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  • Con rod bolts

    anyone put blue loctite on the con rod bolts during reassembly. I don't have new bolts and nuts. I know the manual says to use new ones but but....?
    mack
    79 XS 1100 SF Special
    HERMES
    original owner
    http://i946.photobucket.com/albums/a...ps6932d5df.jpg

    81 XS 1100 LH MNS
    SPICA
    http://i946.photobucket.com/albums/ad305/mack-055/2.jpg

    78 XS 11E
    IOTA
    https://youtu.be/wB5Jfbp6SUc
    https://youtu.be/RaI3WYHSuWA



    Have recovery trailer and shop if you breakdown in my area.
    Frankford, Ont, Canada
    613-398-6186

  • #2
    Originally posted by mack View Post
    anyone put blue loctite on the con rod bolts during reassembly. I don't have new bolts and nuts. I know the manual says to use new ones but but....?
    Sounds good in theory, but imagine those are 'dry' torgue specs.
    A torque to spec. bolt/nut will stay tight.......overtorqued or undertorqued can loosen, but you already knew that.
    81H Venturer1100 "The Bentley" (on steroids) 97 Yamaha YZ250(age reducer) 92 Honda ST1100 "Twisty"(touring rocket) Age is relative to the number of seconds counted 'airing' out an 85ft. table-top.

    Comment


    • #3
      These

      bolts are discontinued according to yamaha. I don't want to buy off ebay and just get different USED bolts. Shame to put it all back together and throw a rod later, but , it is what it is I guess. Sure is getting hard to find the basic requirements for these bikes now. Glad for this site though. I can see in the future that lack of parts will be the end of them. What a shame.
      mack
      79 XS 1100 SF Special
      HERMES
      original owner
      http://i946.photobucket.com/albums/a...ps6932d5df.jpg

      81 XS 1100 LH MNS
      SPICA
      http://i946.photobucket.com/albums/ad305/mack-055/2.jpg

      78 XS 11E
      IOTA
      https://youtu.be/wB5Jfbp6SUc
      https://youtu.be/RaI3WYHSuWA



      Have recovery trailer and shop if you breakdown in my area.
      Frankford, Ont, Canada
      613-398-6186

      Comment


      • #4
        I wouldn't do it. Find the bolts. I've been following a CB750 build on YouTube and he had the same issue. He went with aftermarket con rods, but conceded he could get the bolts if he tried hard enough. Somebody has what you need to do this right. I wouldn't want the bike if I had any notion that it might throw a rod. I'm not a qualified machinist, but bolts that are meant to be stretched one time only, should be discarded to the circular file.

        Have you tried Speed & Sport in PA? Google "Yamatopdog".
        Marty (in Mississippi)
        XS1100SG
        XS650SK
        XS650SH
        XS650G
        XS6502F
        XS650E

        Comment


        • #5
          Fellas at ARP may be able to find you somthing if you contact them, JAT
          2H7 (79) owned since '89
          3H3 owned since '06

          "If it ain't broke, modify it"

          Comment


          • #6
            Searched

            I've spent the whole day searching, but no one had any. Looks like I'm going to have to reuse mine.
            mack
            79 XS 1100 SF Special
            HERMES
            original owner
            http://i946.photobucket.com/albums/a...ps6932d5df.jpg

            81 XS 1100 LH MNS
            SPICA
            http://i946.photobucket.com/albums/ad305/mack-055/2.jpg

            78 XS 11E
            IOTA
            https://youtu.be/wB5Jfbp6SUc
            https://youtu.be/RaI3WYHSuWA



            Have recovery trailer and shop if you breakdown in my area.
            Frankford, Ont, Canada
            613-398-6186

            Comment


            • #7
              Originally posted by mack View Post
              anyone put blue loctite on the con rod bolts during reassembly. I don't have new bolts and nuts. I know the manual says to use new ones but but....?
              Where are you finding this? I looked in the factory manual, and the only 'caution' I saw was one pertaining to torque. Nothing specific about replacing them.

              Generally speaking, you'll only run into 'one time' bolts/nuts under certain conditions, none of which apply here. Self-locking nuts, nuts/bolts with a factory-applied thread locker, or bolts where a specific amount of 'stretch' is desired (where the stretch is actually measured or torqueing to a number then turning the bolt a specified amount more) should be replaced, but any 'normal' bolt in good condition should last the life of the assembly if installed right.

              If it's peace of mind you're after, I suppose you could have yours magnafluxed for cracks. But if they look good and the nut/bolt thread fit is still tight, I wouldn't hesitate to reuse them.

              To be honest, rod failures due to bolts are rare. Far more occur from out-of-round big ends (with the bearing bore becoming egg-shaped over time) which is why resizing the rods is nearly always a part of a normal rebuild. Unfortunately, Yamaha doesn't give specs for what's acceptable here (or even what the nominal bore size should be) so you're left with the somewhat vague service manual procedure.
              Fast, Cheap, Reliable... Pick any two

              '78E original owner - resto project
              '78E ???? owner - Modder project FJ forks, 4-piston calipers F/R, 160/80-16 rear tire
              '82 XJ rebuild project
              '80SG restified, red SOLD
              '79F parts...
              '81H more parts...

              Other current bikes:
              '93 XL1200 Anniversary Sportster 85RWHP
              '86 XL883/1200 Chopper
              '82 XL1000 w/1450cc Buell, Baker 6-speed, in-progress project
              Cage: '13 Mustang GT/CS with a few 'custom' touches
              Yep, can't leave nuthin' alone...

