Loading ...
Sorry, an error occurred while loading the content.
 

Re: Aermacchi cam failure

Expand Messages
  • Greg Summerton
    David, I ve only had abnormal cam follower wear failure on race engines once. That was the result of ignorant-me tying to run cams with lift rates that were
    Message 1 of 24 , Feb 1, 2007
      David,
      I've only had abnormal cam'follower wear failure on race engines once.
      That was the result of ignorant-me tying to run cams with lift rates
      that were too high for the diameter of the round flat followers...the
      cams were simply running off the edge of the followers, wiping oil from
      the contact surfaces and having almost point contact with resultant high
      contact pressures per area and no oil to speak of. Elementary, but not
      obvious to me until I wrecked two sets of cams and followers!

      Not saying this is the problem here though, but I have seen a set of
      rockers that were second hand, previously used with standard cams, but
      were pressed into service with a new hot cam.
      Fortunately(!) the engine had another failure and was stripped down but
      bad war was evident and the cam and rocker contact area. THe old rocker
      had worn the edges of its contact area to the std cam but was only
      running on it's edge for the first and last part of the lift with the
      new cam.

      All I am saying here is to ensure that you do not perhaps have a mix of
      parts that run to the edge of contact surfaces......as possibly the
      XT500 Yam pic might be showing? That insert has a sharp edge with no
      real lead in at the unworn end....?
      But of course we cannot see the starting shape of the edge of the rocker
      inserts on the leading edge anymore.

      I also raced 500 Yams. Mine were raced in English-style dirt track and
      long track. They ran huge lift cams, had big valves, hairy springs and
      ran a full 14:1 CR on meths and were a match for the early Jawa and
      Weslake 4 valvers, unless they were ridden by the top few riders....
      I have seen bad cam and follower wear on Yams with an oil flow fault,
      but never experienced catastrophic wear on my engines.
      I lubed new cams with the tube of moly-stuff that came with the cams
      when new, but did not do this always.
      But then of course I ran castor oil 40w in EVERY alky engine I've ever
      raced.
      That stuff is good.
      When Castrol here in Oz stoppedselling it I rang their techo guy and
      asked what was the recommended replacement.
      He talked a bit and mentioned product, but I asked if any of it has the
      same load bearing capability (or whatever the correct technical term is)
      and he told me that none of what they supply can match the castor oil.
      I thanked him.
      I now use Rock Oil Castor 40w.

      I don't know if that is the full story on oils, but after Castrol
      admitted that, why would I use anything else?
      My experience seems to bear this out, I've had good wear rates in all my
      race engines over the years.
      I would never run any highly loaded old non-Jap race engine on anything
      else.

      I guess I've lit the oil-fuse now.....lol...hope not.
      So check the fit of the follower to the cam and make sure it is not
      running right to the edge of contact before you go too far.
      Greg
    • davidfallon441
      ... Hans; I guessed it was cast iron in the form of Ductile which I know some call cast steel. It is an exact match for the original stock cam, so I assume it
      Message 2 of 24 , Feb 1, 2007
        --- In mc-engine@yahoogroups.com, "hans_o_man" <der_hiha@...> wrote:
        >
        > Hi David,
        > tell me more about the cam-material. I guess it isn't cast-iron, but
        > steel?

        Hans;

        I guessed it was cast iron in the form of Ductile which I know some
        call cast steel. It is an exact match for the original stock cam, so
        I assume it was made in the mother country of Italy. It was an NOS
        part still in the factory packing too. This is just the plain old
        street motor with modest power.

        The info about the cams and lifter is good. I did not know that the
        lifters require a radius ground into the contact surface. That could
        be what the problem is. I used sandpaper on a flat granite plate to
        get the contact surface flat, smooth and shiney. That sounds like the
        wrong thing to do.

        Crane also has lot of good info about cams and startup, though they
        never mentioned about the radius on the lifter contact point.

        It hurts my wallet to see the picture of the Yam 500 cam and lifters.

        I did use the Bel Ray moly cote for engine building. I know moly is
        your friend when it comes to high pressure. I also could and did
        prime the whole oil system backwards by using a handy external line
        that goes up to the cylinder head. The engine got a push start and
        started right up to, so I got all those parts right.

        I'm not acquainted with Parkerizing. Is it the do it yourself option?

