ok total maxim noob

first off thnx for allowing me in here, i recently purchased a 85 xj700n, its has 88,303 on it lol ya i know.. but shes in really good shape,, ive been on the forums here for about a month and finally decided to join cause i think you guys know..ok,, well heres my problem.. it was boggin out and hesitatin so badly she almost threw me off, sparkys are fouled black,, so im thinkin rich..i leaned out fuel air.. and ran a hotter plug (im not rich) good for a bit,,(25kmh) and started boggin out..dyin again..so from what ive read on here i decided to take carbs off.. well they really werent too bad. shocking actually, abnd disapointing, so cleaned them checked jets.,. put it back together,, shes runnin great now.. but now she climbs on the idle up to 3000, no boggin no more, but idle is crazy.. i checked choke cable and wd40..and checked throttle cable..wd40.. she has twice the power she had but now idles too high,, everythings stock,, and the only thing ive done to her is what ive said? help?

 

Have you adjusted the idle screw to lower the idle?

 

First, if your cables are good, remove them and get the wd-40 out of them. Use regular motor oil to seep through the cable if that is all you have to work with. Wd-40 will turn to a gum and become very sticky after a while.
My bike behaved the same way. The truth is there is no quick fix. You have to do the entire church of clean to the carbs and have rebuild kits ready when reassembly comes around, then bench sync and then wet setting the floats. once that is done, then it is on to valve clearances and valve shim exchange to get valves in spec. Now it is time for a running vacuum sync with a yics blocking tool. If you have the bucks, colortuning the spark plugs would be good also. When I did all this...my bike fires right up with just a touch of a button and idles like a big purring kitty. By the time I put the helmet on, get on the bike, idle up to the street, turn right, shut off the choke and she runs like a cheetah chasing a antelope...Believe me, I would be all in for short cuts, but they only make you do the same thing over and over...hope this helps...

 

Welcome. You will probably save a lot of time by checking/adjusting your valve clearances before messing around with tuning/mixture adjustments.

Put your bike model in your signature and look for some of the first step posts here. Get the safety stuff done first (look for the rear brake delamination warning, there must be thousands of posts here about it...)

 

WD-40 is good for cleaning things and that is all. Cables will last longer and be more reliable if they are cleaned and lubed properly with a silicone based lube as they don't draw dirt.

Check your idle knob to make sure it's backed off as much as possible to correct your idle, but you might also have an air leak. Removing the carbs and replacing them can often lead to a leak due to the old brittle rubber on the intakes. Also make sure your throttle is operating properly with free travel and return. The advice about the valves is correct, they must be in spec before ANYthing else or you're fighting a losing battle. Don't fear this procedure as even on the hardest XJ they are not impossible, and on the majority of XJ's this procedure is quite easy. With the Km you have on that bike they are likely in need of attention. Don't forget about your brakes, make sure your cables and shoes are NEW!! VERY IMPORTANT.

BTW...Welcome to XJ bikes!

 

This IS pretty much your answer; and the WD40 thing is VERY IMPORTANT you can cause a sticky cable by using it.

You don't have to use motor oil, any good-quality automotive or industrial grade spray lube will work, I prefer Tri-Flow.

 

ok well thnx for the advice guys,, im slightly disapointed that there wasnt some magical thing thaT i overlooked lol and ya i have the idle screw backed all the way out, i am on the right track though cause she is runnin better, just fast idleing, and i will definately fix the cables im not sure if im going to play with valves i'll hafta really read up on it, one thing it is doing is backfiring when i shut it off from leftside just once,,any ideas what that could be? is it just from the fast idle?

 

For all cables and pivot points I use Dupont multi-use teflon spray. Goes is thin,lasts a while, does not attract dirt,and is self cleaning. Amazing stuff. I use it on my sportbike chains.

Before you know it, you'll be like me walking around your house spraying all your door hinges and stuff.

