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Hi to all .

I have a 93 Japan grey import in Greece (yes we are still alive and kickin)

and I looking to restore my carb. I have found this page for anyone who is intersted.

My problem is that they list models from 1999 to 2006.

For all the parts they show total compatibility to all years models, EXCEPT the main nozzle for the '99 model and all the others.

'99 model main nozzle

2000-2006 main nozzle

Does anyone know if there are any actual differences between these two parts?

And if they are ,which is the suitable for my '93 OE?

Is it all just the same? If so ,Im ordering the cheapestbiggrin

 



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For my '93 OE?

numero uno - 4RR-14341-00-00 NOZZLE MAIN

numero due - 4GY-14341-20-00 NOZZLE, MAIN JET

Anyone knows diferences ? or should I just buy the cheapest?



-- Edited by pantheman on Wednesday 27th of June 2012 11:14:18 PM

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huh?? the main jet nozzle does indeed hold the main jet, but the part numbers quoted by pantheman are both for the main jet nozzle (aka holder).

in 1999, nozzle had prefix 4RR but jet (#137) had prefix 4GY
in 2006, nozzle had prefix 4GY (with same number except -20- instead of -00-) and jet (#137) had prefix 4GY (with same number)

other posts somewhere in this forum, have detailed solving carb "stumbling" problems simply by using the older nozzle in the newer carb (!!). I think the nozzle may be noticeably physically different between the 1999 and later models.

So if the 1999 bike used to run OK once, then you should surely use the 4RR (ie correct 1999) nozzle/holder, if you think there is a need to replace the existing one for some reason.





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Whoops - sorry about that - more speed less haste! I have deleted my post to save any confusion. Well spotted Brindabella smile

I looked back at the Russian fiche for a 1996 TTR and it's also got the 4RR number - see http://www.megazip.ru/ru/bike/yamaha/view/1086/15363/191813#g191820

I have a couple of carbs in pieces so will get the nozzles out and see if I can spot the difference(s).

Interestingly, the "nozzle sets" (which include the needle) have the same part number from '96 through to '06. 

Brian



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I have been thinking about the different nozzles i.e.

1993-1999 model main nozzle - 4RR-14341-00-00 NOZZLE MAIN (V95)

2000-2006 main nozzle - 4GY-14341-20-00 NOZZLE, MAIN JET (V95G0)

and wonder if it explains why, in the UK, the older UK TTRs ran a 137 main jet compared to the blue TTRs’ 147 jet. They would have used the first of the two nozzles listed and I am thinking that you have to match the nozzle to the jet.

This may explain why my TTR325 runs so much better on the 137 jet as I am pretty sure that I used a carb from a metal-tanked white TTR.

Another name for the nozzle an emulsifier tube. The emulsifier tube is designed to help convert the fuel coming in to a fine mist. Yamaha carefully position holes in the tube to help aerate the fuel and get little tiny air bubbles to form to help make the fuel vaporise into a fine mist. The finer the fuel mist in the air flow the better the combustion is in the combustion chamber.

Brian

 

 



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..but looking at the US parts list, it seems that between 1999 and 2006, the only change was in 2000, and that consisted of a different emulsion tube plus a different jet shroud, which persisted to at least 2006.

Throughout that period, the slide, diaphragm, etc stayed constant, as did the pilot jet (#50) and the main jet (#137).
So in the US, the new emulsion tube did NOT require a new main jet.

In the Russian 1996 list, it seems that it is pretty much the same as US 1999, BUT they have the main jet as #147 (same as later European and Australian models). BTW, that list has a mistake in the main jet part number (14239 instead of 14329). The implication is that not only can the "new" emulsion tube work with the "old" main jet, but conversely the "old" emulsion tube can work with the "new" main jet! Who is to say which is the best though?

Interestingly (and relevant to the emulsion tube question) there is a post in  http://www.ttr250.com/carb_fix.htm  (with pictures) which details how putting the old parts in a newer carb on a standard bike gave an improvement!

To me, a question is, why did the US models run a #137 (for ALL US TTR variants in all years 1999-2006) when it seems that in other parts of the world (except older UK models??) a larger #147 main jet is standard? Maybe the US were more serious about emissions or noise or exhaust sparks and/or actually had a REAL restrictor in the system, even though those models were apparently not registerable for road use.

