Help! 1992 TZR250 3XV Japanese domestic Carburetor basics, staggered Jets.

[TZR250SMOKER]

Hi Folks, sorry about rookie q's, I have read and read and can't 100% confirm this stuff.  Any help much appreciated! Thank you.

Bike: 1992 TZR250 3XV imported from Japan directly to me here in Florida. Engine stamped 3XV, one cylinder stamped Y-1, the other Y-2.  Both stamped 3XV01.  I measured the carbs and they measure 28mm.  Frame #3XV-048308

1) Can I conclude that the upper cylinder stamped y-2 is the #2 and so on?
2) Is it correct to say that the Larger main jet goes in the upper #2 cylinder?  I accidently lost track when I removed them...
3) My main jets are stamped 220 and 175.  Everywhere I look I have not found that size, data on this site says they should be 190 and 260.  Is this because I have a Japanese domestic bike?  Did someone put the wrong ones in? Should I keep these or get 190 and 260?
4) My pilots are both #15
5) My needle jets are stamped 673 on each and then one says P-8, the other Q-0.  I lost track of these too, are they identical or different?  They look identical.. the chart on this site says #1 P-8, #2 Q-0, does this means that the #1 (lower cylinder) takes the P-8??
6) I am 99% positive that I know where my float bowls go but I can't be sure that someone didn't reverse them before me. I have never run this bike.  I think the lower cylinder (#1) takes the float bowl that has and extra nipple and the one nipple is angled. This is also the carb that has the extra thing on top with the electrical connection, what is that called?
Pics attached.

Thank you for any help.  Kurt

[mellorp]

Try the link at the top right for manuals etc.

[TZR250SMOKER]

Thank you, I will take a look.

[TZR250SMOKER]

I was in there on that chart and it does not make sense for my bike. It says main jets are 260 and 190 and I still don't know which one goes where.  Does the stamp on the cylinder Y-1 mean that is cylinder 1? I figure it does but that contradicts some info I have read.  Do I put the jets labeled #1 on the #1 cylinder? Makes sense I guess. My main jets are printed 220 and 175??

[ybk]

1. Heads and cylinders are interchangeable. The heads are stamped Y1 and Y2 - they are identical except for the water spigot sealing method, as far as I remember the Y1 is sealed with a gasket and the Y2 is with an O ring.
2. Main jets differ across the the models, no real pattern as such. Carb settings here: http://pure2strokespirit.net/forums/index.php?topic=329.0
3. Your frame number suggests a 3XV4 but your carb internalsis closer to 3XV1. With a 3xv4 you're looking at a 200 jet on the rear/top cylinder and a 270 on the lower/front cylinder. Your previous Japanese owner probably rejetted the carb? Probably a good idea to go back to stock jets and see how it runs?
4. Stock pilots for a 3XV4 is 12.5 in both (15 for 3XV1). See how it runs before making changes or start with stock carb jetting and move from there..
5. Your needle jets match that from a 3XV1 so probably easier to move to stock 3xv1 main jets if you want a 'stock base'.
6. Yeah, lower carb float bowl has 2 outlets and the carb body has two baffle plates on the roof of the float chamber. The Eiffel tower on top of the carb is the throttle position sensor. It also has the idling adjuster on it(the knurled adjuster, not the screw one). The idling on the top carb is on the carb body itself.

Have you got more pics of the bike itself?

[TZR250SMOKER]

Thanks a million!  I was starting to get a clue after crazy amount of hours researching this.  I figured it might be a 91 motor in a 92 frame so I just pulled the rear cowl and checked the Computer and it is a 1992.  So my last question to you that might confirm if this is a set of 1991 carbs on a 1992 motor is the Power jets, I see the 1991 says 50,60 and the 1992 says 40 and nothing.. where are these power jets, I figure they are some tube with a hose leading fuel back into the air stream but I cant figure out where.  Can you tell from my pic if this has the 2 power jets or just the one? 

My plan since I see the computer is a 1992 was to re jet it back to 1992 and do the 200, 270, 12.5 pilots and the P4,P6 needle jets.  Does this sound ok?  Thank you very much.

[TZR250SMOKER]

I forgot to ask about needles.  Reading the chart is a bit confusing. Am I to use 5FN117 on both carbs with step 2? Thank you

[41juergen]

Karel, I think the marking Y-1 and Y-2 correlates with the left (#1) and right (#2) cylinder. The difference off the water spigot sealing at the head was the -00 version against the -01 version stamped on the haeds...., right?
So all data you can see in the manual refers to the left (Y-1) cylinder, head and carb and corresponding to the right (Y-2) cylinder. You can mix or exchange the cylinders and heads, but better don't do with the carbs.