              Comment


              • #8
                Crazy Steve does the research and saves the day, again! Good one!
                Marty (in Mississippi)
                XS1100SG
                XS650SK
                XS650SH
                XS650G
                XS6502F
                XS650E

                Comment


                • #9
                  I'll expand on the 'bolt stretch' thing....

                  Applying a specific torque to any bolt is designed to stretch the bolt a certain amount. Due to minor differences in manufacturing, you may not get the exact same stretch on every bolt. I know some race teams and high-end engine builders use the bolt-stretch method for rod bolts, but what they do is torque the bolt to attain a given amount of stretch, then compare this to the actual torque applied. If the bolt stretches at too low a number, it's replaced. Same for too high. Low means the bolt is soft, high it's hard. They're looking for a certain 'resiliency' as well as a very accurate clamping force (think of this a spring tension). These bolts can generally be reused if they meet specs.

                  Locking methods are generally used in clamping applications where there's more movement than the bolt stretch can compensate for. Different expansion rates (dissimilar metals), shock loading, flexing, all can be cause for additional locking being needed. But these also introduce a larger variation in the clamping force, so installing any sort of mechanical locking device where none were is a bad idea.
                  Fast, Cheap, Reliable... Pick any two

                  '78E original owner - resto project
                  '78E ???? owner - Modder project FJ forks, 4-piston calipers F/R, 160/80-16 rear tire
                  '82 XJ rebuild project
                  '80SG restified, red SOLD
                  '79F parts...
                  '81H more parts...

                  Other current bikes:
                  '93 XL1200 Anniversary Sportster 85RWHP
                  '86 XL883/1200 Chopper
                  '82 XL1000 w/1450cc Buell, Baker 6-speed, in-progress project
                  Cage: '13 Mustang GT/CS with a few 'custom' touches
                  Yep, can't leave nuthin' alone...

                  Comment


                  • #10
                    The torque on those bolts is only 28 Ft Lbs. That's not enough to stretch the bolts significantly, it's just enough to keep them from backing off.

                    I've built a lot of engines, all types, and reused the rod cap bolts as well as the main cap bolts without issue. And I'm not nice to ANY engine.

                    With that bolt stretch theory you would be replacing case bolts and head/cylinder studs every time you took it apart.

                    At 28 Ft Lbs I wouldn't hesitate a second reusing rod cap bolts. After all, they've already been tested in the real world.
                    Greg

                    Everybody is a genius. But if you judge a fish by its ability to climb a tree, it will live its whole life believing that it is stupid.”

                    ― Albert Einstein

                    80 SG Ol' Okie;79 engine & carbs w/pods, 45 pilots, 140 mains, Custom Mac 4 into 2 exhaust, ACCT,XS850 final drive,110/90/19 front tire,TKat fork brace, XS750 140 MPH speedometer, Vetter IV fairing, aftermarket hard bags and trunk, LG high back seat, XJ rear shocks.

                    The list changes.

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                    • #11
                      reference

                      I believe it was Haynes I read it in but it could be the FSM. I'll check tomorrow but I have to say I'm relieved. I'll give the page and para number but if you two say it's all good, that's good enough for me.
                      mack
                      79 XS 1100 SF Special
                      HERMES
                      original owner
                      http://i946.photobucket.com/albums/a...ps6932d5df.jpg

                      81 XS 1100 LH MNS
                      SPICA
                      http://i946.photobucket.com/albums/ad305/mack-055/2.jpg

                      78 XS 11E
                      IOTA
                      https://youtu.be/wB5Jfbp6SUc
                      https://youtu.be/RaI3WYHSuWA



                      Have recovery trailer and shop if you breakdown in my area.
                      Frankford, Ont, Canada
                      613-398-6186

                      Comment


                      • #12
                        Originally posted by mack View Post
                        I believe it was Haynes I read it in but it could be the FSM. I'll check tomorrow but I have to say I'm relieved. I'll give the page and para number but if you two say it's all good, that's good enough for me.
                        I think that torque-tensioning is most important when you have bolts with free lengths between the threads and the heads. I would think that with a lot of heating and cooling cycles (i.e. thermal expansion) you would want those types of bolts...like for the heads. Shorter bolts seem to depend more on lock washers, but I admit that I have never rebuilt one of these engines.
                        Skids (Sid Hansen)

                        Down to one 1978 E. Stock air box with K&N filter, 81H pipes and carbs, 8500 feet elevation.

                        Comment


                        • #13
                          reference

                          Here's where my concern came from:


                          Your right skids, the method to apply the torque to the nut is very specific in all the manuals. Once you start to turn, you can't stop at all until you hit the 28 ft/lbs. If you do miss it then you have to back it off about half way and start again.
                          mack
                          79 XS 1100 SF Special
                          HERMES
                          original owner
                          http://i946.photobucket.com/albums/a...ps6932d5df.jpg

                          81 XS 1100 LH MNS
                          SPICA
                          http://i946.photobucket.com/albums/ad305/mack-055/2.jpg

                          78 XS 11E
                          IOTA
                          https://youtu.be/wB5Jfbp6SUc
                          https://youtu.be/RaI3WYHSuWA



                          Have recovery trailer and shop if you breakdown in my area.
                          Frankford, Ont, Canada
                          613-398-6186

                          Comment

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