So jetting is a big puzzle.

Maybe those funny US TTR models are the source of the (mistaken??) belief that the TTR has to be jetted up and have its header, airbox and muffler modified to achieve "real" performance (and noise and placebo effect!). People even seem to believe that the throttle stop adjusting screw is some kind of evil attempt by Yamaha to limit the performance of their motorcycle. And attempts by owners to replace the jets with ones from different manufacturers (eg mikuni, with different numbering scheme) has probably lead to even more internet driven confusion. Plus so many old bikes have gummed up carb jets that ANY jet change would be for the better (although proper cleaning may be cheaper and more effective).

Having said that, I guess there must be some optimum tuning setup, but it is a balance of peak power versus part throttle power versus low rpm power versus noise versus fuel economy as affected by riding style and terrain and altitude and temperature. So I reckon we will never have agreement on what is best Anyone got any good dyno charts?




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Thank you for doing the proper research Brindabella!

I thought I had found "The Answer" to the 147 v 137 jetting conundrum so jumped to a conclusion much too quickly disbelief

So, as you say, the 147/137 jetting difference (which on the face of it is a big one!) explanation has still eluded us.

I have a feeling that, if the US models had a different restrictor to the rest of the world, we would have heard about that by now and it would be figuring large on a Thumper Talk thread under "free mods" and cutting CDi wires etc wink

Anyone else know any more about this?

Brian



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This is all pretty interesting & somewhat timely for me.

I bought my TTR a few weeks ago, not quite running, on the assumption that it was a gummed up carb (from storage) that was the problem, which turned out to be true.

The jets, pilot especially, were pretty clogged & while I got it going with the "cleaned" jets, I really needed to replace them. So I thought while I was at it, I'd change them out with the sizes specified (Mikuni sizes 140/52.5) in the Thumper Talk TTR threads.

Bike does run better, but still not right & I'm thinking now that I should have started with stock sizes to establish some sort of base line. But as pointed out above, what is stock?

I have to think the US spec is emmisions related. I wonder why the TTalk guys didn't just adopt or at least try, the euro-spec sizing? Or maybe they did & I just didn't see it.

At this point, mine kind of blats out in the hi revs if aggresively running through the gears, low end seems pretty good. Haven't checked the fuel screw o-ring & didn't (yet) replace the diaphram.

I would think after the jets/maintube that the needle (different taper?) would be the next variable for fuel delivery?



-- Edited by TDVT on Tuesday 26th of June 2012 11:13:44 AM

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So if I got it right ,I should order the 4-RR for my 93 OE , right?



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Although the article is written ref a 2-smoke KDX200, there is some useful info here to explain how carbs work.

I copied the following from it and would acknowledge Canadain Dave's work on it.

The Parts- No jet acts independently of the others but rather they work together to deliver gasoline to the engine. They do however target specific throttle openings and have the most effect is that area. See below.

The air screw is most effective between idle through 1/8 throttle.

The pilot (slow) jet is most effective between 1/8 through 1/4 throttle.

The slide valve is most effective between 1/8 through 1/2 throttle

The jet needle is most effective between 1/4 through 3/4 throttle.

The main jet is most effective between 3/4 through wide-open throttle.

graph.jpg



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Just had a look at my parts catalogue.

4 different part numbers are given for carbs for the white TTRs!

I haven't checked whether the part numbers listed are still current.

Main jets:

Model 4GY1 up to frame number 008400 - 142

4GY1 (from 008401), 4RR1, 4RR2 - 147

4GY3 (Raid), 4GY5 (Raid), 4WA1 (Raid) - 145

Nozzles:

4GY1 and 4GY3 use 4GY-14341-00

4GY5, 4RR1, 4RR2 AND 4WA1 use 4RR-13341-00

Only one version of the petrol baffle is shown - 4GY-14153-00

Pilot jets:

4GY1, 4GY3 use 43F-14342-24

4GY5, 4RR1, 4RR2, 4WA1 use 43F-14342-25

All the other carb parts are common for all the models.

Brian



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I thought I would add my findings to this thread...

The late blue model carburetors use the V95G0 main jet nozzle which is longer than the early pre-1999 models which use a V05 nozzle. This explains why there is two slightly different float height settings.

