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My 101 Scout Cannonball Build

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  • My 101 Scout Cannonball Build

    Good news, I got picked to run in the 2020 cannonball on my 29 Scout 101! Bad news, I've got to get my pile of parts ready to drive across the USA in 76 weekends. I've restored a few cars but this is my first motorcycle, my first flat-head, and my first air cooled 2 cylinder so I might need some help. I'm trying to do as much of the work myself, building the bike instead of just bolting parts together.

    So right away I have a question, All of the bushings on the bike are long since shot and I'm stuck trying to push out the cam intermediate gear blind bushings. Is there a secret to getting these bushings out?

    Thanks for any help,
    Attached Files

  • #2
    Congratulations on getting into the Cannonball, its a hoot! Better start spending now....

    I just completed a timing gear rebuild on my 24 Big Chief, post Cannonball 2018. It was always noisy and by the end of the cannonball, it was much worse!

    Three ways to get the bushing out: Plug the small oil hole, tightly, then fill the hole with heavy grease and use a steel shaft that fits the hole as snug as possible without binding. Drive it in briskly, sometimes the hydraulic pressure will push the bushing out. May also need to plug the oil slot.

    Second way is to use a bushing puller made for blind holes. Here is one on ebay:

    I had to do some modification to get mine to fit as there is very little room behind the bushing to grab onto.

    Third way is to tap the hole and use a bolt and socket or such to pull it out.

    I also made new shafts for the idler gears as the originals were worn very badly, some of the bushings had over .014" clearance between the worn shaft and bushing. The shaft should be .623" and using a .625" reamer, that gives .002" clearance. I carefully fitted each bushing then assembled the gear train with no cam followers. There was some slight drag in places so I put 500 grit lapping compound in all the holes and turned the entire train using the oil pump drive worm and lapped in the bushings. It now turns easily all the way through.

    Good luck!


    • #3
      >> Congratulations on getting into the Cannonball, its a hoot! Better start spending now....

      Thanks, The spending has already started and I've been practicing by burning $100.00 bills every morning.

      I tried the hydraulic way this weekend and like an idiot completely forgot about the oil hole and got an eye full of grease with the first hit. I might try filling the bushing groove and hole with epoxy and try it again this coming weekend.

      And, thanks for the oil pump trick to test the gears binding, that's a good idea.



      • #4
        Well the hydraulic thing worked, I got all three blind bushing out in less then 10 minutes!

        I sealed up the oil hole and groove with just a tiny bit of epoxy and let it cook in the oven at 225 for awhile. Then filled the bushing with grease and gave it a good 'tap', not a whack. It was pretty damn cool, the thing just popped right out. One quick safety tip, I turned down a piece of junk steel rod to fit the bushing but I only did about an inch and the bushing gets stuck on it about half way out. You'll need a good two inches to get it cleanly with one quick tap.
        Attached Files


        • #5
          Dana -

          As the Moderator of AMCA Forum I like to promote the heck out of member bike builds and I am glad you have already start your build thread for the 2020 Cannonball. If I can do anything from the forum perspective please give me a holler. s we have seen in other Cannonball build threads people follow right up through to the end of the race. I always learn a great deal especially about problem solving and the big one - logistics. Goodluck.

          Mike Love


          • #6
            >> Mike
            Thanks, I too learned a lot from the previous threads and have read them frontwards and backwards. I'll try to get pic's up as often as I can.

            So I got almost all of the engine and transmission apart, all the gears look good, none of the bushings are even close to spec and all of the bearings and races have some or a lot of rust pitting. I can replace all of the bearings in the engine and transmission pretty easily but I'm worried about the drive race and pinion race. They both have some pitting, but not horrible.

            So my question is will I be able to replace these races without making things worse. Are there any 'got-yous' I should know before I replace the drive or pinion races in the crankcase? Also the trust washer under the pinion race is lose. Is that normal? Is it just the pinion shaft that keeps it lined up?

            Thanks for any help.