        David Fallon
        WMRRA 441
      • davidfallon441
        ... Thanks Greg; Even though this is a stock set up, I need to look at the contact point too. With this bike it is very out in the open and easy to see, so
        Message 3 of 24 , Feb 1, 2007
          --- In mc-engine@yahoogroups.com, Greg Summerton <gregss@...> wrote:

          >
          > I guess I've lit the oil-fuse now.....lol...hope not.
          > So check the fit of the follower to the cam and make sure it is not
          > running right to the edge of contact before you go too far.
          > Greg
          >
          Thanks Greg;

          Even though this is a stock set up, I need to look at the contact
          point too. With this bike it is very out in the open and easy to see,
          so I'll check that.

          Oil wars, there always interesting, and I hesitated to mention what I
          had used.

          David Fallon
          WMRRA 441
        • hans_o_man
          Hi David, ... Don t bother, the worst work was cleaning the engine from debris :-) The cam was built by myself, and the rockers are repaired by grinding off
          Message 4 of 24 , Feb 1, 2007
            Hi David,
            >
            > It hurts my wallet to see the picture of the Yam 500 cam and lifters.
            >
            Don't bother, the worst work was cleaning the engine from debris :-)
            The cam was built by myself, and the rockers are repaired by grinding
            off the hardblock, hardwelding and regrinding. For I can do that
            myself, ist's not a wallet-, but a time problem...

            For pre-lubrication I use the redline assembly lube
            http://www.racerpartswholesale.com/redline10.htm
            >
            > I'm not acquainted with Parkerizing. Is it the do it yourself option?
            >
            I didn't try to parkerize myself, but galvanic shops(?) do that.
            Its also called manganese-phosphating and many OEM-cams are treated
            that way.

            Gruss
            Hans
          • Michael Moore
            David, another thing you can do to prime the engine is before starting it (in the bike) remove the plugs and engage low gear and push it around until you see
            Message 5 of 24 , Feb 2, 2007
              David, another thing you can do to prime the engine is before
              starting it (in the bike) remove the plugs and engage low gear and
              push it around until you see signs of oil circulation. You probably
              only really need to do that before the first start of the day.

              I've heard the people at Megacycle Cams refer to "Italian mystery
              cam steel" and they seemed unenthusiastic about hard-welding on
              OEM Italian camshafts due to problems with (I think) cracking.

              cheers,
              Michael
            • davidfallon441
              ... Thanks Michael; The note about the mystery steel is very interesting as the Megacycle folks would have lots of experience with that sort of issue. David
              Message 6 of 24 , Feb 2, 2007
                --- In mc-engine@yahoogroups.com, "Michael Moore" <mmoore@...> wrote:
                >
                > David, another thing you can do to prime the engine is before
                > starting it (in the bike) remove the plugs and engage low gear and
                > push it around until you see signs of oil circulation. You probably
                > only really need to do that before the first start of the day.
                >
                > I've heard the people at Megacycle Cams refer to "Italian mystery
                > cam steel" and they seemed unenthusiastic about hard-welding on
                > OEM Italian camshafts due to problems with (I think) cracking.
                >
                > cheers,
                > Michael
                >
                Thanks Michael;

                The note about the mystery steel is very interesting as the Megacycle
                folks would have lots of experience with that sort of issue.

                David Fallon
                WMRRA 441
              • Ian
                ... There is always arguments over what oil to use, the next hottest subject to get into an argument over is whether to use a pre-lube during assembly. The
                Message 7 of 24 , Feb 2, 2007
                  >For pre-lubrication I use the redline assembly lube
                  ><http://www.racerpartswholesale.com/redline10.htm>http://www.racerpartswholesale.com/redline10.htm


                  There is always arguments over what oil to use, the next hottest
                  subject to get into an argument over is whether to use a
                  "pre-lube" during assembly. The best engine builders I know
                  are divided on this, and if they can't agree then I'm not going to
                  express an opinion.