[TZR250SMOKER]

Ooops, this contradicts my latest conclusion.  I was going with my head stamps.  The pic I posted of my head is the lower, front head, stamped Y-1. I figured this was cylinder #1 and therefore anything on the chart or parts list labeled #1 would go on the front, lower, right, bottom... carb.  I figure the #1 cylinder and carb is the one that crosses the finish line first. correct?  The needle I just pulled from the front lower carb corresponds with my theory based on chart info but these carbs seem to be fiddled with alot so who can be 100% sure.  I see what you mean that the heads seem interchangeable so they really don't mean much so am I wrong thinking that the first cylinder and carb to cross the finish line is #1 when referring to all parts lists?  Thank you, Kurt

[ybk]

Juergen, you are right, brain fade

Ooops, this contradicts my latest conclusion.  I was going with my head stamps.  The pic I posted of my head is the lower, front head, stamped Y-1. I figured this was cylinder #1 and therefore anything on the chart or parts list labeled #1 would go on the front, lower, right, bottom... carb.  I figure the #1 cylinder and carb is the one that crosses the finish line first. correct?  The needle I just pulled from the front lower carb corresponds with my theory based on chart info but these carbs seem to be fiddled with alot so who can be 100% sure.  I see what you mean that the heads seem interchangeable so they really don't mean much so am I wrong thinking that the first cylinder and carb to cross the finish line is #1 when referring to all parts lists?  Thank you, Kurt

Just match to top and lower carb (or front back, left right). Since you have pretty much the 3xv1 carb bar the main jets it would be easier to just standardize on the 3xv1 carb setup. The differences between the 3xv1 and 4 are quite subtle so I cant imagine it being an issue. That and I reckon it may tricky sourcing the correct 3xv4 carb internals due to most being NLA.

The power jets are in the float bowl and too be honest I'm not sure how to go about checking the identifying marks. I think they are pressed in? The carbs' true identity will probably be a mystery? The 3XV4 jet needle is 5FN117 for both carbs. Clip in 2/5 position counting from the top. 3XV1 is 5FN117 for top/rear cylinder and 5FN118 for front/lower.

You can verify for yourself as well, all the manuals have these specs, albeit in Japanese though. You can use the google translate app to help with translating:
3XV4:


3XV1 (SP in brackets):

[TZR250SMOKER]

Thank you again, I have installed all new jets and needles, etc.  I got a very nice kit from Webike, the Keyster kit for the 3XV4.  Now I am trying to check my vacuum hoses, etc.  It seems someone put a gravity fed petcock on her so I don't have that vacuum hose involved.  I took lots of pics before I took things apart but some of the hoses were broken or cut off and so there is some mystery. 

1) There is a white plastic fitting coming out of the crank case (see pic) with a clear (now yellowed) tube on it and it was just sitting there not connected?  Was that to the side of the LEFT carb where you see i connected it in the other pic?   
2) On the LEFT carb there is a nipple (pic with screwdriver blade pointing to it) is that nipple intended to be capped like on the RIGHT carb (are these just tuning nipples) or did it use to go to the vacuum nipple on the original petcock?  My petcock is not stock, it is a simple gravity one now.  Someone just capped the LEFT carb nipple with 6 inches of hose and a screw. 
3) In pic with finger on black hose, is that just an overflow hose that should be routed with the other overflow hoses?
4) In pic with short clear tube, I figure these are the "Power Jets" they suck extra fuel from the bowls under heavy load, vacuum load?

Thank you, much appreciated. Kurt

[Steveog]

So my last question to you...

Hi, Smoker. Please know I'm joking by saying, "There is no last question" with these bikes. There are many veteran experts here who don't agree and they even show up occasionally asking questions of the group. Its all part of our passion for these unique vehicles that must not be allowed to go extinct.

This is my second year anniversary here and my 3xv is finally running very well, but only because of the knowledge/database here and those experts willing to share it with us newbies. Don't let my "Hero" title fool you. HA. I just post a lot, asking questions just as you have.

Please don't think you're annoying any one with questions and inconsistencies. Good luck on your project. Between ybk and jueregen your getting Top Gun advice. Keep at it. The final reward is worth the effort.

Steve 

[TZR250SMOKER]

Your right, meant to say "last question for this post".. appreciate the feedback.  Glad your bike is running well, I should be kicking mine over today for its first fire.. so, by chance do you know any of the answers to my q's?  Does your bike have any similar features that might give me hints?  I'm 95% sure I have it hooked correctly but would like to be 100%. Thank you. 

[Warwick]

1. That's the crank case breather. It shouldn't connect to anything. Just route it to hang down behind the engine.

the yellow hose on the carb is also just a breather and shouldn't be connected to anything either. See the little routing loop casting for it on the carb bowl? Just tuck it in there and let it dangle free.

2. The stub the screwdriver is pointing to is the vacuum take off for the fuel tap. if not using a vacuum tap it is crucial that this is capped off.

3. Yes, those are the powerjets. It would be a good idea to put some clips on the hoses either end to ensure a good fit.

The most important thing there is to seal off that vacuum stub on the carb. But tidying up the other issues would be good too.   

[TZR250SMOKER]

Yes Sir!! Thank you, I did have it wrong... Would have been interesting when I fired it up..  Will do with the connections and clips, etc. I don't think I have good hose on there yet either, need some proper moto hose.  I'm considering going back to an original style vacuum petcock as I do like the way they work when they are working.  I am ready to fire!  Fire in the Hole!!! I'll let you know how she runs. Thanks again.