            • #7
              Best of luck with this!
              W/r/t pitting in bushing ID: IMHO (just me!) unless the pitting is wide enough to actually make a leakage path to either end (viz., are the pits connected?), the rotating journal will still develop oil pressure by the hydrodynamic wedge effect. I would leave the bushing alone unless this can be done devoid of any error (too loose, too tight, misaligned). I have seen cases and inserts cracked by inserting a "new" bushing that was a RCH too large.
              I haven't worked on a 101 for 40 years, so much of this is generic to flatheads for me.
              I would be conservative on valve seat width, .125" rather than .060" especially for the exhaust - wide will run the valve head cooler and eat more dirt without losing seal (even though it will flow slightly less).
              The exhaust valve must present to the chamber instantly it cracks open: with the valve open .001" there should be a clear path from the seat to the open chamber without any masking/shrouding. Check with a flashlight. Easy to do, just blend the upper head gasket surface into the seat OD (final highest angle cut) all around (but the 180 degrees facing the bore most important). This greatly affects seat and cylinder temperature.
              A bronze guide insert will run dry without damage vs. an iron guide.
              If you have the room, a lash cap will save the valve stem tip from pounding a dent in the tappet.
              I have a gut feeling that a squirt of something (aerosol?) inside the valve cover on occasion will keep the spring cooler and extend stem life, but haven't tried it. Even a small hole will push out oil vapor when the engine is hot, so if you make a hole figure out how to cover it when you don't need it.
              I know very little about the breather disc except that continuous high speed use needs slightly different than traffic?
              I would cover as much of the drive chain as possible top & bottom, but leave a hole to spray it daily (rotate the wheel to get the whole chain).
              They used to drill holes in the skirt half-way down the skirt for oil to reach the wall but stay small (1/4"?) and radius the hole inside & out. Not close to skirt bottom, or directly on the thrust line! I've seen skirts cut with a hacksaw in a shallow "X" across the thrust for oil retention, but results?
              Paint: sandblast cylinders and heads, lightest possible coat of flat black for lowest temperature.
              Crude trick for 1/4 added hp: remove some teeth from rear sprocket; 48 remove 12, 16, or 24, 1/3 if divisible by 3, etc. On some counts the math doesn't work, should keep the sprocket balanced.

              The Linkert Book


              • #8
                74 WTR (Weekends To Race)!

                I got the bronze stock I needed to make the bushings last week and finally had time to make some this weekend.

                You read the Internet and listen to the old timers and you get the feeling you can just whip these out in a few minutes. Well not for me. It's measure, measure again, math and cut. Then measure, measure again, math, measure, more math, measure then cut. And measure, crap forgot to divide by two. Start over again.

                Lessons learned:
                Don't do the math in your head!
                Don't forget to divide by two when turning down.
                Don't put the bushing back in the lathes' jaw after you've turned down the ID and OD. You'll squeeze it out of shape.
                Get a chair and sit, I think better sitting down.

                Any way I got the transmission main shaft bushings all done and pushed into the clutch basket and drive gear. I honed the sprocket side bushing to 0.0015 and the clutch side to 0.001. They both fit nicely.


                I'm half way done with the cam case bushings. I'm hoping I can finish these this week, because I'll be gone the next few weekends for vacation and work.

                Just a quick pic of my 1932 South Bend lathe and the transmission all ready to be put back together.



                • #9
                  Originally posted by d_lasher View Post
                  Don't forget to divide by two when turning down.
                  You need a direct reading dial on your lathe. Not only are the divisions further apart, if you want to reduce the diameter by 0.003" you dial in 0.003", not 0.0015". Or should that be 0.006"?...

                  I'm sure my lathe's direct dial has saved me countless times.


                  • #10
                    It’s been awhile, I was on vacation for a little bit, and then had to travel for work. I realized this weekend I never took the time to upload pics of my project. I’m calling him Oscar, Oscar the bastard. Here’s his picture when I first got him home.


                    And my current progress,


                    I changed his name to Oscar the bastard because everything on the bike was wrong, missing, or broken. Just as an example, a few magneto parts came up for sale on eBay this last week so I decided to crack open Oscar’s and see if I needed them. Here’s a picture of Oscars magneto with the cover off,


                    See anything missing, like a magnet or a winding? I guess I’ll add them to my show stoppers list.

                    More later...


                    • #11
                      69 WTR

                      This was a good weekend. I got the cam bushings and gears all setup and ready to go. I used gharper's advice on the lapping compound and using the oil drive gear to drive the gear train, but it was hell on my hands so I changed it up a bit. I put a bolt through the magneto gear and drove the gear chain with a wrench.


                      Then I decided to deal with the pinion and drive shaft races. The pinion race was not only heavily pitted but it was also not all the way into the housing and the thrust washer behind it was loose. So I decided to go against kitabel's advice and replace it. So I put the crankcase in the oven at 275 for an hour. When I pulled the case out and put it on the ground to push the race out, it just fell out. I was a little worried about getting the new one back in inline with the drive race. So I decided to make a tool to push the pinion race in through the drive race.


                      It worked like a charm. It's always a good sign when you spend an hour making a tool you only use for a minute. Put the case into the oven and the push tool with the race on it into the refrigerator for an hour. Assembled the case and pushed the pinion race in with the pushing tool through the drive race. Just like that it was in and straight.

                      For the drive race I decided against pushing it out. The first rule of the workshop is 'Don't make it worse'. I was worried I'd make a mess of things trying to push a new one in. So, instead I honed out the race 0.0015 inches, I'll make up for it with over-sized roller bearings. That took most of the pitting out. What remains should be OK. As kitabel suggested the pitting isn't connected and the oil layer should keep the bearings protected.

                      Now it's on to the flywheels.