 

lol jayo ok thnx brutha

 

could be stuck float, could be valve out of spec, could be a combination of both, could be wrong jets, ...really...and I know this sucks...you really just have to take her down and go through it all. And the valve shims are easy peasy to do. If you never have worked on a engine, it is really basic and there are so many here to help with questions. The bad side, until you go through the 30 year old correctly, she will continue to act up and not run right.
Many have tried doing a little and not doing that or this and they get frustrated at the results and either start over and do it all, or the walk away from the bike, but rarely anything in the middle. Trust me, I had the carbs off twice and remounted before I took them off the last time and did the church of clean...I know sometimes it isn't the answer you want, but it is the truth....

 

well i watched a good vid on bench setting,,that i definately didnt do..i took one of the top covers off and inspected slider and main jet,, but that boot kinda didnt wanna go back on its seat right so it made me nervous to take rest off, i did get it back properly, so basically in a nut shell shes gone from boggin out dyin slowly to idling too fast but tons of power now, lol, and those intake boots are a massive pain to get back on, not much room there is there a trick to takin off carbs the painless way? i noticed gaskets on engine side so didnt touch them.. i put carbs on engine boots then slid the intake from airbox boots on and what a nightmare,, the inside ones were the worst, boots are like new not a crack or anything the guy that her before wasnt lyin he said its nvr even seen rain and i totally beleive him now,if i could just tune this bike in a bit better without havn to rip the engine apart it would be cool, as i honestly dont have a garage or a real work bench,,im tryin my best here, it just kinda a stumper, i know i need to listen to you guys when your talkin valves, i have pretty much exhausted all other possibilities now, the last owner did tell me the valves were just done last season and he nvr rode it this year,if i could get the idle down shed be a great ride ..finally.

 

I never trust a Previous Owner; it's not their life on the line anymore.

Reality check here, I'm not being a jerk.

You can't buy a 30 year old bike and just turn the key and go. If you just want to ride, sell it and get a newer bike. These older bikes need major upgrades and replacements to be safe and fun. The good news is that the work is doable yourself, and if the bike got to 88k km then it shows it's got a good core.

Check out this post from Al, he lists most everything. Sequence is very important: if you sync your carbs BEFORE checking valve clearances and you have to replace a shim, you'll have to redo all your carbs.
http://xjbikes.com/Forums/viewtopic/t=43470.html

We're here for you. Hell, I bet Fitz alone has pulled 100 bikes from a dead engine to back flying down the road with just words alone. You got this, dude! ^_^

 

ya im begining to realize she needs tlc, but ya i love the fact that everything is (doable) and no disrespect taken thnx for the help its not easy on yer own..and well we all know what phoning a motorbike shop gets you. i love this site. unfortunately for me i have a rain delay here and shes happy under her cover,

 

well one good word of encouragement to all you maxim pilots..yes as a matter of fact they do go to 88,000 kmh and still suprisingly enough still have power for days. and still gleam chrome in the sun, im impressed with these bikes.

bikes ive owned, cb 650
82 yammy rd 350
92 yammy fj1200 (gawd i miss her)
and now this one 85 xj700n

 

I loosened the clamps on the carb boots and pushed them into the airbox, I have also snatched them completely out leaving traces of human skin all over. Just no simple way I guess. Since it is raining there, you should spend some time reading the entire church of clean http://xjbikes.com/Forums/viewtopic/t=1 ... clean.html

Possible other reasons for a high idle is a vacuum leak. I would not mess with trying to remove or tighten the intake boots attached to the motor. The bolts just twist off with the slightest pressure. However, inspect them for cracks and if there are any, there is a rtv silicone method of patching them up. Check the vacuum sync port covers and make sure they are pliable and snug.

I haven't ever done this, but some guys start the bike and open the valve on a propane torch and move it around the intakes. If the rpm goes up...yup..it's a vacuum leak.

Every person who has done the valve shim clearance check has to pull the shim to record the shim number. I would think that everybody has a list of what current shims are in their engine right now. Would be a great question for the previous owner. That stutter that you will be hearing out of him next really means no maintenance has been done.

If all goes well, you can clean and rebuild your carbs on one long day. Most of the time when working on a 30 year old bike though...the ugly face of age and neglect will rise up to argue with you from time to time..

 

i can tell when im diggin around in the areas that you dont normally dig around in that cpt torque has been there, most of these screws are almost stripped, my rd 350 i switched them to allen bolts with locktight..so much eaiser