Xj750 drilled out jets catastrophe

Just my .02, you got to clean them (carbs), sync them to run together, with your mods, it will be a journey to get them exactly right....the above members have told you what you NEED TO DO, there is no "This jet setup will work", its trial by error....

My case was, I went pods, 4 into 1, I was going to start with 118mains, 40 pilots, shop didnt have 118, so just for shits n giggles I ordered them but bought 122's they had, installed....BIG Difference!!! through out rmp range still a little bit of a hicup at lower end.

Plugs look good, choclate colored when I plug chop them, but want a little richer just my prefernce, so Im going to install 41pilots hoping it takes care of lowend, and shim my needles and see what I get from that...

To get running "good enough" is not getting it running the way "I want it"...trial and error, time, patience....or just buy you a new ride. Just take your time, do it right, its trial by error when it comes to modding, what works for others may not work for you....

 

Di it run perfectly before you changed the exhaust and went to pods?

If yes, then play with the jets. If it had other problems, you will chase you tail playing with jets alone.

As for drills, jet drills are small increments and not your normal drill set. It is possible to solder closed a too big jet and redrill it correctly, but I would advise doing some size research and check the drill bits with a micrometer.

Measure twice, drill once. Think three times about what you are measuring.

 

Ric,

Do the clock mean something like.... It's a new day, get up, clean yourself up, eat breakfast, grab a cup of coffee and left click the self "refresh" icon. Good, now go forward and have a good day?

Gary

 

I did not install the pipe just the pods. The guy i bought the bike from said that he had the bike jetted for the pipe but he obviously didn't. I am 100% sure i am not going to screw with anything that doesn't need it. Iam not going to tear apart my dd to do some stupid dealer suggested maintenance.

 

you got that right, you da man

 

Like adjusting the valves? Setting the float levels?

The DEALER doesn't "suggest" anything other than what the manufacturer did.

You ignore all the critical maintenance you want to; the bike will just die eventually.

 

The reason why so many forum members have acquired a Yamaha XJ-Bike for short money is because the Previous Owner ignored Perscribed Scheduled Maintenance, the bike wouldn't run, could no longer be ridden until repaired, and the parts and labor costs to rehab the bike to roadworthy condition became astronomical.

Those who could wrench took the sitting messes off the hands of those who neglected their bikes or failed when modifying them, and took care of doing what the others wouldn't do or regrettably undid.

What you should have done with your bike is to have used the Prescribed Maintenance Schedule as a check-list.
Returned the bike to a state of all its component parts functioning properly and within the specs of well maintained and finely tuned machine.

Once you had the bike returned to a condition where it was running quite well and had a base to return to, should mods present known difficulties, should you have begun your situation complicating experimentation.

Go back to START.
Do not pass GO.
Do not collect $200.

 

I'd like to add.....listen to the advice that's been given. Everyone who is telling you to do it the right way have all made the mistakes that you are making now. Chasing your own tail will just waste your time and make you even more frustrated than you currently are.

 

Come on guys, obviously this fellow knows what he is doing. He does not need extra advise nor the stupid stuff that the dealer suggests.

He clearly understands his bike and is on his way to build the world's fastest xj ever.

 

Worlds Fastest:
I didn't research what carb is put on your bike but if it is a Mikuni your available jet sizes increase 2.5 between available jets.
Your bike came from the factory slightly lean but not so lean that going up 2.5 will make it better, usually. If you can go up by 1 it may be better but I don't think you will find the jet.
Now if you add pods or different exhaust often one jet size will perform better. If you do both maybe two jet sizes.
As other have said, this is only if the other things are right.
So if you want a quick stab at it, buy the next two jets richer and do a "Trial & Error". Since you have to pull the carbs to do this I would recomend wet setting the floats. That will elininate one possible problem and is easy to do with the carbs off.

Good Luck

 

I am confused as to why you guys think that i have time to tear apart my motor and check valve clearances, fiddle with carb syncing, and float levels. I WORK and i use my xj to get me to work rain snow sleeet or hail my seca will prevail. I needed to re jet it, due to a super lean condition, due to the pods and after market 4-1 pipe. I rekon i am going to put 126 mains in and im still not sure if i should go 40 or 41 pilots. Thats where you people can help. Not by giving me a bunch of stupidly obvious advise on things that one would need to do if he wanted the worlds fastest xj.

 

This thread is a lost cause.

 

You know it it wouldn't be a damn lost cause if you old coots would just answer the stinking question. I asked numerous times. WHAT COMBO WOULD YOU PEOPLE USE. a 126 and 40 or a 41 THAT IS ALL. Nothing else don't give me any other info. All i want to know is what you personally would do. !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

 

Go with the bigger pilot jet.

We're not suggesting you "tear your motor apart." The things you need to do are MAINTENANCE ITEMS, simply that. Valve clearances, every 5000 miles. Ignore long enough, bad things happen.

We're trying to tell you that there is more to solving your issues than just re-jetting. And it WILL require you get the float levels right and re-sync the carbs, or it won't idle properly nor respond to throttle correctly until you do.

And until everything else is right, your re-jetting efforts will be very frustrating.

So ignore us. And fight with it for a really long time. Have fun with that.

 

Ok i appreciate the answer finally, that's all i was asking this whole time. And i understand that it is regular maintenance but what i still fail to see is why i would have to reset float levels when i did not remove the floats or needle ? And why synce them wheen they dont leak and i didnt seperate them?

 

If you take them far enough apart to change the jets, they'll need to be re-synced. Period.

Float levels need to be VERIFIED; if they're fine then don't fiddle with them. If they're NOT fine, you'll never get the bike in tune. Period.

You cannot do a good accurate running vacuum sync unless the valves are in spec. Period.

The work you are doing WILL require a re-sync. Period.

End of discussion. Fitz out.

 

Last year I started getting AARP letters in the mail. Now I am officially an old Coot. I guess altziemers is next...

 

okay so still getting a tude so i still dont know why i will have to tear the carbs arpart to replace two jets in the bottom of the carbs?

 

I totally understand were you are at. Yes, you can change a jet without breaking the rack. It would still be worth the time to check your float settings (wet) and do a bench sync before you re-install the rack. In the last 20 years I have had mine off about 4 times for basic cleaning and those settings were always off a bit. It just takes some of
the guess work out of the final tune if you know these are squared away.
And as always +1 to all the wisdom the Wizards said above its all important
good luck to you...

 

i told ya once dude
"here's what i got after a whole bunch of farting around, uni foam filter in stock box with mac4/1 pipe and super trapp muffler with 4 plates.
main 126, low jet 41. started with 8 plates then 6, settled on 4 in the super trapp"
what part of that don't you understand?