Jet needle source ???

[underdog57]

It looks like one jet needle is toast on my set of xj carbs ...
any where to get these ?? I would go used if good ...

the number is 5GLZ-34 . Has one clip position .
51.44mm long and the taper starts at what looks like 22mm.
Tried to match it to mikuni list but am not familiar with all the nomemclature ..

Bail me out here !!

Bob

[John]

Theonly place that I know will have them is motorcyclecarbs.com. He may be a little pricy, but he'll have it, and it will be OEM.

[underdog57]

Well if it brings the carbs back to life it will be worth it .
looks like one jet needle might do this bank of carbs ...

the 79 carbs I went and broke an idle mix tip . Cant get it out yet ...those were running pretty close before that happened ..

Thanks
Bob

[tommystinson]

PM me or just send me a SASE and I'll give you one of mine. BS34II parts are made from unobtanium nowadays. I'm daydreaming of the Keihin CR roundslide carbs for the Falcon. Only $700... no BS, no headaches, no trouble finding parts. Not quite as cool as the Megasquirt route, but plug-n-play is attractive...

[bakenath]

I am putting k&n filters on my 82 XJ11 with stock carbs and stock exhaust (I may switch to MAC 4-2 or Jardine 4-2 if it is compatible with my 82). I am located in Pocatello Idaho with elevation at 4365ft. I will be travelling this summer to several locations (boise 2700ft for 1 week, soda springs 5840 for three weeks). I have four questions:
1. Do I change pilots and/or mains?
2. What do I change them to?
3. Where can I buy them?
4. Any other precautions when doing this job.

You guys are all great! Thanks for your help.
Nathan Baker
801-649-3029

[underdog57]

Originally posted by bakenath
I am putting k&n filters on my 82 XJ11 with stock carbs and stock exhaust (I may switch to MAC 4-2 or Jardine 4-2 if it is compatible with my 82). I am located in Pocatello Idaho with elevation at 4365ft. I will be travelling this summer to several locations (boise 2700ft for 1 week, soda springs 5840 for three weeks). I have four questions:
1. Do I change pilots and/or mains?
2. What do I change them to?
3. Where can I buy them?
4. Any other precautions when doing this job.

You guys are all great! Thanks for your help.
Nathan Baker
801-649-3029

Nathan ,
These are CV carbs so elevation is compensated for . There is a tech tip on jetting rule of thumbs .
Go to the home page and scroll down to carb mods .
Good luck
Bob

[underdog57]

Originally posted by tommystinson
PM me or just send me a SASE and I'll give you one of mine. BS34II parts are made from unobtanium nowadays. I'm daydreaming of the Keihin CR roundslide carbs for the Falcon. Only $700... no BS, no headaches, no trouble finding parts. Not quite as cool as the Megasquirt route, but plug-n-play is attractive...

I'm getting interested in the Mikuni RS carbs ....
They do pop on , off just a tad on the center carb boots....
RS36 for the gsrx . Have to change the fuel petcock .....
Doesnt sound too bad...

Plug and play is a plus ...though
Thanks for offering the jet !! Pm'ed you...

Bob

[bakenath]

Okay this is what I have:
1 for stock exhaust
3 for individual filters
=4
-1 (standard deduction)
-1 (mismatch condition: individual filters and stock exhaust subtract an additional 1 jet size)
=2

Do I calculate a pilot jet size change before or after the deductions!!?? This will really make a difference: Either I go up one size or I stay the same!

Hitachi Carbs stock main = 112.5 + (2.5*2) = 117.5

Hitachi Carbs stock pilot = 47.5 + 2.5 = 50

And...
Question #3.
Where can I buy them?

Nathan

[mro]

originally posted by underdog
the 79 carbs I went and broke an idle mix tip . Cant get it out yet

Little goodie bottom right in pic.
Made from a tap (very hard steel).
Hold w/vise grip and place tip in pilot hole, give grip a tap with small wrench and broken needle tip should pop out.

pm me your addy and I'll send it to you if you think it will help.


mro

[underdog57]

Hi MRO ,
Will pm my address , will mail it back after...
I think this will help very much !
Thanks
Bob

[TopCatGr58]

Originally posted by bakenath
Okay this is what I have:
1 for stock exhaust
3 for individual filters
=4
-1 (standard deduction)
-1 (mismatch condition: individual filters and stock exhaust subtract an additional 1 jet size)
=2

Do I calculate a pilot jet size change before or after the deductions!!?? This will really make a difference: Either I go up one size or I stay the same!

Hitachi Carbs stock main = 112.5 + (2.5*2) = 117.5

Hitachi Carbs stock pilot = 47.5 + 2.5 = 50

And...
Question #3.
Where can I buy them?

Nathan

Hey there Nathan,

Here's an old megathread from Mike Hart regarding his replumbing and rejetting his XJ for Indy filters that IF YOU HAVE THE TIME, would find it possibly interesting. What I have gleaned from it is that you can go up many times the jetting guide recommendations for mains with good results, similar mileage, so don't need to worry about the specificity of getting it within 1 jet size!!!!

He went from stock 112.5's to 140's and was able to ride it without fouling his plugs. Possibly due to the YICS it may be less sensitive than the older bikes? So, going to 120's should work well, and you can get them from MikesXS.com large head style main jets, $6.00 a pair, need 2 pair. Regrettably Mike doesn't stock the 117.5 size, just 115 or 120 and up?
And many of us have not bothered with the larger Pilot jets, and have good results with just turning out the pilot screws an extra turn or so! YMMV
T.C.

PS, I remember seeing someone posting about a NEW COMPANY out of Canada making carb rebuild kits with jet needles and such, decent prices, just can't remember and don't have much time for search right now!
T.C.

[underdog57]

I bought my kits here http://www.carbkitscapital.com/
Not sure if they have much for the XJ , but if you pick an 80/81 carb kit that should be the same float valve and seat .
I'm going to try 78/79 jet needles on the xj . So you might have to mix and match ...

On the 78/79 carb kits , I used the kit eccept for the jet needle , it looked smal and differant . But everything else looked very good .
14.95 for the complete set ...I;d buy them again

Now I want to try to mod the 78/79 Idle mix screw orifice .
I broke another mix tip and would like to get beefier jets . I was carefull...homest .
wonder id drilling them and putting stronger jets in would be worth it ??

Bob

[mraaaaaaaaaa]

mixture needle

Hi Nathan,

Found 3 of My mixture screws broken off.

What I did was ground out the tip from the inside of


of the carb..

Got a small handheld grinder from Harbor freight tools.

Cost like $ 4.00 and has all kind of wheels, brushes, etc.

I took My 1 good 1 and set it for 1 2/2 turns out.

then counted the turns out . Put the busted ones back

and when they were bottemed out, there was only a1/4

turn difference from the good screw, started right up

and runs/idles gr8 !! weird huh ??

then I synced with My new guages from jc whitney, and,

suprisenly, I synced with 1 guage a few days earlier

and it was darn close.

I do not think the ground out area in the carb had any

kinda effect at all . In fact, I think It allows the mixture

to swirl around a little, which, I think helps in the

mixture atomising.

Mayb this will help, mine finally purrs/screams..............

TC< & keep da back rubber down, ltr !!