The petrol baffle is the same in both carbs.

I am going to fit an 0-ring (for the first time) to the older V05 main jet nozzle and see how it goes.

The older fuel nozzle is on the left side of the pic below (with the O-ring fitted).

009.JPG

I will upload my finding after a test ride.

Jarrah



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UPDATE....

I did not think that my bike could be any better, after fitting the main jet nozzle 0-ring and the main nozzle from ''my old'' 1994 OE 4GY model, I have a new favourite bike for trails awwawwaww I don't think I could go any faster on my WR400 (without killing myself lol).

I think fitting the old nozzle did the most for performance but the O-ring must have helped to ''smooth it out''.

I LOVE THIS BIKE! awwawwawwaww

Jarrah



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I confess that I have no recollection of ever seeing an O ring on the nozzle and I have stripped many TTR carbs - where they there and I just didn't notice or do they disintegrate over time?

Must have a look at my "new" carb to check for O ringiness wink

Brian



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TTRfan wrote:

I confess that I have no recollection of ever seeing an O ring on the nozzle and I have stripped many TTR carbs - where they there and I just didn't notice or do they disintegrate over time?

Must have a look at my "new" carb to check for O ringiness wink

Brian


 Out of the two carbs that I have, neither had an O-ring or even a sign of one??? They must disintegrate quickly!

I used rubber grease on mine, applied with fingers crossed lol (it was only 10c). wink

Jarrah

 



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Main jet emulsifiers or nozzles.jpg

I was just stripping out a carb for cleaning and was surprised to find the emulsion tube was bent - how could that have happened confuse

I was looking through my carb spares and came across an old (slightly corroded - weird - how does petrol do that to brass?) tube and saw that it was shorter then remembered this thread! See pic above. The V95G0 is on the left and the V05 on the right.

I guess we are no further forward in explaining the differences in the carbs. Not sure about using that old nozzle so had better buy a new one I guess cry

Brian



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Diddn't diffrent years have diffrent length main jets ?
put a short main jet in the long one / long main jet in the short one
they may end up the same length...

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petenz wrote:

Diddn't diffrent years have diffrent length main jets ?
put a short main jet in the long one / long main jet in the short one
they may end up the same length...


 The main jet is still the same size and thread pitch, but the nozzle is different. This is why there is two different float heights between Open Enduro models v's 1999 blue models.

IMO- the shorter VO5 Open endure nozzle giving more throttle response and better on rough, rugged sections as there is less fuel slosh.



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If you install the shorter OE nozzel will you have to change the float height?


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yamaha42 wrote:

If you install the shorter OE nozzle will you have to change the float height?


As an experiment, take off the float bowl and put some plasticine or similar in the bottom. Replace the float and take it off again and see from the thickness of plasticine under the main jet how close it is to the recessed bottom of the float chamber.

My guess it is very close (it was on a later carb I tried earlier) which makes me wonder about float heights as surely the main jet must be about an inch below the top of the petrol in the float bowl whichever nozzle is used - or am I barking up the wrong tree confuse

Brian



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yamaha42 wrote:

If you install the shorter OE nozzel will you have to change the float height?


 Not really, it still runs great without adjusting the fuel height.

Jarrah



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TTRfan wrote:
yamaha42 wrote:

If you install the shorter OE nozzle will you have to change the float height?


As an experiment, take off the float bowl and put some plasticine or similar in the bottom. Replace the float and take it off again and see from the thickness of plasticine under the main jet how close it is to the recessed bottom of the float chamber.

My guess it is very close (it was on a later carb I tried earlier) which makes me wonder about float heights as surely the main jet must be about an inch below the top of the petrol in the float bowl whichever nozzle is used - or am I barking up the wrong tree confuse

Brian


 Measured the float bowls, result- both the same...

You are correct by saying that the 1999-2013 main nozzle sits very close to the bottom of the float bowl (in the recessed chamber).

Carb body to end of main jet= 40mm

Depth of float bowl= 43mm

This only leaves 3mm for fuel flow (if using aftermarket Sigma jets only 2mm [not sure about Mikuni jets]). This also verifies why my bike runs better with the shorter main nozzle as the main jet has more clearance. 

As to the difference between main nozzles, I have not measured yet but the earlier VO5 main nozzle is the shorter of the two.

