jets on the mikuni's

I have a 1985 xj700, in Edmonton Alberta, Canada. bought it in 1993 only one year outa the crate, and only 3500kms on it!

I also have a venture Royal that i use most often so the "little" xj now only has 26000k...

I have consistently had issues, like others on the site, with the fuel shut offs. i am looking to install a briggs shut off in line with an additional filter of some kind. Can some one give me a model number that they have used with sum success? Many thanks in advance.

Also... with the low kms and plenty of "winter" storage time over the years, the tank has extensive corrosion resulting in very poor performance last summer / fall. So.... i am now re and reing the carbs!

I have taken them off, dismantled all parts except for separating the four units. in so doing, i have stripped one of the jets... dang... 20 of em and i only got one that was siezed!! it is the smallest jet on the float bowl side, reads 40. I am looking to find a source for replacement.... advice on how much further i need to go on the tear down?

Any assistance / advice is welcome!!

ps - looking for more xj'rs in the frozen north!!

 

Hello, The jet is called the-- pilot fuel jet. Right beside the Main Jet.
The one under the diaphram is the pilot Air jet.
I de-winged mine, so I took a very small screwdriver I got from Radioshack--The fine electronics screwdriver set.
Hammered it in GENTLY and it grabed enough to turn out.
You can ask Chacal if he has any in stock.
http://www.xjbikes.com/Forums/viewtopic ... html#65977

The big problem seems to be with the "Pilot Screws" If the carbs are
up-right, there the closest to the motor. Right in front of the diaphram cover. Some virgin carbs have "caps" on them so you can't see them.
When I took mine out the #4 carb Pilot Screw aka "Mixture Screw" was full of dust and powder. I used "Carb and Auto Parts Dip", to just dunk the whole carb in.
Made by Kleen-flo. It's a tad on the corrosive side so it will completely eat
ANY O-Rings or rubber like the diaphrams, fuel tube o-rings, throttle shaft
seals.
The jug says it will cause Heart Arithmia, so I know it'll clean em-good!

As far as how much to tear down, you can check out the Thread:
CLEAN YOUR OWN CARBS AND QUIT BITCHING ABOUT THEM!
It's indepth and chock full of info.
Hope you have better luck with the rest.

 

Hehehe... Yes, hammer it in. Gently.

I love it!

 

hey guys, tks for all the information, it really helped out. i have the carbs back together, clean as a whistle!! I will do a complete tear down, separating the four units next winter!

my next question - what do u recommend using to clean / condition the tank? it is full of small pits and had a lot of brown crap in the bottom when i removed the petcock - again!! it still leaks as per previous threads, so i will be installing a shut off and filter in line before the carbs. so i will not have to modify the petcock. note - this is a brand new unit installed last spring, only one season on it and it leaks.... not surprising now that i have the tank apart again!!

What do i clean that crap out with? And what do i condition the tank with before filling it up?

Many thanks in advance - cant wait to get back on the road!! its spring finally in Edmonton!!

 

The brown crap sounds like surface rust, another problem with old bikes.
I've used "Cream"on one tank but it didn't work out for me. Directions said to use a small current of air through the fuel cap hole to aid in drying time, it wrinkled the coating inside and I wasn't impressed. 8O
I've purchased "Por 15", but haven't had the proper weather to try it out.
First I'm going to try the "electro-chemical" method. It's salt water and a battery charger that can put out 10 amps. I saw it on the XJ FAQ Page.
About 2/3's of the way down the page
http://www.i-op.com/jimm/xjfaq.txt
It's cheap enough to give it a try.

Sounds like the "crap" in the tank might have blocked the diaphram open in the petcock, try taking it apart to see if you can clear it out.
Remove the petcock, block the hole with a piece of body metal cut to size and bolted into place, put clean gas in and swish it all about. Take off the little plate you made and drain. See how bad the rust is.
Throw in 10 small bolts that will fall out the petcock hole if you want to, Just make sure you have a flexable mechanics magnet handy if they don't want to come out. It's a light scrubbing affect. 8)

 

hey guys, im back!! Had some interesting events these last few months with the xj! I flushed the tank several times, followed the link to rebuild the petcock and installed an inline fuel filter and shut off! Now even with the factory petcock i get good shut off! Thanks for the link!

Installed the carbs after bench syncing them - must blew it i think cause i cant get the idle to come down or it varies from one warm up to the next, some times it will come down onto the idle screw adjustment when cold but as soon as it warms up during a ride, it is running around 25 to 3 k and adjustments to the screw do nothing! Cold its ok, warm it up and ZOOM!

Help!

 

Did you do a "Clunk Test"?

Did you polish the Diaphragm Piston Bores?

 

Hey RickCo... thanks for the quick reply! Not sure what you mean by "clunk test", and no i did not polish the bores. I am up late taking them off the bike again tonight!

Reading through some previous posts I am confused with the bench sync process. Thought i had it down as i used to work on 70's muscle cars with the old 440 six packs etc. But this one has me! Can u point me to a link for the proper proceedure, or assit me with the bench set up?

I also see the YICS posts and would like to have a firm idea on how to sync them up when back on the bike!

Confused / and a bit frustrated cause it was not doing this before i took em off, just running a little rough!

 

my bike does the same thing, removed the tank and the top caps off the carbs, clunk test seems to be ok. im confused as hell

 

To follow up, iv bin ridin her tonight for a few hours, and she is running a bit rough but i got her idle back under control every time. Noticed she takes a while to come back down though, so on the comp and researching the site again. Man this ROCKS! You guys are right on the money with this site!

oh k then, more research and this time i will get it right i am sure, just read through the post on clunk test, WOW RickCoMatic..... WOW that is one hell of a post, exactly what we needed!
Next step after the "polish" is the bench sync, then on to reinstall!
Final step will be to get the YICS tool and do a running sync of those babes!

Many many thanks again RickCoMatic!