                  Cheers IAN


                  See www.drysdalev8.com for :
                  - Drysdale 750-V8 Sports & 1000-V8 Cruiser
                  - DRYVTECH 2x2x2 Experimental
                  - Carberry Enfield 1000cc V-Twin
                  - Drysdale Hillclimb Open Wheeler


                  --
                  No virus found in this outgoing message.
                  Checked by AVG Free Edition.
                  Version: 7.1.411 / Virus Database: 268.17.20/664 - Release Date: 2/2/2007
                • davidfallon441
                  ... Ian; I do love a heated discussion as long as it sheds a few grains on knowledge on the subject. I usually do not participate myself, but I love to
                  Message 8 of 24 , Feb 2, 2007
                    --- In mc-engine@yahoogroups.com, Ian <iwd@...> wrote:
                    >
                    >
                    > >For pre-lubrication I use the redline assembly lube
                    >
                    ><http://www.racerpartswholesale.com/redline10.htm>http://www.racerpartswholesale.com/redline10.htm
                    >
                    >
                    > There is always arguments over what oil to use, the next hottest
                    > subject to get into an argument over is whether to use a
                    > "pre-lube" during assembly. The best engine builders I know
                    > are divided on this, and if they can't agree then I'm not going to
                    > express an opinion.
                    >
                    >
                    >
                    > Cheers IAN

                    Ian;

                    I do love a heated discussion as long as it sheds a few grains on
                    knowledge on the subject. I usually do not participate myself, but I
                    love to observe.

                    David Fallon
                    WMRRA 441
                  • hans_o_man
                    I only wanted to say: [Redline-lube] It worx for me...:-)
                    Message 9 of 24 , Feb 4, 2007
                      I only wanted to say: [Redline-lube] It worx for me...:-)
                      >
                      > There is always arguments over what oil to use, the next hottest
                      > subject to get into an argument over is whether to use a
                      > "pre-lube" during assembly. The best engine builders I know
                      > are divided on this, and if they can't agree then I'm not going to
                      > express an opinion.
                      >
                      >
                      >
                      > Cheers IAN
                    • Michael Bateman
                      Another question - Has anyone experimented with crankshaft balance factors other than 50% for the SV650? And - in figuring the bobweights are you including an
                      Message 10 of 24 , Feb 11, 2007
                        Another question -

                        Has anyone experimented with crankshaft balance factors other than 50% for
                        the SV650? And - in figuring the bobweights are you including an amount for
                        the oil in the crank or are you ignoring it?

                        Also -

                        Is there any reason why a pressed together crank with captured rods (ie
                        Honda 160 etc) can't be balanced statically with the rods in place by
                        hanging appropriate weights from the rod ends while on either a knife edge
                        fixture or a nice fabricated low friction balance rig? I'm sure all of this
                        was figured out in the '40s and I'm just now catching up... :-) Based on
                        my reading of Honda's tech papers from the '60s we tend to relearn an awful
                        lot of stuff that's been known for years.

                        Cheers!

                        Michael

                        --
                        No virus found in this outgoing message.
                        Checked by AVG Free Edition.
                        Version: 7.5.441 / Virus Database: 268.17.33/678 - Release Date: 2/9/2007
                        4:06 PM
                      • Ian
                        ... A 90 deg vee twin has zero primary vibe at 50% BF, why would you want anything else ? ... No reason, you can get them pretty close with a bit a practice.
                        Message 11 of 24 , Feb 12, 2007
                          >Has anyone experimented with crankshaft balance factors other than 50% for
                          >the SV650?


                          A 90 deg vee twin has zero primary vibe at 50% BF, why
                          would you want anything else ?


                          >Is there any reason why a pressed together crank with captured rods (ie
                          >Honda 160 etc) can't be balanced statically with the rods in place by
                          >hanging appropriate weights from the rod ends while on either a knife edge
                          >fixture or a nice fabricated low friction balance rig?


                          No reason, you can get them pretty close with a bit a
                          practice.



                          Cheers IAN



                          See www.drysdalev8.com for :
                          - Drysdale 750-V8 Sports & 1000-V8 Cruiser
                          - DRYVTECH 2x2x2 Experimental
                          - Carberry Enfield 1000cc V-Twin
                          - Drysdale Hillclimb Open Wheeler


                          --
                          No virus found in this outgoing message.
                          Checked by AVG Free Edition.
                          Version: 7.5.441 / Virus Database: 268.17.36/681 - Release Date: 2/11/2007 6:50 PM
                        • Michael Bateman
                          ... Thanks Ian - I guess a better way to ask that question would have been whether or not there s any reason to think of a balance factor other than 50%. I
                          Message 12 of 24 , Feb 12, 2007
                            >A 90 deg vee twin has zero primary vibe at 50% BF, why
                            >would you want anything else ?