I have not found a decent Open Enduro manual to check the spec, but I know the float heights are different. My assumption is that the Open Enduro models need a higher float level to accommodate the shorter main nozzle, but as I have said, I am unsure where to download the Open Enduro manual to verify this. 

Will do more investigation when I have time.

Enjoy!

Jarrah



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Partzilla doesn't have the short nozzles from the OE bikes cry

As for the Mikuni jets, they are taller than the stock  HEX jets, however the slits for a flathead screwdriver are about the same height as a standard jet. Maybe I should just get yammi jets from partzilla then. 



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This page is from the workshop manual for a 1993 OE model 4MR. Shows the float height as 36.5 to 38.5mm

Carb page - white TT250RF 1993 4MR-AE1.jpg

The following page is from a workshop manual for a 1999 American (possibly Californian?) model TTR250L(C). Shows the float height as 26.5 to 27.5mm

Carb page - blue TTR250L(C) 1999.jpg

Although the blue model page shows the jet as 137, my guess is that the European model with the 147 jet would have the same float level. Why wouldn't it?

The earlier V05 nozzle is 50mm compared to the later nozzle's 52.90mm which doesn't explain a 10mm difference in float height confuse

We are missing something here. There must be another difference between the older and newer carbs - maybe in the carb body? I can't check part numbers as the bodies aren't available separately - only as a complete carb cry

Interesting that the 147 jetted carb has a 48 pilot whilst the 137 carb has a 52 pilot.

The great TTR carb mystery continues hmm

Brian



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Now just because you are running at full throttle on main jet..the pilot jet is still surplying fuel..
So if you have a lean pilot jet #48 you would need a richer main jet #147
if you have a rich pilot #52 you would need a lean main jet #137
but the combined fuel being surplyed from each combination is the same..
So why diffrent pilot jets... starting / idleing / slow running issues in diffrent climates ?




-- Edited by petenz on Wednesday 14th of August 2013 08:39:40 AM

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You could be right Pete but my guess is emission regs in different countries might also affect jetting and float levels.

What I only just noticed is that the fuel level is the same for both nozzles - so how does that relate to float height differences confuse

Even more baffled now coz its the fuel level that's important to the jet/nozzle height surely hmm



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I agree with petenz that the jets might "add up" the same (assuming consistent flow based numbering scheme).

and yes, emission regulations are a likely reason for the differences.
Also, I believe that some years back, Yamaha Australia was a "groomed customer" and gave feedback to the factory on jetting and suspension settings, which may have been used for certain markets.

the fuel level (same in both cases) is obviously the critical measurement.
to explain the differing "float height" measurements which yield the same fuel level:
(a) a printing error?
(b) different float shape or material density

BTW I did some "back of envelope" calculations which can help in mentally visualising the carb internal workings:

at a highway speed, throttle nearly fully open, I guesstimate that the amount of fuel sucked into the engine in the intake stroke (which would take about 4 milliseconds (half a rev), followed by 12 milliseconds until the next intake, would be equivalent to a spherical drop a little less than 4mm in diameter. (so I don't think much clearance would be needed to flow it into the main jet).

in this time, the column of fuel around the needle has to be lifted up into the venturi and the fuel level inside the emulsion tube will begin to drop but more fuel will be more sucked through the main jet. if the longer tube is being used, I guess towards the end of the intake stroke the fuel will have to be lifted a bit higher by vacuum working against gravity, so marginally less fuel will flow.

I guess some fuel sits around between intake strokes in the area between the aluminium column that the emulsion tube screws into and the emulsion tube (ie the part which I think, but don't know, is connected to higher pressure air somewhere). So I am assuming that for a fair portion of the intake, that drop of fuel is coming through the emulsion tube holes. But I might have the wrong picture here - please correct me.

The differences are kind of interesting, but a bit academic. I accept Jarrah's observation that in practice the 2 different emulsion tubes deliver approximately the same results, performance wise.







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TTRfan wrote:

Main jet emulsifiers or nozzles.jpg

I was just stripping out a carb for cleaning and was surprised to find the emulsion tube was bent - how could that have happened confuse

I was looking through my carb spares and came across an old (slightly corroded - weird - how does petrol do that to brass?) tube and saw that it was shorter then remembered this thread! See pic above. The V95G0 is on the left and the V05 on the right.

