined position of the needle resulting therefrom shall correct the position of the needle that otherwise would be inclined too much to the cylinderhead side (due to the downdraft type carb) and produce (iirc) a ring shaped gap with the emulsion tube. That is, what Adler850 said about three years ago.

It is also believed that there is no additional wear caused by the inclined position of the needle.

From my personal experience I can only say that the needles and the emulsion tubes wear out with use no matter if the spacers have this cutaway section or not and that the engine runs noticeable better with new needles and tubes.

The spacer shown above is usually additionally put in to equalize the support for the needle. Than, the clip usually can stay in the same position as without the additional spacer.

Spaced g r e e t i n g s from Munich!

[andrewo]

This is what i read...if it is not related to trx carbs then maybe the mod is a good idea .

It's not a mod the factory carbs came with the steeped spacer.

I ordered a needle kit from Yamaha as I wanted to put the standard Yamaha needles back in and noticed that the needle kit also includes new spacers, so I was surprised to find that the factory Yamaha spacers look exactly the same as the ones that were in my carbs; just round with no step. So whilst I'm convinced that you guys are right about having the step in the spacers (and from the drawing, they appear to be more D shaped), it seems either Yamaha have changed the shape of the spacers from the original ones used, or they only ever used the round spacers with no step.

I don't care which is correct, but just saying that the standard spacers in the Yamaha needle kit don't have a step, so if anyone orders a needle kit to get the factory spacers with a step, you'll just get round ones.

[cobbadiggabuddyblooo]

When you look at the part number does it finish with a -01 ???
Usually that denotes a revised part number . Most will finish with a -00

[OzzieDave]

I have just cut the step into my spacers, as I have been having problems with a hesitation at low throttle openings.
It seems to have cleared up the problem. I had fixed a number of air leaks and tried different pilot jet sizes, without any success, before trying it.
I have the clip on the needle in the middle position. Std pilot jet .45 now, std mainjet.

[andrewo]

When you look at the part number does it finish with a -01 ???
Usually that denotes a revised part number . Most will finish with a -00

Yeah Sorry Cobba. I took some photos and was going to post them but probably no point. I did mean to list the Yamaha P/N but missed that too.

It is #4NX-1490J-00.

I should have realised the 00 was original, as I've had a lot of XS parts suffixed with 01 and beyond, so these appear to be what should have been in the TRX carbs in the first place. I'll be grinding my original ones down as I've got new ones if I stuff them up. Will post back when I get around to doing them, which might be weeks away the way I'm going at the moment.

Just for some useless information, I actually just looked up one of my old Yamaha parts lists and the following was the case then and looks to be the same now for what they call General parts:-

AAA-BBBBB-CD-EE with

AAA being the Model code number
BBBBB being the Basic code number
C being the Design code number
D being the Design change code number
EE being the Colour code number it seems only for items with specific colours

There are also Standard parts which start with a "9" as such - 9xxxx-xxxxx
I guess this would all make sense to parts interpreters!

Andrew

[Dirk86]

Hello,
As this lowers the needle then what would be the good position of the needle does it have to be compensated with the circlip? And does anyone have experience by how much?
Regards Dirk

[OzzieDave]

I have cut the step in my spacers, then had to place the circlip in the bottom groove in the needle.

[Dirk86]

From what poisition did you move the middle? and it ran altight then?

[cobbadiggabuddyblooo]

I would suggest if you modify the spacer to start with the mixture lean and clip on the top of the needle so it lives as far as it can down into the main jet.
If you find hesitation lift the needle as it’s easy to access from the top.
If modifying without fitting a new kit place the clip in the same position and if not quite as responsive as before then lift the needle by 1

[Dirk86]

Im not fitting a new kit, i cleaned the carbs and renewed the original tubes and needle.
Because when i bought it it ran bad and with not mich power up to 3500-4000RPM, in higher rpm it ran good.

If i put the clip in the lowest position The needle is stil sitting lower a couple mm then it was without modifying the spacer when the e clip wad in the middle position.

What position of the needle should be good when only the spacers are modified?
Should the needle be raised with shims to match with previous position?
i have a standard k&n air filter and bos racing exhaust,

[cobbadiggabuddyblooo]

Bike wasn’t running good to start so start from lean mix (top clip) and work your way down the needle to you find a sweet spot.
Does it have the std ecu???