1978 750 XS Special

Discussion in 'Old's Cool' started by Krantz, Oct 19, 2013.

  1. Krantz

    Krantz OMG aka WTF

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    Yep! That stinker is driving me crazy and scared my cat ! One carb is more or less is clear. the other two are still submerged.They are like siameese twins- refuse to separate.
    Coupla days ago i was driving from somwhere,coming back home,when on the next over street to my house i saw- right out of the corner of my eye a bright spot.Would not you know it- Yamaha RD 350 in someone's driveway.Turns out a neighbor called a mechanic to work on his car, and the guy comes on a motorcycle.So i pull up, point to the bike and they start laughing.This thing is like a bright light to the moth.He says -yep!So we talk a little and i asked him where he goes for parts.He tells me -surprise- local Yamaha dealer! And that is what i did today- took my brake lines to them, they can make a new ones in braded steel.Also ordered carb kits,brake caliper kits,master brake cyl.kit and something else.All available! Same price as online places.

    Some things i can't remove -my rotor- need puller for that,might have it in my garage.
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    #41
  2. Krantz

    Krantz OMG aka WTF

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    About the metal in the oil pan- my thoughts it is a piece of the kickstart. I'll get to it when i pull the rotor.
    Fuel tank is undergoing classical treatment of vinegar marinading.Hope it will be done soon.It is the only part on the bike that i consider repainting.Maybe different color.But that's later.

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    I want to pull the head off,but it's not as simple as airhead.From what i read about it there is a master link in the cam chain.Anyone knows how to unlock it?Or even how it looks like?
    #42
  3. concours

    concours WFO for 50 years

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    IIRC, they were one-time, expand the hollow rivets to install. You should be able to remove the sprockets from the end of the cams, and leave the chain connected. Be SURE you run through the cam timing procedure BEFORE you dismantle, so you are sure the timing marks are as expected, shown in the book. :deal
    #43
  4. Krantz

    Krantz OMG aka WTF

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    Quote
    IIRC, they were one-time, expand the hollow rivets to install. You should be able to remove the sprockets from the end of the cams, and leave the chain connected. Be SURE you run through the cam timing procedure BEFORE you dismantle, so you are sure the timing marks are as expected, shown in the book. :deal
    Thanks! I read somewhere that it is possible to stick a piece of plastic under the cahin to slide it off.There is enough of a slack in it after i released the tensioner.
    And about these: will i ever get it right? They cleaned up nicely in pine-sol.I'm just waiting for the kit to arrive.

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    #44
  5. Rob Farmer

    Rob Farmer Long timer

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    I rebuilt an early fj1100 last year and was pleasantly surprised at the parts availability and prices at the local Yamaha dealer. They also, obviously, stock the yamlube range of oils that has all the grades of oils I use in my airhead forks and gearboxes.. Good prices as well.
    #45
  6. Krantz

    Krantz OMG aka WTF

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    Yes, Yamaha dealer was a surprise! Although i suspect a lot depends on who's behind the counter. For instance i wanted to buy a tube of honda moly- you know what i'm talking about.In one dealership they told me they do not have it , cause it's expensive.I said fine, can you order it for me? No. Ok, i went to more friendly place and they did.
    #46
  7. concours

    concours WFO for 50 years

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    remember to blow out ALL passages in those carbs, and then VERIFY flow with a spray can of Brakleen or the like.
    #47
  8. Krantz

    Krantz OMG aka WTF

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    The mistery continues.Today i pulled the rotor and was able to remove right side engine cover. Everything looks clean.I looked very carefully at the kickstart gear-no broken teeth! And the one i found in the oil pan is a quite smaller.While i did that, i tried to turn the engine by kickstart- there is alot of resistance.But if i put crescent wrench to the crank-( see where the bolt on the right side is?) it goes a lot easier.So my thinking- this is something in the tranny.Maybe the engine was never seized in the first place-i just never tried to turn it by taking a wrench to the crank.



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    #48
  9. concours

    concours WFO for 50 years

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    E-start gear tooth?
    #49
  10. MacNoob

    MacNoob piney fresh

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    While wearing goggles/face shield, as spraying yourself in the face with strong chemicals is no fun at all.
    #50
  11. Krantz

    Krantz OMG aka WTF

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    Worked a little bit on the bike today.Took the ignition module off,then left side engine cover.Again, just like on the right side,alltogether it looks clean.



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    However-take a look at the starter clutch-here is the evidence of that broken tooth,found in the oilpan:



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    And the funniest part is that if you take a measure of that tooth against anything on this side, it does not fit anywhere.There is only one place i did not looked at -1st gear.It is under the small cover on the left side. And it's a long way for it to get to the starter clutch.So this breakdown is somewhere in the tranny.Starter clutch is working fine.
    #51
  12. concours

    concours WFO for 50 years

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    split it
    #52
  13. bmwhacker

    bmwhacker Still on 3 wheels

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    MONTANA NATIVE from NATIVE MONTANA
    :lurk
    I love mysteries & suspense.....:D

    Had an XS 850 Special triple back in the day. It was a great bike.
    #53
  14. concours

    concours WFO for 50 years

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    Perhaps a starter gear tooth busted off previously and was replaced? They dinged parts were deemed serviceable, the broken one replaced?
    #54
  15. Cletus Runswithscissorsguy

    Cletus Runswithscissorsguy hiding in plain sight

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    IIRC, those were notorious for blowing up 1st and 2nd gear. Under 'normal' use they are fine, but second gear wheelies make them go crunch...
    #55
  16. waveydavey

    waveydavey happy times!! Supporter

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    There was a shifter detent plate on my 1979 XS750 that used to come loose when a circlip would come off. When that happened I would not be able to shift into second gear. Once I fixed it the first time it became quite easy to do, so I would lay the bike on its side in some grass and remove the cover (did not lose my oil that way), then put the circlip back on. It was about a 15 minute fix. I was not very nice to that bike, but it never left me stranded. :lol3
    #56
  17. Krantz

    Krantz OMG aka WTF

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    How time flys!jus re-read my thread-did write all that?
    Anyway, not much was done to the bike,mainly due to business being so tough-not a penny to spare.However,things might turn around.So i'm looking at it again.And could someone please say something inspiring?
    About that broken tooth-it's an alien. Does not belong anywhere here.origin unknown.All gear teeth are ok,nothing is broken.I may newer know,how this one got here.
    So the corse of action is this-i have a line on another one of this to look at-seller says it runs.I've been looking for spare parts and what makes economical sense is to get another one in decent shape,and just swap engines.If i could get it reasonably cheap-party on! Will keep you posted.
    #57
  18. Krantz

    Krantz OMG aka WTF

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    Resent trip to a nearby town resulted in this:

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    One might say I have a hoarding problem.
    However- the red one has running engine with presumably 33K kilometers.Front brakes are somewhat present,rears are dead.Needs new tires.Found couple of new Kenda tires at about 110$.Sounds like a good deal.
    The blue one has no papers and will serve as an engine donor for the first special- the engine turns,got good compression.So the plan is to make 2 out of three. Do not need to do much to the red one,just brakes,tires and possibly electric gremlins.One can say "I've heard that before".Ok, go ahead, critisize.


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    #58
  19. scmopar

    scmopar Been here awhile

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    Cool glad your back .

    sent using #2 pencil
    #59
  20. Krantz

    Krantz OMG aka WTF

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    Meanwhile we are getting ready for heart transplant:

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    stuff that i ordered starts showing up at my door- that"s careless Fedex delivery.Yep. Just drop it off at my porch. No one is interested.Just new tires.
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    #60