I guess we are no further forward in explaining the differences in the carbs. Not sure about using that old nozzle so had better buy a new one I guess cry

Brian


 Is the damage caused by cavitation perhaps?

 

Peter



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Sorry for asking but what's an emulsion tube? is it the part of the nozzle with the holes in it?

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yamaha42 wrote:


Sorry for asking but what's an emulsion tube? is it the part of the nozzle with the holes in it?


 It is the main nozzle, the main nozzle and emulsion tube is the same thing.

 



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yep, that's right - just for fun, go to google image search and type any of the following into the search box:
main jet holder
needle jet
main nozzle
emulsion tube
and you will see heaps of pictures just like the ones in this thread.

by the way I think I misrepresented Jarrah in my post above - actually he had discovered that the older shorter nozzle gave better performance for him, and the float level did not have to be adjusted. I have a hazy idea that Lin may have also discovered the same difference in a post somewhere in the history of this forum (but I didn't check).

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brindabella wrote:



 by the way I think I misrepresented Jarrah in my post above - actually he had discovered that the older shorter nozzle gave better performance for him, and the float level did not have to be adjusted. I have a hazy idea that Lin may have also discovered the same difference in a post somewhere in the history of this forum (but I didn't check).


 Correct! I didn't want to correct you as it may have confused things.



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Hello chaps.

I'm loving this thread. I just got back from the Pyrenees thing with Austin Vince and my carb was really playing up. Altitude maybe. The plug was fairly black and a clean out and a new plug made it better the second day, but far from perfect. I was a bit peeved to go all that way and have it play up, but it was wonderful, so I decided to go again next year and resolved to sort the carburetion and go armed as next year's one is even higher.

First off I found these people,
www.nrp-carbs.co.uk/shop/
And they sent me a float valve set, Various mains, various pilots, an accelerator pump and a float bowl gasket for TTR's TK carb. Next post, from stock. Some of the bits are oem and the whole bill was about 70 quid, but the pump was the priciest bit and they sent it to work. Something Fowlers will annoyingly not do.

Looking at Brian's two pages from the manuals it's obvious that something doesn't compute. They don't even get the imperial conversion the same twice so I think it's safe to assume that there's a miss print somewhere. It happens. You should see my Cagiva manual.

I'm going to fit it back on this afternoon so I have no results at present, but in my box of carb bits also lurks a spare XT660 carb as that's what's in my Skorpion. Emulsion tube is the same as the early model TTR one except it's marked V00, not V05 like the one from my (early) spare TTR carb. And it has an O-ring. The tube from My 06 TTR is the longer V95G0 marked item. I'll try and get a photo up at some point. I would never have spotted the difference were it not for your efforts. Float valve sets look identical too but I don't know for sure. (By the way, the little plastic grit filter on the back of the valve seat causes no end of problems on the 660 motor applications and people often bin it and use an inline filter in the fuel pipe.)

My understanding of the Bernoulli principle is sketchy but I think it's all about differences in pressure. A beautiful application of physics. (There ain't half been some clever B's) The main difference is the one created by the venturi in the carb throat which atomises the fuel, but I'm guessing the fuel 'pressure' will be affected by the depth of the jet in the fuel. I recently watched Das Boot. Great film.) As the later jet is 'deeper' it may experience greater pressure, and yet the pilot jet is still at the same depth on both carbs, so maybe this explains the difference in the relationship between the mains and the pilots in the two set ups. It also makes me think the fuel height measurement in the two set ups should be different. (Not as stated in Brian's two manual pages.) They offer different float height specs, But 10mm difference! ?? Whatever, a different float height spec should certainly require a different fuel height spec in my mind.

My bike was running rich so I'm going to try a lower fuel height (greater distance below the mating surface) with all my new bits and see what happens.

I will put together a little post about the VINCE. It was very good and Trish suggested the idea when I got my final bits before departure.

Andy


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Well, I've had it apart and put the parts in. Runs much better but I'm pretty sure it was simply the float valve that was playing up. Couldn't see anything wrong with the other one but doing the fuel height was much easier. Hmmm. I shall take the advice to refrain from using carb cleaner more seriously. That's the only thing I can think of. I don't think the black bits of carbs like it.

