Question for where to go next..

I've been reading a lot so I think I've started down the right path but I'm not really sure what the general order of things to do is.

I have a 1982 XJ550 Maxim. I bought the Haynes manual and have the original manual that came with the bike. I have cleaned the carbs multiple times and I feel after 5 attempts they are clean. The bike would start and idle at full choke but would call on its face without choke. I went ahead and did the valve clearances and to my surprise 5 were out of spec, and oddly enough they were all out of spec tight. Once I changed the shims the bike would again start and not run without full choke. I am now in the process of wet setting the carbs, 2/4 were too high of a bowl level so I am adjusting the floats for those two now.

Once I get my bowl settings correct, where do I go from there?

Thanks for the help guys!

 

The valves get tighter over time on our bikes. It happens. I was 6 out of 8 over the winter myself. Running pods, or stock airbox?

Bench sync
Run it, get it to operating temp
Running vacuum sync, yics blocked
Colortune

But it's not just the engine to worry about. How are the brakes? Electrical? Chain? Cables and joints lubed? Bearings inspected? Tires okay?

 

It has fine tires, new sprockets, chain, front brake is rubbing a little.. Spark is good, I replaced the box under the seat, and did resistance checks on spark plug wires. I had the bike running on full choke prior to putting valve clearances back into spec, now it is a lot worse off. Went ahead and put my idle mixture screws to 2.5 turns out. Does bench sync just involve ensuring the butterflys are all about the same level? (in relation to #3 if i read correctly). Lastly, how do I block YICS?

And sorry, stock air box

 

Actually you mentioned bearings.. Could be the front bearing also didn't think about that. However, one step at a time, right? I put new choke and throttle cables on it last year (it's AMAZING to be able to get parts, thanks to Len at XJ 4 ever)

 

Yup, you got it right, just that all the buttertlies are equal. My bike was doing funny things after the rebuild too. Ended up being that the intake boot bolts were a little loose. On something so precise, every single bolt, weld, and component is suspect until proven otherwise.

You block YICS with a special tool. Syncing and colortuning can't be done (properly) without it. I can vouch for the tool. Some members gave some alternatives, but the bike didn't really come to life until I used the tool.

My bike seems to like running full choke for about 20sec, then half choke for about 5 mins or 5 brisk blocks until it will idle without it.

Usually mixture problems involve either the float levels and jets. Are the enrichment plungers closing all the way? Have you checked/cleaned them and their passages? I was working on a buddy's XJ, and the cable was improperly adjusted so that the plungers would always open full, but would stay open just a hair, running rich.

Yup, Len is the man. Even all the way up in Canada. He sells the yics tool as well.

 

I may have to pick one up off him. It just seems pricey. I replaced the needles last rebuild and they have been cleaned pretty thoroughly. Two bowls were getting maybe 1 mm more fuel than the others so I'm fixing the float heights for them.

 

Can you see thru the pilot jets in the carbs? I had to take bristles off my grill brush to poke they the pilot jets a bread tie was still too big. If they are plugged you aren't going to idle well at all.

 

Threaten to throw her off a cliff worked for me. After I did that came to life how ever that said go back to the pilot jets, then when you do get it running choke no choke, spray all the carb bodys with carb cleaner, exterior ideally, pay close attention to the throttle shaft seals if there is any change with the spray well you have other issues. Like throttle shaft seals, u cleaned the carbs ? Did you break the rack? Also set butterflys equal, back thumb throttle adjust screw all way out, set flys equal like the width of a credit card, pay close attention that all 4 open equal if not wont run right no matter what you do valves-synch cant do jack! A to rich or lean situation wont disrupt performance of the get go. Takes time to deteriorate performance. Now this said feel temps on all of the 4 into 1 exhaust pipes after you start it see if they warm evenly or if couple are colder than the others. Will narrow down the part of engine thats sick. Also check plugs clean replace, proably have done this, ok but may have fouled a couple. Stick with it really something very silly I bet.

 

No not the needles, the enrichment plungers. They sit on top on the rack, forward of the hats. Just move the choke to see what moves on the carbs. They have rubber boots on them, but you can take those off and then unscrew the plungers. Clean the plungers, clean their holes. And make sure to replace the rubber boots when you're done.

I'm still thinking float levels. As Fitz will tell you, Mikunis are picky.

 

It very well may be float levels. I won't get a chance to put the carbs back on the bike until this weekend, but come to think of it I did not break the carbs off the rack. Is there a detailed carb cleaning procedure someone could link? Since I have the carbs off already if breaking the rack is the only way to properly clean them I will do so.

 

It is and you will find few orings that may be the issue and is the proper way to clean go to xj4ever.com see there carb clinic post will show you basics bit plenty of other info out there on breaking the rack, google? Floats likely not issue will be lean, or rich bike will run. If floats set to high it would just flood bike with gas, only way could be the floats is if there set way to low not enough fuel going in, breaking the rack is a a little big deal but with preperation and lots of studying be a breeze u tube has a great video on this start to finish, after the video you will be more familar to this. I was right where you were at 1 month ago now I have a bike that eats cbrs for breakfast. Good luck. If I can help in any way message me, stick with it and you will be glad you did!

 

Also look at maxim4ever.com

 

I think you mean xj4ever.com

Otherwise you'll end up somewhere you might not want to be.

Dave

 

Yes that one sorry must be from all pot I used to smoke.

 

http://xjbikes.com/Forums/viewtopic/t=2 ... n+own.html

http://xjbikes.com/Forums/viewtopic/t=31061.html

http://www.xjbikes.com/Forums/viewtopic/t=14692.html

http://www.xj4ever.com/setting%20fuel%20levels.pdf

http://www.xj4ever.com/hitachi%20thrott ... 0seals.pdf

This should get you started. And ALL of your parts are with user name chacal (pm). Or at xj4ever.com.

 

Thanks a ton. One last thing before I gather materials for the weekend.. Will it be really obvious if shaft seals need replaced?

 

No it wont you will need to take apart, now you need to get a jap screw driver, dremmel, the screws are peened and will need to be cut off ground off. If you try to to remove them with out, well you will make it difficult find video on utube in the search type mikuni bs 33 rebuild theres an extensive 3 or 4 part video shos you how to remove screws you may damage. With preperation shouldnt be an issue.

 

After the u tube video and info from xj4ever.com you should become very familar with them, but if you would humor me for a second pull air box tits back from inlets of carbs, turn choke off, now grab a clean spray bottle put some gas in the spray bottle, now prime bottle, now open throttle wide open spray the gas close to inlets dosent have to carb at a time will get sucked in regardless, see if you can get it running, no choke on the bottle, if it starts this way throttle seals not your problem, dont think they are. Would be that throttle plates are not opening equally, also explain the high revs, well part of why, ounce bikes running and at a decent idle spray gas or carb cleaner around exterior of carbs by throttle shafts, if idle increases when this is done then you need to go into the detailed work. Let me know if this helps any, sound like pilot jet issues, also look on the bowls of the carbs you should see a stamp on little round nub mine said 35 this is jet size for your carbs if stock all jets in carb should read same number if they do not, could be problem. People go in asking for parts all the time guy at the counter dosent care usally, and if buyer dosent know could have wrong jets, issue I encountered. Food for thought.

 

Well, two of my carbs were high in level, two were spot on. I'm in the painful process of tang tweaking right now after making a makeshift gas tank and a PVC carb holder rack. Wish me patience..

 

Well all float levels are set. Anything else to do before putting them back on the bike?