                      • #12
                        The flywheel work didn't pan out. In order to balance the flywheels I need to assemble the connecting rods and one piston. But the big end bore was 0.005 over the OD of the brand new races I have. I guess I'm supposed to hone out the big end of the connecting rods to fit. I'm thinking I need to bore them out to an interference fit of 0.0015-0.0020, unless someone knows better.

                        Either way I have to wait because I don't have the right size hone stones to fit. So I'll have to order them and wait.

                        I decided to leave the land of thousands and move back to the land of close enough. I went back to my rear hub. I last worked on the rear hub back when I was just going to ride around town on the bike, not drive it across the country. I have a 28' scout rear hub with the ball bearings instead of the roller bearings. And all of the races we're iffy.

                        So I decided to get the bearing races out of the rear hub. Here's how not to do that. 1) Use a big hammer and a drift through the axial at an angle. Result: Nothing happens. 2) Use a 20 ton press with the drift catching the lip of the race to push out. Result: Heat treated race shatters into a million pieces. 3) Use a dremal to cut it out. Result: Would have ruined the hub case. 4) Go to harbor freight and buy a 'Rear Axle Bearing Puller Set'. Result: Get home and find out it's too big. 4) Give up and call it a day. Result: Frustration.

                        Wake up the next day and sit and think for all of 5 minutes. 5) Cut a 2 inch piece of 1/8 inch piece of flat steel bar. Drop it down the axial flat on the back of the bearing. Push it out with the press. Took about 15 minutes all together and both races came out with out any drama at all.

                        I think T. Cotten said in another post some where, only the Harley guys use hammers. I should have listened.


                        WTR : 68
                        Last edited by d_lasher; 05-28-2019, 02:28 PM.


                        • #13
                          It's been awhile. Last weekend we got a chance to go hunting for parts at the 'Dirty Dog Roadhouse' swap meet in Golden CO. It was pretty small and we didn't find any of the parts we were looking for. But, right away we caught a glimpse of a early Indian Chief with a cannonball number on it! We went right to it and started talking with owner. Turns out it's gharper from here. What a small world. Even though we didn't find any parts we needed, we got a ton of information, tips and advise. We talked, actually I asked questions and he answered them, for at least an hour. We even got a ride in his side-car! What a nice guy.

                          This last weekend it was back to work. All I managed to do this weekend was assemble the connecting rods and bearings and test fit everything. First, I had to hone out the rod's big ends so I could push the race in. Then I built a tool to push the races in. I swear I spend more time making tools then using them. I spent all day Saturday and most of Sunday making the push tool. It had four parts, a base for the rod to sit on. A sleeve that fit in the rod and held the race to keep it square. A collar to push against the race and fit inside the female end of the rod. And a push rod to keep every thing square and together.


                          You can even just make out the 0.030" grove in the collar to have the race stick out 0.030" of the male connecting rod. l'll put drawings up on my blog, soon.

                          After I got the race's pushed in I had to hone the races to fit the bearings. The whole process takes me forever. It's the measuring that takes so long. I'm so worried about overshooting the diameter, I have to measure it ten times every 5 minutes. Hone, both ways, clean it up, take it to the workbench and measure it 10 times frontwards and backwards and then repeat the process again and again. All to take 0.002 inchs out. I could never do this for a living, I'd go broke.

                          I did manage to mock up the flywheel yesterday. Today I'll start balancing them.

                          WTR : 66


                          • #14
                            Congratulations on the progress and accumulated wisdom.
                            On the balancing: many motors removed from service will show holes drilled into the outer faces of the flywheels, since this is all that's available when they're assembled.
                            However, any weight removal should be in the inner faces only. Not really practical, this includes filling in any outward-facing holes and starting over.
                            Weight removed from the outer faces places the actual center of gravity on a line between the crankpin and the balance holes, which will be a diagonal rather than a vertical line. As the flywheel spins up, the mass of each side tries to rotate around its center of gravity rather than its shaft center, and this imbalance produces vibration, and flexes each crankpin and shaft taper in its hole by bending.
                            The Linkert Book


                            • #15
                              Thanks, that was one of my questions and it does make sense. I do have more questions about balancing. I feel like the old trick of balancing the flywheel with both rods and one piston isn't right when my pistons are aluminum and weigh a lot less now then the old factory pistons. So I'm thinking, and I almost hate to bring it up, of weighing everything and just using a balance factor of 68%. I searched online and somewhere, someone said 101 scouts had a factory balance of 68%.

                              My thoughts are I'm looking for a slow, reliable ride and the higher factor would give a better general purpose ride. The last thing I want is a drag racer. Does this make sense? If I use these numbers I end up using the two rods, one piston and an extra 30 grams.

                              Fine print, by piston I do mean piston, rings, clips and pin.

                              When I hang this up on the balance beam I'm off by a lot. I figure I'd have to drill 7 to 8 holes? Does that seem right?