I did put the fuel height at just over 10mm but I think I'll put it back to 8-9mm. Feels like it might be a bit lean now. While I was in there it was obvious that the 38mm float height has to be wrong. There isn't enough room and the float tang would be very bent.

By the way, here's a pic of the emulsion tubes.ADR_1342.jpg

Left to right is XT660, early spare, and the one from my blue '06.

I put an o-ring on the longer one when I refitted it with a 147 jet in it. I figured it can't do any harm.



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To clear some confusion up, I did a parts cross reference using these two sites for reference- http://www.megazip.ru/ru/bike/yamaha/view/1086/2710/51744#g51751 and http://www.partzilla.com/parts/search/Yamaha/Motorcycle/1999/TTR250LC/CARBURETOR/parts.html

 
To simplify this I have used colour codes below to verify what parts go with what carburettor-
Carburettor
There is 5 different part numbers for the Teikei Y20P/1 (so far). Different countries may have different carburettor part numbers and nozzles/fuel baffles in the same years as listed also so keep that in mind. The part numbers are listed below-
The older 4GY-14301-00-00 version will be marked as red.
The newer 4GY-14301-22-00 version will be marked as dark blue.
The newer4GY-14301-24-00 version will be marked as green.
The newer 5GF-14301-00-00 version will be marked as maroon
The newest 5GF-14301-01-00 version will be marked as silver
 
Nozzle 
There is 3 different types of nozzles that are fitted to TTR250's.
If the main nozzle is the older version, part number 4GY-14341-00-00 it will be marked as red
If the main nozzle is the newer version, part number 4GY-14341-20-00 it will be marked as blue
If the main nozzle is the newest version, part number 4RR-14341-00-00 it will be marked as green
 
Main jet washer/fuel baffle
There are two different fuel baffles fitted to TTR250's (so far). 
The older version, part number 4GY-14153-00-00 will be marked as red
The newer version, part number 4GY-14153-01-00 will be marked as blue
 
 Model: 4GY1, year: 1993, colour: Purplish white solid 1 (0206); region: Japan (pink seat, white bike)
Carburettor: 4GY-14301-00-00
Nozzle: 4GY-14341-00-00
Washer main jet: 4GY-14153-00-00
Pilot:  43F-14342-24-00 (#48) and a #50 (according to the Yamaha parts diagram)
Main: 4GY-14329-74-00 (#147) and a288-14329-71-00 (#142)
.........................................
Model: 4GY1, year: 1993, colour: Purplish white solid 1 (0206); region: Japan (purple seat).
Carburettor: 4GY-14301-00-00
Nozzle: 4GY-14341-00-00
Washer main jet: 4GY-14153-00-00
Pilot: 43F-14342-24-00 (#48) and a #50 (according to the Yamaha parts diagram)
Main: 288-14329-71-00 (#142) and a 4GY-14329-74-00 (#147)

Model: 4RR1, year: 1995, colour: Purplish white solid 1 (0206); region: Japan (red, seat white bike)
Carburettor: 4GY-14301-24-00
Nozzle: 4GY-14341-20-00
Washer main jet: 4GY-14153-01-00
Pilot: 43F-14342-25-00 JET,PILOT(#50)
Main: 4GY-14329-74-00 (#147)

Model: 4RR1, year: 1995, colour: Purplish white solid 1 (0206); region: Japan ( purple seat, white)
Carburettor: 4GY-14301-24-00
Nozzle: 4GY-14341-20-00
Washer main jet: (part 8) 4GY-14153-01-00
Pilot: 43F-14342-25-00 JET,PILOT(#50)
Main: 4GY-14329-74-00 (#147)
 
Model: 4MR2, year: 1996, colour: Purplish white solid 1 (0206) Region: England
Carburettor: 4GY-14301-24-00
Nozzle: 4RR-14341-00-00
Washer main jet: 4GY-14153-00-00
Pilot: 43F-14342-25-00 JET,PILOT(#50)
Main: (147) 4GY-14239-74-00 (#147)

