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Beginner restoration of a 82 XJ550 Maxim

Discussion in 'Hangout Lounge' started by Mancub, Mar 2, 2021.

  1. Roast644

    Roast644 Well-Known Member

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    The factory correct way is to synch with the YICS tool. But you can do it without blocking the YICS passages also. I don't know if its a 50/50 split in the way guys do it here, but many, many synchs have been done without it.

    I would suggest doing it without for the first time just to avoid the tool cost, get things running, log some miles....and then in a year if you are still a diehard XJ guy, buy the YICS tool and try it that way and decide which camp you fall into.
     
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  2. Dan Gardner

    Dan Gardner Well-Known Member Premium Member

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    The debate over whether or not a block off tool is necessary to do a carb sync has been raging for a long time.

    Lots of people say you don’t need it. I don’t know, but I have a tool and Yamaha says to use it, so I do.

    In your case, I think it would be fine to proceed without it. It is not something that is going to make it break the build. Worst case Ontario you will need to re-do it at some point. Not a huge deal.
     
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  3. Mancub

    Mancub Member

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    Thanks guys, that's the type of wisdom I needed. I just didn't want to do something that will ruin or be the reason the bike won't run right. I get that might be the way to get it more exact, but good to hear that's down the road as I decide how much of a "diehard XJ guy" I wanna be.

    Exciting! Last night I checked the valve clearances again. They are good. So now I'm hoping to mount those carbs, do a quick oil&filter change while I'm at it just to be safe (I think the leaky needle seats might have let gas into places). Now with the brakes done, tires, carb rebuilt and CLEAN, bench sync and wet set done.... I hope this thing runs like it's supposed to, I've never seen that yet. Always had some issue so far in this restoration.

    Question, the vacuum sync tool is still on it's way, would you guys say it's cool to ride around on it while I wait for that to come? Or should I wait till then because the idle/running/whatever is going to be off or hurting something until I do sync it?
     
  4. Roast644

    Roast644 Well-Known Member

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    If you do a careful bench synch, and start it up and it idles, responds to small changes in the idle screw (the big horizontal adjuster between #2 & #3), responds evenly to changes in the choke lever, and all 4 are firing at idle (check the exhaust headers for heat) then its as close as you can get without the vacuum gages. Then absolutely go ride. You won't damage anything.

    Typically though before synching you get erratic idle, poor choke response, missing etc. Tiny changes in the butterfly don't mean that much at half open, but if you can't get it to idle its not very enjoyable to ride. I wouldn't say you'd damage anything like this, but your poor starter might get a workout.

    Vacuum synching can feel magical sometimes, going from "Holy crap this engine is shot" to "Purrs like a kitten" with a tiny twist of the screw.
     
  5. Mancub

    Mancub Member

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    How exciting, I dream of it purring haha Sounds good. Thank you.

    Surely I'll be back here soon. I should get an award on consistent effort over time for a newbie haha
     
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  6. Mancub

    Mancub Member

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    Good news after a rebuild haha I can fire it up! I need some tips though.

    Manual says to get the bike using the idle screw to around 1200 rpm before you start adjusting... well I'm having a hard time getting it to sit steady at 1200 on idle. How much do you have your idle screw in typically? I started with it at none, and feel like I've added quite a bit.

    I've had a few spikes in rpms as I'm putting choke and no choke just to try and start it up. @Roast644 your right I would give my starter a workout I can see that. I'm hoping all i'm facing is not being synced right. I'm trying it on a digital 2 port. I just can't get it steady enough without giving it throttle to stay alive to really get any good results...

    Anyways, tips on how to get it right. Do you leave a little choke to just keep it running and begin the balance? Is there something else happening? Seems odd. My carbtune doesn't come for a week so I I'd like to get it somewhat balanced as I wait. But yeah... can't get it stable enough to sync. The bench synce was a pretty dang close on a paper clip end just as a heads up.
     
  7. Roast644

    Roast644 Well-Known Member

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    The 2 port vacuum gage you are using is digital? I haven't seen one like that but I can imagine that makes it really difficult. Typically on an analog gage the needle is bouncing and you use the needle valve to quiet it down, but still might have to split the difference.

    It sounds like you're experiencing typical issues that the sync will resolve. Maybe somebody here uses digital gages and has some tips for you.
     
  8. Dave in Ireland

    Dave in Ireland Well-Known Member

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    A digital gauge using the vacuum pipery will respond to clamping the pipe, exact same way as an analogue gauge.
    Aquarium air pipe clamps.
     
  9. Mancub

    Mancub Member

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    I think I'm just going to have to do the analog, the digital (even with the claps is jumping around)

    However. If you can't get it to idle around 1200 before syncing do you just start doing a little bit even with a little choke or something and then bring it down, and just keep running the cycle till it works?
     
  10. Huntchuks

    Huntchuks Well-Known Member

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    Syncing should be done with a warmed up (hot) engine with no enrichment, I believe.
     
  11. Mancub

    Mancub Member

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    Yeah I can see that ideally you have it warmed up and idling with no choke at like 1200 before you do the final sync.

    I'm just struggling to get it stable and idling at 1200 to start, so I'm thinking I might have to tweak some to get it closer and then eventually resync it once I can get it to idle with no choke, then I can do the final.
     
  12. Mancub

    Mancub Member

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    Hey guys! Well it's been about a month I've actually be riding the bike around, to and from work, it's working! hah what a journey.

    Now I'm starting to think of what's next, and noticing some things that aren't working right or need help.
    1. I noticed for some reason that the blinkers aren't working right... I redid the fusebox, and I did notice that before they had bypassed the box and just butted the signals line. Not sure what changed there.
    2. My exhaust pipe has some holes in it, I can feel little puffs of air. Are there ways to repair that, is it a replace thing, or is it a don't worry about it thing
    3. Riding around is stiff and rattley as could be, guessing that back shock is not doing much.
    4. I have an oil leak I think from the head plate, the gasket seemed ok when I was in there, I'm thinking it might be that those pressure washers on the inside and out are flat.
     

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