Vintage J-Model Whizzer

Discussion in 'Whizzer Motorized Bicycles' started by Paula, May 22, 2011.

  1. Paula

    Paula Member

    Hi folks,

    As I mentioned in my intro post, I recently purchased a vintage Whizzer. It came from a gentleman in Pennsylvania (I'm in Indiana), so there was a longish drive involved in picking it up. Here are some pictures I snapped just after the seller brought it up from his cellar:



    He was a bit surprised when I showed up to pick up the bike in my compact sedan, as he didn't think there was any way we'd get the thing in there. He didn't realize that my rear seat folds down, and I knew that as long as we could get the handlebars off, it would be no problem. I was right -- it took less than five minutes to remove the handlebars and get the Whizzer stowed for the trip home. Here are some pictures I took back at the hotel:



    The trip home was uneventful. My next door neighbor helped me unload the bike. He's retired and in his seventies, and was tickled to see it. He says he remembers them being very popular right after the war, as automobiles were still rather scarce.

    Anyway, I'm now in the process of going over the bike, checking things out, taking pictures, and making notes of things will need to be replaced. The engine s/n is J-204166. Tires are shot, no belt guard or chain guard. The previous owner says he drained the gas from the tank after the last running. I confirmed it -- the inside of the tank is dry and clean. The frame is typical Schwinn, and has the indents for belt clearance.

    I've done a lot of reading of previous threads on this forum, which has been most helpful. I'm hoping the you folks may be able offer advice and suggestions as I get further into this project.


  2. itchybird

    itchybird New Member

    Nice looking ride Paula, you'll have a lot of fun with that one, thats for sure! And just in time for summer too, well done.

  3. rustycase

    rustycase New Member

    What a GREAT bike, Paula!
    Hope you have loads of fun with it this summer!
  4. Paula

    Paula Member

    Thanks for the nice comments! :grin5:

    I don't know about this summer, though. From what I've seen so far, this bike will need A LOT of work. Still, it'll be fun watching it slowly take shape!

  5. swaney3

    swaney3 New Member

    Great Looking Ride... I can't wait to learn more about it as you get it up and running the seat looks very comfortable.
  6. Paula

    Paula Member

    Thanks, Swaney. Though not as comfortable as it surely once was, as the previous owner said, the seat "still has life left in it." It's a vintage Mesinger leather saddle (the brand imprint is just barely visible in the right light):



    I would really love to have it restored by an expert, but I understand the cost can be several hundred dollars. Something I may have to save up for.

    Last edited: May 24, 2011
  7. Paula

    Paula Member


    Sure seems difficult to make progress this time of year, with all the yard work and outdoor activities! Plus things are really busy right now at work (big change from a year ago!) Nevertheless, have been making some headway.

    I'm realizing that this bike has had a very active life. The expression, "Rode hard and put away wet" seems appropriate. Poor maintenance, ham-fisted repair attempts, and jury-rigging are all in evidence. Which is not to say I'm either surprised or disappointed. I was looking for a project, and got the bike for a very reasonable price. It will serve as a platform for a fun and rewarding restoration. I actually enjoy bringing things back from a state of abuse and neglect.

    Some of the problems I've noticed so far:

    1) The bike came without a belt guard, and I found a possible reason why. At some point, the clutch pulley managed to crash into the magneto guard, causing substantial damage to the belt guard mounting posts. The same mishap may also be responsible for the apparent damage caused to the rim of the flywheel when the magneto was pushed into contact with it (see arrows in picture below):


    I've purchased a replacement magneto guard, though it's a repro and looks like a sand casting rather than the original die casting. Should work fine though, even if not quite as robust as an original one.