1997 Model: 4RR2; year: 1997; colour: Bluish black 2 (007B); region: Japan
Carburettor: 4GY-14301-24-00
Nozzle: 4GY-14341-20-00
Washer main jet: 4GY-14153-01-00 
Pilot: 43F-14342-25-00 (#50)
Main jet: 4GY-14329-74-00  (#147)
.........................................
Model: 4RR2; year: 1997; colour: テ゛イ-フ゜ ハ゛イオレツト メタリツク 1 (0297); region: Japan
Carburettor: 4GY-14301-24-00
Nozzle: 4GY-14341-20-00
Washer main jet: 4GY-14153-01-00
Pilot: 43F-14342-25-00 (#50)
Main jet: 4GY-14329-74-00  (#147)
 
Models: TTR250''L'', LC, R, RL and RLC Year:1999 Colour: Deep purplish blue solid e (0583); (plastic tank)
Carburettor: 5GF-14301-00-00
Nozzle: 4RR-14341-00-00
Washer main jet4GY-14153-00-00
Pilot: 43F-14342-25-00 (#50)
Main jet: All models with a ''C'' prefix (Californian) will be a #137, AU and the UK are #147. Unsure about the rest.
 
Model: 4PX5, year: 1999, Colour: Deep purplish blue solid e (0583); region: Australia
Carburettor: 4GY-14301-22-00
Nozzle: 4RR-14341-00-00
Washer main jet (part 8): 4GY-14153-00-00
Pilot: 43F-14342-25-00 (#50)
Main: 4GY-14329-74-00 (#147)
 
Model: 4PX8; year: 2002; colour: Deep purplish blue solid e (0583); region: France
Carburettor: 4GY-14301-24-00
Nozzle: 4GY-14341-20-00 
Washer main jet: 4GY-14153-01-00
Pilot: 43F-14342-25-00 JET,PILOT(#50)
Main: 4GY-14329-74-00 (#147)
 
Models: TTR250''M'', MC, N, NC, P, PC, R, RC, S, SC, T, TC, V, VC Years: 2000~2006 Colour: Deep purplish blue solid e (0583); (plastic tank)
Carburettor: 5GF-14301-01-00
Nozzle: 4GY-14341-20-00 
Washer main jet: 4GY-14153-01-00
Pilot: 43F-14342-25-00 (#50)
Main jet: All models with a ''C'' prefix (Californian) will be a #137, AU and the UK are #147. Unsure about the rest.

Enjoy!
Jarrah


-- Edited by TT-R250M on Saturday 11th of January 2014 12:20:07 AM

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That's an excellent work of reference Jarrah - very many thanks! 

Brian



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Thanks Brian, it took me ages to go through all that Japanese writing and translate it all but in the end I made it. wink

Jarrah



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You translated Japanese!
I got my friends Japanese wife to translate 'Feng Shui'. It means 'Tidy up'.

Looks like two nozzles, 4RR-14341-00-00 and 4GY-14341-20-00, two pilot jets, 48 and 50, and three main jets, 137,142 and 147.

I'm not sure I see a pattern between the implementation of the different nozzles and different jetting set ups though.

Oh hang on. There's a 4GY-14341-00-00 nozzle.


Oh well, maybe It's more than my tiny brain can follow through.

Andy

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Dullthud wrote:

You translated Japanese!
I got my friends Japanese wife to translate 'Feng Shui'. It means 'Tidy up'.

Looks like two nozzles, 4RR-14341-00-00 and 4GY-14341-20-00, two pilot jets, 48 and 50, and three main jets, 137,142 and 147.

I'm not sure I see a pattern between the implementation of the different nozzles and different jetting set ups though.

Oh hang on. There's a 4GY-14341-00-00 nozzle.


Oh well, maybe It's more than my tiny brain can follow through.

Andy


 I didn't literally translate the information, I got my two ex wife's to do it. Their names are ''Google Translate'' and ''Bing Translator'' (so glad we broke up, they were doing my head in lol). I think they may be related? biggrin

First of all, let's talk about part numbers-

The first 3 digits represents what model the part was first fitted to. This can effect fitment but will not always be the same digits i.e.- TTR's use 4GY, 4RR , 3XJ, 2VM, 4PX (only for 1999~2013 models), 4V4 etc.

The next five is the fitment info, if any number is different it will not interchange.

The next two digits represents whether the part has had any design change to it. These digits have no effect on whether it will interchange or not. The design change will not effect fitment.

The last two is the colour or finish and has nothing to do with fitment.