                            Thanks Ian - I guess a better way to ask that question would have been
                            whether or not there's any reason to think of a balance factor other than
                            50%. I have heard tuners that seem to know their stuff talking about
                            balancing over 50% of recip by several percent.

                            >>fixture or a nice fabricated low friction balance rig?

                            >No reason, you can get them pretty close with a bit a
                            >practice.

                            Thanks again - much appreciated. Didn't think I was missing anything, but
                            the more I learn the less I think I know, so it's nice to have confirmation.

                            Cheers -

                            Michael

                            --
                            No virus found in this outgoing message.
                            Checked by AVG Free Edition.
                            Version: 7.5.441 / Virus Database: 268.17.37/682 - Release Date: 2/12/2007
                            1:23 PM
                          • Ian
                            ... OK, I thought you were talking about changing it to 35% or 65% BF. Yes, I have heard this 48% to 52% BF argument for Ducati s but I have never ridden one
                            Message 13 of 24 , Feb 12, 2007
                              >I have heard tuners that seem to know their stuff talking about
                              >balancing over 50% of recip by several percent.


                              OK, I thought you were talking about changing it to 35% or
                              65% BF.

                              Yes, I have heard this 48% to 52% BF argument for Ducati's
                              but I have never ridden one set up like this so I can't comment.
                              All I can say is that physics says 50% BF gives you zero
                              primary vibe in a 90 deg V twin.

                              The secondary vibe can't be altered by changing the BF, but
                              it is partially cancelled anyway, and not usually too annoying
                              on a 90 deg V twin.

                              What is possibly going on is that introducing a small amount
                              of primary vibe counteracts some of the secondary vibe ?



                              Cheers IAN


                              See www.drysdalev8.com for :
                              - Drysdale 750-V8 Sports & 1000-V8 Cruiser
                              - DRYVTECH 2x2x2 Experimental
                              - Carberry Enfield 1000cc V-Twin
                              - Drysdale Hillclimb Open Wheeler


                              --
                              No virus found in this outgoing message.
                              Checked by AVG Free Edition.
                              Version: 7.5.441 / Virus Database: 268.17.36/681 - Release Date: 2/11/2007 6:50 PM
                            • Michael Bateman
                              ... Interesting thought. Perhaps that s it. For myself I m more interested in engine life rather than perception at this point. Race SV-650s have a terrible
                              Message 14 of 24 , Feb 12, 2007
                                >Yes, I have heard this 48% to 52% BF argument for Ducati's
                                >but I have never ridden one set up like this so I can't comment.
                                >All I can say is that physics says 50% BF gives you zero
                                >primary vibe in a 90 deg V twin.

                                >The secondary vibe can't be altered by changing the BF, but
                                >it is partially cancelled anyway, and not usually too annoying
                                >on a 90 deg V twin.

                                >What is possibly going on is that introducing a small amount
                                >of primary vibe counteracts some of the secondary vibe ?

                                Interesting thought. Perhaps that's it. For myself I'm more interested in
                                engine life rather than perception at this point. Race SV-650s have a
                                terrible reputation for broken cranks and I'm hoping to put a dent in it.
                                I've got several guys here that I've been building (sort of building - to a
                                real tight budget) race motors for that always seem to not be able to afford
                                time or money to do things right the first time, but just gotta have that
                                broken motor back together for the next race weekend. And it's gotta make
                                boatloads of power too of course.

                                This season I'm insisting on carefully balanced cranks and flywheels at a
                                minimum, and I want to make sure that I insist on the right thing
                                balance-factor wise. Some of the v-8 tuners say that the cranks need to be
                                overbalanced for high revs, and I've talked to a couple of Ducati tuners who
                                seemed to be thinking along the same lines.

                                It seems to me though that at least for 90 and 180 degree motors it
                                shouldn't depend on revs, unless something is incorrect in the balancing -
                                IE you didn't achieve 50% through an error in measurement or something like
                                that. But that's only how it seems to me - I've certainly not got enough
                                experience to know.

