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  • Noob engine help

    So I have my motor out right now and before I do anything rash I thought I'd get some advice.
    My motor ran, poorly(chewed oil and had oil on the plugs), but it ran. Obviously oil isn't staying where it needs to be and it really needs some love and tender touching after all these years of who knows what's happened to it.

    However, I've never "rebuilt" a motor before and this isn't exactly starting small. I have the manual, plenty of resources on the web, and even found a YouTube of someone replacing the rings. Is this something I can do on my own or am I barking up a big tree?
    80G

  • #2
    My thought is follow the disassembly process from a manual and go from there. Most likely the problem is in the rings or maybe valve guide seals.
    Howard

    ZRX1200

    BTW, ZRX carbs have the same spacing as the XS11... http://www.xs11.com/forum/showthread.php?t=35462

    Comment


    • #3
      Originally posted by AggiesaurusRex View Post
      So I have my motor out right now and before I do anything rash I thought I'd get some advice.
      My motor ran, poorly(chewed oil and had oil on the plugs), but it ran. Obviously oil isn't staying where it needs to be and it really needs some love and tender touching after all these years of who knows what's happened to it.

      However, I've never "rebuilt" a motor before and this isn't exactly starting small. I have the manual, plenty of resources on the web, and even found a YouTube of someone replacing the rings. Is this something I can do on my own or am I barking up a big tree?
      Well, to bad you didn't do a compression test before pulling motor. Either way, and with help here as needed, I'd pull the head, as it is likely valve guide seals are shot and some may even be laying in the oil pan. Pulling cyl. jugs off to replace rings may not even be necessary, depends what cyl. wall look like with head off. Most likely just re-facing valves and seats of head will solve the oil getting in cyls. issue. Other than that, this is something I'm sure your capable of. Inquire HERE for the help and any questions.....definitely don't try using anything off YouTube....that'll just give you who knows what kind of problems. Only CORRECT help will be found here from links here, or asking here. We're glad to help someone....... doing it correctly. I'm sure a few others will chime in with more detailed advice also .
      Last edited by motoman; 02-17-2017, 01:07 PM.
      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


      • #4
        I did compression test and it revealed 135/120/115/130.
        The YouTube was Andy's Motorcycle Obsessions and he's posted an entire informative build series of some 50 videos of odds and ends for his xs11 and is on the XS11 Australian forums. He seems like he has done his research and isnt just "some youtube guy".
        80G

        Comment


        • #5
          How long had the bike been sitting before you got it? how many miles did you put on it? How hard did you ride it?
          These are three IMPORTANT questions to ask BEFORE doing anything with the XS11. A lot of these have sat for one to ten years, and show low compression even though they have only 20K or so miles on them. Running the bike for about a thousand miles will fix a lot of the problems with oil consumption.
          As the engine is out, pull the head and replace the valve seals. I would also flip it over and do the second gear fix, just because it's a known weak point.
          Rings are getting hard to find, but can be had. If you have a score or something in the bore, then it will be an overbore kit, and have a machine shop do work for you, about $250 for me local.
          Ray Matteis
          KE6NHG
          XS1100 E '78 (winter project)
          XS1100 SF Bob Jones worked on it!

          Comment


          • #6
            Might I suggest looking for a donor engine? I have three or four just for that purpose, just in-case this guy goes on me.
            1979 XS1100F
            2H9 Mod, Truck-Lite LED Headlight, TECHNA-FIT S/S Brake Lines, Rear Air Shocks, TKAT Fork Brace, Dyna DC-I Coils, TC Fuse Block, Barnett HD Clutch Springs, Superbike Handlebars, V-Star 650 ACCT, NGK Irridium Plugs, OEM Exhaust. CNC-Cut 2nd Gear Dogs; Ported/Milled Head; Modded Airbox: 8x8 Wix Panel Filter; #137.5 Main Jet, Viper Yellow Paint, Michelin Pilot Activ F/R, Interstate AGM Battery, 14MM MC, Maier Fairing, Cree LED Fog Lights.

            Comment


            • #7
              What I would do

              If the main bearing weren't making any knocking noise, then you should be satisfied to replace the rings and (lightly) lap the valves.

              I would measure the cylinder walls first. They wear into an hourglass shape perpendicular to the wrist pins.

              If the cylinder dimensions are in spec, new STD rings are easy to find and inexpensive. You can use a ball hone easily, and replacing the rings is easy.

              If you find the cylinder walls are out of spec, then you have to find new pistons and new rings, so you are better off to find a kit. Like DiverRay said, most everyone would need to go to a machine shop to bore it out.

              Lapping the valves is easy, but you need a valve spring compressor to remove the valves. You can buy one for $35-50 US, or some folks have made them from a clamp and ratchet socket. You can search for posts.

              The valve seals are easy to find, and easy to replace once the valves are out. They only cost a few US dollars each.

              These items will get you back to stock compression and negligible oil consumption.
              -Mike
              _________
              '79 XS1100SF 20k miles
              '80 XS1100SG 44k miles
              '81 XS1100H Venturer 35k miles
              '79 XS750SF 17k miles
              '85 Honda V65 Magna ~7k miles
              '84 Honda V65 Magna 48k miles (parts bike)
              '86 Yamaha VMAX 9k miles

              Previous: '68 Motoguzzi 600cc + '79 XS750SF 22k miles +'84 Honda V65

              Comment


              • #8
                How long had the bike been sitting before you got it? how many miles did you put on it? How hard did you ride it?
                These are three IMPORTANT questions to ask BEFORE doing anything with the XS11. A lot of these have sat for one to ten years, and show low compression even though they have only 20K or so miles on them. Running the bike for about a thousand miles will fix a lot of the problems with oil consumption.
                As the engine is out, pull the head and replace the valve seals. I would also flip it over and do the second gear fix, just because it's a known weak point.
                Rings are getting hard to find, but can be had. If you have a score or something in the bore, then it will be an overbore kit, and have a machine shop do work for you, about $250 for me local.
                It wasn't sitting as far as I know, it was being used regularly. I barely touched it, I put maybe 10 miles on it. They were not hard miles at all, I was just skipping down the road behind the shop. As of now its been sitting for near on 11 months. I have no speedo cluster so no idea what the actual mileage is or what state anything is at.