So as you can see, all the below parts listed in my post above are interchangeable.

..............................................................................................

There is no relation between nozzles or main jet washers/fuel baffles. You can use any one you choose to in any combination.

There is also no relationship between main nozzles and jet sizes. The only thing that relates to anything is the fact that different countries have different sizes. This is due to emission regulations.

Jarrah



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nice list. it might be worth also pointing out that for the main and pilot jet, the 2nd last digit pair are actually the jet size divided by 2 and rounded up to the nearest whole number if needed. (luckily they don't have a #200 jet or it wouldn't fit).

-24- is #48
-25- is #50
-69- is #137
-71- is #142
-74- is #147

Yamaha are not 100% consistent in subdivisions of the part number, eg fasteners also have a slightly different pattern.

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brindabella wrote:



 Yamaha are not 100% consistent in subdivisions of the part number, eg fasteners also have a slightly different pattern.


 Yes, I posted this over a year ago here- http://ttr250.activeboard.com/t50448087/usefull-internet-links-info-for-restorations-and-maintenence/

However, that has nothing to do with this thread.

Jarrah



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I lost track a little on the this thread. Just checking, are you running the 4RR nozzle on your blue TTR carb with no problems Jarrah?

Brian



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TTRfan wrote:

I lost track a little on the this thread. Just checking, are you running the 4RR nozzle on your blue TTR carb with no problems Jarrah?

Brian


I think you mean 4GY (V05) nozzle Brian as 4RR relates to the V95G0 nozzles. It could become confusing quickly if relating to the nozzles in this way as the models also use the prefix of 4RR.

I am using the older 4GY V05 in the newer 4PX carb  with no problems, if anything the shorter nozzle adds performance, as suggested here-

TT-R250M wrote:
brindabella wrote:



 by the way I think I misrepresented Jarrah in my post above - actually he had discovered that the older shorter nozzle gave better performance for him, and the float level did not have to be adjusted. I have a hazy idea that Lin may have also discovered the same difference in a post somewhere in the history of this forum (but I didn't check).


 Correct! I didn't want to correct you as it may have confused things.

 

 Jarrah



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V95-4RR nozzle 001.jpg

Perhaps we have a new fly in the ointment Jarrah cry

The pic above is of a new 4RR nozzle. Note it has a V95 reference rather than V95G0. It also appears to be the same length as the V05 i.e. short - see pic below with the V05 on the right confuse

Main jet emulsifiers or nozzles.jpg

Brian



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Very interesting Brian, what year model(s) was that for?

Do you think you could measure them to be sure there is no difference please?

Cheers,

Jarrah



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Never mind the year it was from, I found that out already-

Purchase this Yamaha 4RR-14341-00-00 NOZZLE MAIN --- NOZZLE, MAIN
This Yamaha 4RR-14341-00-00 NOZZLE MAIN is used on these models and components:
 
1999 TTR250L CARBURETOR
1999 TTR250LC CARBURETOR
1999 TTR250R - TT250RL CARBURETOR
1999 TTR250R - TT250RLC CARBURETOR

Very interesting, it means there is now four different types of nozzles, one of which nobody has even seen so far (the 4GY-14341-20-00 ). confuse

The plot thickens...



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The V95 (4RR-14341-00) is 50mm which is the same as the earlier V05 nozzle compared to the later nozzle's 52.90mm (V95G0part # 4GY-14341-20)

So it would seem that the V95 would work perfectly well in the later blue TTR carbs?

Brian

 



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TTRfan wrote:

The V95 (4RR-14341-00) is 50mm which is the same as the earlier V05 nozzle compared to the later nozzle's 52.90mm (V95G0part # 4GY-14341-20)

So it would seem that the V95 would work perfectly well in the later blue TTR carbs?

Brian

 


 I cannot see a problem with it given that I am using the V05 in the later blue carb- Models: TTR250''M'', MC, N, NC, P, PC, R, RC, S, SC, T, TC, V, VC Years: 2000~2006 Color: Deep purplish blue solid e (0583); (plastic tank)
Carburetor: 5GF-14301-01-00

Jarrah



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I just stripped an original carb from a 1995 Raid model 4GY5 and it has a V95 nozzle, 145 main jet and 50 pilot jet which supports the info in this thread biggrin

Brian



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