                                Cheers -

                                Michael

                                --
                                No virus found in this outgoing message.
                                Checked by AVG Free Edition.
                                Version: 7.5.441 / Virus Database: 268.17.37/682 - Release Date: 2/12/2007
                                1:23 PM
                              • Brent Prindle
                                ... From: Michael Bateman ... The major breaking point on the SV crank is between the main bearing and the rotor. Every one I have
                                Message 15 of 24 , Feb 12, 2007
                                  ----- Original Message -----
                                  From: "Michael Bateman" <michael.bateman@...>
                                  ...
                                  > Interesting thought. Perhaps that's it. For myself I'm more
                                  > interested in
                                  > engine life rather than perception at this point. Race SV-650s have a
                                  > terrible reputation for broken cranks and I'm hoping to put a dent in
                                  > it.
                                  > I've got several guys here that I've been building (sort of building -
                                  > to a
                                  > real tight budget) race motors for that always seem to not be able to
                                  > afford
                                  > time or money to do things right the first time, but just gotta have
                                  > that
                                  > broken motor back together for the next race weekend. And it's gotta
                                  > make
                                  > boatloads of power too of course.
                                  >
                                  > This season I'm insisting on carefully balanced cranks and flywheels
                                  > at a
                                  > minimum, and I want to make sure that I insist on the right thing
                                  > balance-factor wise. Some of the v-8 tuners say that the cranks need
                                  > to be
                                  > overbalanced for high revs, and I've talked to a couple of Ducati
                                  > tuners who
                                  > seemed to be thinking along the same lines.

                                  The major breaking point on the SV crank is between the main bearing and
                                  the rotor. Every one I have seen has been a torsional break in this
                                  area. Sometimes from the oil hole and sometimes from the keyway. Both
                                  good stress risers at the wrong place.

                                  Lightening up the rotor/flywheel, and keeping a high ratio between web
                                  and rotor mass seems to help. The crank inertial "absorbs" some of the
                                  shocks from the power pulses and there is less twisting of the crank
                                  behind the rotor. I think some of the overbalance is actually adding
                                  weight to the crank and helping the ratio.

                                  Talk to Lanigan (local guy) and he seems to swear by sending the cranks
                                  to Falicon for balance, true, and polish. He says that he has not seen
                                  a crank fail that has had this treatment. Perhaps there are some
                                  grinding issues from Suzuki that are being polished out, eliminating the
                                  stress risers from aggressive/coarse grinding.


                                  -oo
                                  Brent Prindle
                                  BrentP@...
                                • john fisher
                                  Zoran would know too, especially if you are in the Bay area. He s on here or the chassis list or both.
                                  Message 16 of 24 , Feb 12, 2007
                                    Zoran would know too, especially if you are in the Bay area.
                                    He's on here or the chassis list or both.

                                    .... Race SV-650s have a
                                    > terrible reputation for broken cranks and I'm hoping to put a dent in it.
                                    ... ...
                                    >
                                    > Cheers -
                                    >
                                    > Michael
                                    >
                                  • Ian
                                    ... But most V8 s have no balance webs on the centre throws at all, which they compensate for by twisting the webs on the end throws by 13 deg. or so. This
                                    Message 17 of 24 , Feb 12, 2007
                                      >Some of the v-8 tuners say that the cranks need to be
                                      >overbalanced for high revs,



                                      But most V8's have no balance webs on the centre throws
                                      at all, which they compensate for by twisting the webs on
                                      the end throws by 13 deg. or so.

                                      This means that the middle throws have ( effectively ) a BF
                                      of negative 200-300%. It creates massive stresses in the
                                      crank and main bearings, but cast iron blocks seem to
                                      stand up to it OK.

                                      You will see ongoing arguments as to the need ( or lack of )
                                      to fully counterweight V8 racing cranks. I'd be VERY
                                      nervous about running big revs in a alloy block V8 with an
                                      "end weighed" crank.



                                      Cheers IAN


                                      See www.drysdalev8.com for :
                                      - Drysdale 750-V8 Sports & 1000-V8 Cruiser
                                      - DRYVTECH 2x2x2 Experimental
                                      - Carberry Enfield 1000cc V-Twin
                                      - Drysdale Hillclimb Open Wheeler


                                      --
                                      No virus found in this outgoing message.
                                      Checked by AVG Free Edition.
                                      Version: 7.5.441 / Virus Database: 268.17.36/681 - Release Date: 2/11/2007 6:50 PM
                                    • Michael Bateman
                                      ... Hi Brent! Good to hear from you. Yes - two of the four breakages were the end of the crank breaking off. Both appeared to start at the end of the keyway.
                                      Message 18 of 24 , Feb 12, 2007
                                        > The major breaking point on the SV crank is between the main bearing and
                                        > the rotor. Every one I have seen has been a torsional break in this
                                        > area. Sometimes from the oil hole and sometimes from the keyway. Both
                                        > good stress risers at the wrong place.

