82' XJ750 SECA Idle issues jumping idle

i got this bike for free and it had some weird idle issues. When i brought the bike back home i started it up again and the idle goes up and down, mainly stays at a VERY high idle(idle gauge doesn't work). So i bought a carb rebuild kit and rebuilt the carbs and cleaned them up really good, checked the spark plugs, and it still runs the same at a weird idle. Im at a loss for whats the problem, im going to take it apart and replace the diaphragms, when i had it all apart one of the plungers had some resistance but it went normal after i took a break for a day? I do not get what the problem is could be simple could be huge. This bikes electrical system is all run on one fuse aswell but the idle is not electrical obviously but yeah whoever owned this bike kitbashed it together with electrical stuff. If anyone knows the issuse with the idle please help.

 

The idle is electrical in that you have the ignition system providing a spark on each compression stroke. Setting the idle is mechanical via the big screw between the 2nd and 3rd carburettors. What rating is the fuse? You need that sorted first with a blade type fuse box with the correctly rated fuse for each of the circuits connected to it. Chances are your diaphrams are fine, you want to diagnose problems and then buy the parts you need.

 

yeah the idle screw works good, it just jumps in idle randomly and stays super high idle, dunno what you mean by "what rating is the fuse" but the fuse block is shot, it wont turn over anymore because EVERYTHING is going through one fuse, i dont know how but someone managed to do it, diaphrams are good i repaired one hole in it with RTV. ive already diagnosed some problems but me and my dad are at a loss for whats the main issue why the idle is the way it is. it runs lean aswell like real lean

 

Original fusebox on our bikes pictured. Fuse rating refers to what amperage is the fuse. There should be four.

You could have a vacuum leak causing the high idle.



The fuse wiring needs fixed before you do anything else because you can damage your electrical components and you don't want to damage the TCI ignition box. Get a Haynes manual for your bike if you don't have one. Fit a blade type fusebox.

Similar to this.

https://www.eurocarparts.com/p/pear...lS_OEncwXIJLegnuYufHSo0l2AJTUgooaAoaDEALw_wcB

 

yeah i should be getting a book here in a week, for a vacuum leak i already replaced the boots, and now ive disconnected the wire going to the gas tank to the boot, it also has aftermarket airfilters on it without the airbox, so its probably getting more air from those and the petcock might be bad from the positive air flow to the boot. Carbs should be just fine so ive limited it to lean issues, jets, higher grade fuel and maybe go back to stock airbox if i can find one. Ive bought a fuse box off walmart but its not getting here for a month and i dont know how it install that blade fuse box, if its not to hard i could do that.

 

That is the vacuum line to operate the vacuum petcock not a wire. Pods will cause problems better with original air filter setup someone one here will have one I think. Some people have fitted them. I have not tried it due to the fact they are CV carburettors pods allow greater airflow so as you state that will make it leaner.

Fuse box info.

https://www.xjbikes.com/forums/threads/how-to-install-an-aftermarket-fuse-box.6350/

 

CV type carbs don't play well with pod style filters.

 

i would get stock but there is nothing on ebay or anything else, unless i want to pay over 150 bucks for a beaten one.

 

I see one on eBay for $50

 

https://www.ebay.com/itm/2656576780...GvOYHjQTja&var=&widget_ver=artemis&media=COPY

 

i found the problem, the pilot and main air jets were swapped around in all of the carbs, but now its got a stuck revving issue, when i give it gas it kinda sticks for a few seconds then goes back down, plus its running fat due to higher jets so im going to lower that. Any recommendations for why its sticking a bit?

 

just installed a new fusebox and it works good, just need to fix the idle stick, i posted more below if you know what it could be.

 

Can you post a video of the engine running? You can post it on YouTube and post the link here is you cannot upload the video directly.

 

yeah i can do that, its running a bit fat plus it needs a slight tune but ill record that in a bit

 

If all your cylinders are firing then it has to be carbs and most likely caused by the pods leaning the mixture.

 

https://youtube.com/shorts/PT3sAzPEWmE?feature=share, i thought it would be running fat due to it smoking more and an odd smell

 

you can also see the k&n filters, i bought new airbox and filter for it so that will be comming in hopefully in a week or two

 

yoink, thanks lol should do better than the K&N filters

 

You might be better leaving it because it doesn't sound bad until you get the standard air box fitted to see how it runs.

 

its not best to ride it, i had it running the other day and it got stuck at high revs and took it about 2-3 seconds to goto normal lowish revs. any idea? just thar its getting alot of air? i could clean the throttle cable while im cleaning the clutch and brakes

 

Lubricate the throttle cable and the twist grip and make sure the throttle is closing quickly when you release it. I think it's most likely too much air weakening the mixture.

 

hey i really appreciate the help, daily responses were a lovely thing. I got the bike to run normal at least idle normal. ill be testing it out here in a few days, im a new motorcyclist and i gotta learn on this beast so that will be a blast. if i find any issues i cant resolve ill be back on this forum. Plus the fix was putting in stock jets, the higher jets were too much i guess even for my altitude and i also had to loosen the plastic screws in the pison with the needle jet, i think they were keeping it open causing it to idle rough. Just needed to clean it out real good and not screw anything up! First carb build was fun and easy hope people my age will do this stuff. Anyways thanks again

 

Yep for me part of the fun is fixing my own bike. Learn all you can it makes motorcycling more fun when you understand how they work and can fix them. I am still learning .