                Might I suggest looking for a donor engine? I have three or four just for that purpose, just in-case this guy goes on me
                I'd hate to buy another whole engine when it may or may not be in the same shape and the cost of another engine would be just as much as taking care of this one and knowing its set.
                80G

                Comment


                • #9
                  Originally posted by motoman View Post
                  (snip) Most likely just re-facing valves and seats of head will solve the oil getting in cyls. issue. (snip)
                  Brant, I don't see how that can prevent oil loss. It would probably increase compression though.
                  Skids (Sid Hansen)

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

                  Comment


                  • #10
                    Originally posted by AggiesaurusRex View Post
                    I did compression test and it revealed 135/120/115/130.
                    Hey there Rex,

                    First, just want to ask how you did the compression test, because some folks don't know that you're supposed to have the throttle cracked wide open so there's no restriction of airflow into the engine. And so if you didn't have the throttle wide open, then your readings could be artificially low. But if you did do it correctly, then they are still not that bad. Stock is stated to be 142+/-10psi at sea level. And the 115 one is just a little more than 10% off from the 130 ones, so not that bad.

                    As was stated, low comps is often just due to inactivity, gummed/stuck rings and such, and running the engine many hundred miles helps to loosen the rings and reseat them. Also, low comps can also be due to the valve clearances not set to spec. And what was stated about doing a good valve job, replacing the seals, and lapping the valves will stop oil from getting in from the valves and will help boost compression levels as well.

                    SO....if you have the gauges, check the cylinders for oval wear, but if within specs, you may want to do a very light honing, OR...just put the head back on, and get it running, use a little Marvel Mystery Oil in the oil to help break up gum/varnish and loosen the rings, and then put several hundred miles on it, and then recheck the compression levels, and you'll probably find them back up close to stock and within 10% of each other.

                    T.C.
                    T. C. Gresham
                    81SH "Godzilla" . . .1179cc super-rat.
                    79SF "The Teacher" . . .basket case!
                    History shows again and again,
                    How nature points out the folly of men!

                    Comment


                    • #11
                      Originally posted by AggiesaurusRex View Post
                      I did compression test and it revealed 135/120/115/130.
                      The YouTube was Andy's Motorcycle Obsessions and he's posted an entire informative build series of some 50 videos of odds and ends for his xs11 and is on the XS11 Australian forums. He seems like he has done his research and isnt just "some youtube guy".
                      Sorry, as you didn't specify location of info. The Aussi folks are actually fairly sharp on these ole' scoots.
                      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


                      • #12
                        Originally posted by skids View Post
                        Brant, I don't see how that can prevent oil loss. It would probably increase compression though.
                        Definitely can, if that's the issue. Valve guide seals hardened badly or just plain gone guarantee will suck oil by into cyls. Just was my initial thoughts that may possibly save him a lot of unnecessary work. since I'd previously yrs. back been seriously involved with high performance engine building, (cam profiles matched to intake exhaust profiles,etc.), and have the wins to prove it from NHRA sanctioned races at the drag-strip. Not braggin'......just sayin' buddy.
                        Last edited by motoman; 02-17-2017, 08:43 PM.
                        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


                        • #13
                          Originally posted by motoman View Post
                          Definitely can, if that's the issue. Valve guide seals hardened badly or just plain gone guarantee will suck oil by into cyls. Just was my initial thoughts that may possibly save him a lot of unnecessary work. since I'd previously yrs. back been seriously involved with high performance engine building, (cam profiles matched to intake exhaust profiles,etc.), and have the wins to prove it from NHRA sanctioned races at the drag-strip. Not braggin'......just sayin' buddy.
                          OK, but you said, "Most likely just re-facing valves and seats of head will solve the oil getting in cyls. issue."
                          Skids (Sid Hansen)

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

                          Comment


                          • #14
                            It wasn't sitting as far as I know, it was being used regularly. I barely touched it, I put maybe 10 miles on it. They were not hard miles at all, I was just skipping down the road behind the shop. As of now its been sitting for near on 11 months.
                            As the engine is out, I would get a complete gasket set for it, and pull the head, measure the cylinders, and do a valve job on it. If cylinders are good, it will cost about $100 for everything if you do it yourself. The gasket kit will have new valve seals, and new "O" rings for the jugs if you do need to bore it. Head gasket it about $50, set is about $80....
                            Should take about 8 hours max to get the valves done(if it's your first time), so not that much time as you can work in a garage, or even inside to pull apart and put together if you have someplace you can put down a bit of plywood to keep things from getting oiled up.

                            Read through the repair sections here, and you will have a better idea of how easy it really is. Big thing is DO NOT INSTALL BOTH CAMS AT ONCE AND THEN TURN ONLY ONE!! The valves WILL bend if you do it wrong! IT's really not hard, but do read how so you understand the workings before you start.
                            Ray Matteis
                            KE6NHG
                            XS1100 E '78 (winter project)
                            XS1100 SF Bob Jones worked on it!

                            Comment


                            • #15
                              Originally posted by skids View Post
                              OK, but you said, "Most likely just re-facing valves and seats of head will solve the oil getting in cyls. issue."
                              Tie that in with associated statements referring the guide seals so assumed,obviously the valve guide seals would be replaced.....pretty simple.....'taint rocket science.
                              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

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