                                        Hi Brent! Good to hear from you.

                                        Yes - two of the four breakages were the end of the crank breaking off.
                                        Both appeared to start at the end of the keyway. I'll be balancing all of
                                        the flywheels, and lightening the total-loss flywheels as much as possible
                                        before balancing. I'm thinking I'll also try to reduce the stress riser at
                                        the end of the keyway by careful grinding to remove the sharp corners.
                                        Interestingly enough Dan Zlock pointed out to me that the later model cranks
                                        have the keyway moved entirely under the flywheel taper, where earlier ones
                                        were only partially under the taper. I've also noticed that the end of the
                                        flywheel bolt corresponds almost exactly with the end of the keyway. I'm
                                        thinking that a slightly shorter bolt may also be in order.

                                        > Talk to Lanigan (local guy) and he seems to swear by sending the cranks
                                        > to Falicon for balance, true, and polish. He says that he has not seen
                                        > a crank fail that has had this treatment. Perhaps there are some
                                        > grinding issues from Suzuki that are being polished out, eliminating the
                                        > stress risers from aggressive/coarse grinding.

                                        I tried to get these guys to send the cranks to Falicon last year. Of
                                        course there "wasn't enough time" and they didn't want to spend the extra
                                        dough. I talked to Falicon quite a bit and they said that they polish and
                                        balance, and also recommend cryo treatment as well, and still find that the
                                        cranks may not last the season (but are much improved). I see now that they
                                        are offering a billet crank for the SV. Same with balancing the flywheels -
                                        no time or money.

                                        Two of the cranks however were broken at the crankpin on the inside of the
                                        flywheel side web. Right at the radius. Also, in almost all of the motors
                                        the flywheel side main bearing is walking around - the lower half is walking
                                        toward the crank. On the early motors it is retained by a plate, but on the
                                        later motor they (Suzuki) left that plate out and the main bearing just
                                        walks right out into the crank. Even on the early ones the bearing walks
                                        enough to bend the plate out almost a full mm toward the crank.

                                        In talking to Dan Z it appears that almost all of the high hp SV's do this -
                                        but I suspect that it's much worse in the ones with inadequately balanced
                                        cranks. Especially since two of the cranks broke at the web - looks like
                                        the crank is flexing a lot - probably really exaggerated by imbalance. I
                                        pinned one in place with a roll pin in the oil groove, and it appears to be
                                        staying in place, but that's a band-aid.

                                        I'm also guessing that these guys don't exactly operate the bikes with the
                                        most mechanical sympathy. I wouldn't be surprised to find they'd been
                                        bouncing off the rev limiter all the way around the track, and mechanically
                                        forcing it past the rev limiter on downshifts. Perhaps a slipper clutch is
                                        in order... :-)

                                        Cheers -


                                        Michael

                                        --
                                        No virus found in this outgoing message.
                                        Checked by AVG Free Edition.
                                        Version: 7.5.441 / Virus Database: 268.17.37/682 - Release Date: 2/12/2007
                                        1:23 PM
                                      • Gentry's Garage
                                        HiYa Guyz, I am glad this subject has come up again, as I am wrestling with the planing stages of an 76 degree BSA A10 motor, is there a mathmatical formula to
                                        Message 19 of 24 , Feb 13, 2007
                                          HiYa Guyz,
                                            I am glad this subject has come up again, as I am wrestling with the planing stages of an 76 degree BSA A10 motor, is there a mathmatical formula to get to a starting point for the balance factor. I have been looking for a while and haven't come up with anything except this are that balance factor works for me.
                                          Thanks
                                          Thad
                                           


                                           
                                          Check out the Project Travelall happening at Gentry's Garage!!!!!!!!!!!!!
                                        • John Mead
                                          Have it dynamically balanced. John Mead
                                          Message 20 of 24 , Feb 13, 2007
                                            Have it dynamically balanced.
                                            John Mead
                                            --- Gentry's Garage <gentrysgarage@...> wrote:

                                            > HiYa Guyz,
                                            > I am glad this subject has come up again, as I am
                                            > wrestling with the planing stages of an 76 degree BSA A10
                                            > motor, is there a mathmatical formula to get to a starting
                                            > point for the balance factor. I have been looking for a while
                                            > and haven't come up with anything except this are that balance
                                            > factor works for me.
                                            > Thanks
                                            > Thad
                                            >
                                            >
                                            >
                                            >
                                            > Check out the Project Travelall happening at Gentry's
                                            > Garage!!!!!!!!!!!!!
                                            >
                                            > http://www.pirate4x4.com/forum/showthread.php?t=455088
                                            >
                                            >
                                            >
                                            >
                                            >
                                            >
                                            >
                                          • Ian
                                            ... You still need the BF to make the dummy weights. Only bike cranks you can dynamically balance without dummy wts & knowing the BF, are 4 cyl cranks. ( OK -
                                            Message 21 of 24 , Feb 13, 2007
                                              >Have it dynamically balanced.


                                              You still need the BF to make the dummy weights.

                                              Only bike cranks you can dynamically balance without dummy
                                              wts & knowing the BF, are 4 cyl cranks. ( OK - CBX1000
                                              cranks as well I suppose )



                                              Cheers IAN



                                              > > I am glad this subject has come up again, as I am
                                              > > wrestling with the planing stages of an 76 degree BSA A10
                                              > > motor, is there a mathmatical formula to get to a starting
                                              > > point for the balance factor. I have been looking for a while
                                              > > and haven't come up with anything except this are that balance
                                              > > factor works for me.

                                              See www.drysdalev8.com for :
                                              - Drysdale 750-V8 Sports & 1000-V8 Cruiser
                                              - DRYVTECH 2x2x2 Experimental
                                              - Carberry Enfield 1000cc V-Twin
                                              - Drysdale Hillclimb Open Wheeler


                                              --
                                              No virus found in this outgoing message.
                                              Checked by AVG Free Edition.
                                              Version: 7.5.441 / Virus Database: 268.17.37/682 - Release Date: 2/12/2007 1:23 PM
                                            • John Mead
                                              The shop doing the dynamic balancing has the dummy weights and use them as needed. I just supply the crank,rods,bearings,pistons,rings,clips etc. and they do
                                              Message 22 of 24 , Feb 14, 2007
                                                The shop doing the dynamic balancing has the dummy weights and
                                                use them as needed. I just supply the
                                                crank,rods,bearings,pistons,rings,clips etc. and they do the
                                                job.
                                                John Mead
                                                --- Ian <iwd@...> wrote:

                                                >
                                                > >Have it dynamically balanced.
                                                >
                                                >
                                                > You still need the BF to make the dummy weights.
                                                >
                                                > Only bike cranks you can dynamically balance without dummy
                                                > wts & knowing the BF, are 4 cyl cranks. ( OK - CBX1000
                                                > cranks as well I suppose )
                                                >
                                                >
                                                >
                                                > Cheers IAN
                                                >
                                                >
                                                >
                                                > > > I am glad this subject has come up again, as I am
                                                > > > wrestling with the planing stages of an 76 degree BSA A10
                                                > > > motor, is there a mathmatical formula to get to a starting
                                                > > > point for the balance factor. I have been looking for a
                                                > while
                                                > > > and haven't come up with anything except this are that
                                                > balance
                                                > > > factor works for me.
                                                >
                                                > See www.drysdalev8.com for :
                                                > - Drysdale 750-V8 Sports & 1000-V8 Cruiser
                                                > - DRYVTECH 2x2x2 Experimental
                                                > - Carberry Enfield 1000cc V-Twin
                                                > - Drysdale Hillclimb Open Wheeler
                                                >
                                                >
                                                > --
                                                > No virus found in this outgoing message.
                                                > Checked by AVG Free Edition.
                                                > Version: 7.5.441 / Virus Database: 268.17.37/682 - Release
                                                > Date: 2/12/2007 1:23 PM
                                                >
                                                >
                                                >
                                                >
                                                >
                                                >
                                                > Yahoo! Groups Links
                                                >
                                                >
                                                >
                                                >
                                              Your message has been successfully submitted and would be delivered to recipients shortly.