85 maxim fuel delivery problems

i have an 85 XJ700 with the hitachi carbs on it ... i have spent alot of time cleaning and re-synching the carbs and i think i am at an impass. i am not getting fuel delivery through the pilot jets on cyl 1 and 2 yet every time i pull them they are perfectly clean. none of the yahmaha dealers in my area stock any of the 365 jets all they have are the 41's has anybody ever installed and ran those successfully or have any ideas on my fuel delivery problem.

 

I should mention the bike runs only when being choked. and that all the bowls are filling with fuel.

 

Have you checked the enrichment jets in bottom of bowls and all of the air jets also? Could be a plugged air jet.

Chacal our parts guru carries all kinds of jets just PM him. However I have to ask if the jets are perfectly clean what would replacing them do?

 

yea i did a full lower chem soak on these for a few days and blew air through all the passages.... everything looks good. my only concern with the jets is that although i can see through them i may have distorted them during removal.

 

That makes sense, you can test that by swapping them and see if the problem moves with the jet. At least you will know if you need to keep looking.

 

a big thank you to mcrwt644 who had me pull the mix screws and clean. i re-installed them and set for 2.5 and the bike fired right up. it now runs like its being beaten with a 2X4 (or being chased by my wife they are about the same) and there is almost no such thing as granny speed. kinda shocked me when on my test run i decided to squeze the throttle a little only to have a runaway top end shifting at 9500 rpm(thats where is started losing power). Front tire pulled up at about 7100
and acted like it wanted to do it again in 2nd, and 3rd.

a few wheelies and a huge adrenaline rush later the idle jumped to 2600... but if you hit the kill switch off and right back on is settles way down to 1050rpm.... gonna re-clean them tonight with some carb cleaner.

What a Ride - made me feel like a kid at a carnival (i wanna do it again mom!)

 

i should also mention that if you happen to be equally as stupid as me when cleaning the mix screws and springs, if one of yours shoots out of your fingers across the garage into the eternal abyss corner where half your life is stored and cannot be found, take the spring from a mechanical pen fully compress the spring and measure it to the same distance as one of the others (on mine it was nearly the entire spring except the tension windings at one end) it works ... so now i am going to be trying to find a set of OE springs.

 

PM Chacal on this site - he has all the parts at good prices....

 

Removing and Cleaning the Jets is only HALF the Job.
You have to blow Carb Cleaner through the Pilot FUEL and AIR Passages.
Even if the Jets are NEW, if the Passages are clogged there won't be the necessary Fuel or Air movement for proper functioning.

Flushing the Pilot FUEL Passage requires removing the Pilot FUEL Jet and Pilot Mixture Screw with Spring, Flat Washer & O-ring.

Fill-up a Squeeze Syringe with Clean Carb Cleaner and Squeeze it through the Pilot FUEL Jet Opening.
Block the Pilot AIR Opening so the rushing Carb Cleaner exits the Pilot Mixture Passage.

Same for Main AIR Passage.
Flush the Main AIR Jet opening and lookk to see that Carb Clelaner is exiting through the AIR Passage in the Emulsion Jet Tube.

 

cool, thats sounds pretty effective. i'll do that tonight and see what happens. all i had on hand last night was my air compressor and a very little cleaner with no squirt tube on the can. i blasted everything thorougly with 100psi of air with a high pressure tip, squirted what little cleaner i had in each one let it sit for a few min and blasted it again.

any thoughts on if that mix setting of 2.5 turns is accurate i had been given a recomendation of 3 turns.... i am getting ready to drop in a new UNI Air filter tonight and i dont want to have the mix off.

 

2.5 to 3 turns is a starting point - you have to tune the bike from there. Look up plug chops etc. Also there really is no substitute to full breaking down and cleaning the carbs. Most of us learn that after several sort of cleanings.

here are Rick's excellent instructions

Clean carbs
http://www.xjbikes.com/Forums/viewtopic/t=2908.html

 

ok i got it all cleaned out.... i got the yamaha shop manual from the previous owner (this would have halped alot to have before) i wanted to post the fuel curcut picture for everyone, once i saw this it made alot more sense whay it had been having issues. in the picture you'll see i bent the tip of the spray tube on the carb cleaner. it was fairly easy once the mix screw / springs / gaskets were out of the way to clean the pilot mix fuel circut. just barely bending the tip you can insert it in the circut tube and spray. in the process i figured out that 2 metal washers were missing on number one & two so it's off to the auto parts store i go to get those before trying to tune it again.

i am willing to bet this will resolve the issue since cyl 2 & 3 took longer to produce the nice clean sound when spraying into the fuel circut.

 

hmm cant post a pict ... ok i'll add it to my gallery for those interested

 

Size your pics 500x500 pixels max - that will help.

Congrats on getting them clean. The manual is essential for sure.

 

here goes 500X500