    2) Not long after receiving the bike, I noticed that several of the cylinder head bolts were visibly loose. (Huh?) I removed all the bolts and examined the head. A couple of fins were broken off, but the most distressing thing was the condition of the bolt bosses. They were smashed down nearly to the point of obliteration, the holes egg-shaped, and the whole head had kind of a distorted appearance. I'm not sure exactly what caused the damage, but it looks like a combination of severe overheating, and extremely over-torqued bolts. Here are some pictures of the head that came with the bike, alongside a nice used one that I bought on eBay:



    An additional problem with the head is that the spark plug hole has been enlarged and tapped out to accommodate a larger plug, probably due to stripped threads.

    Having dismantled and examined most of the engine by now, the condition of the cylinder head doesn't jibe with the condition of the rest of the engine, which is not too bad. I wonder if the original head got swapped out sometime after the owner quit riding, possibly for service on another engine. This would tend to explain the loose bolts.

    Stay tuned for more...
    Last edited by a moderator: Dec 15, 2015
  8. Mike Notigan

    Mike Notigan Member

    Can't wait for your next installment! It seems you have a good gameplan for the restoration of your bike. And I see the potential your bike has. Good luck on the restoration!
  9. Paula

    Paula Member

    Thanks for the vote of confidence, Mike!

    I've got the engine fully disassembled now, and all the parts that will be re-used have been cleaned and inspected. The crankcase is in pretty good shape, with only a few minor issues. One of these concerns the tapped holes for the engine mount brackets. These three 5/16-18 holes are tapped directly into the cast aluminum, and two of them show significant damage. No doubt they take quite a beating from engine vibrations, road shocks, etc.

    A well-known and accepted method of repair is to install a HeliCoil thread insert. Fortunately, the company where I work has HeliCoil kits for numerous thread sizes, and a shop foreman who is happy to let me borrow them. I usually buy a package of thread inserts, and donate any leftovers to the shop.

    The first step is to drill out the damaged threads with the appropriate size drill bit. This picture shows the crankcase mounted in a drill press, ready for drilling:


    The size of the bit is specific to the special HeliCoil tap that will be used to accommodate the insert being used. The inserts I am using are 18-8 stainless steel, 15/32" long. Here is the drilling operation:


    The HeliCoil tap has the same pitch as the thread being repaired, but a larger pitch diameter. Make sure that the hole has been drilled deep enough so that the tapered end of the tap does not bottom out before sufficient full-depth threads have been formed:


    After tapping the hole, the insert is threaded onto an installation tool. A "tang" at the bottom of the insert keeps it from threading any further onto the tool. The insert is threaded into the tapped hole until it is just slightly below the surface:


    Once the insert has been threaded into the hole to the correct depth, the installation tool can be unscrewed and removed. If you think that you might be installing bolts deeper than the length of the insert, the "tang" can be easily removed by inserting a close-fitting pin into the insert, and tapping lightly with a hammer. The tang breaks free and can be removed from the hole. Here is the finished repair:


    Next: Fixing a wallowed-out clutch arm pivot hole
    Last edited by a moderator: Dec 18, 2015
  10. Mike Notigan

    Mike Notigan Member

    Excellent work and great pictures! It looks like your Whizzer is going to get that second lease on life that it deserves.

    I hope the moderator reads this and considers Paulas' project as a sticky on how to restore a vintage Whizzer

    2008 Whizzer NER
  11. BoltsMissing

    BoltsMissing Active Member

  12. RdKryton

    RdKryton Active Member

    Your doing it right!

    This is a very detailed thread. I'm glad you made it a sticky Bolts.
    I will be watching for every installment. Great job so far.

  13. Paula

    Paula Member

    Thanks, I appreciate the sticky-status! Readers should keep in mind, though, that I don't pretend to be any kind of Whizzer expert (this is my first one) so I invite all to weigh in with suggestions or comments as I go along.

  14. Paula

    Paula Member

    After removing the engine from the bike I noticed that the clutch arm had quite a lot of "wobble" to it. Disassembly and clean-up revealed what I suspected: the pivot-pin hole in the crankcase is worn significantly oversize.


    I'm not sure how much of an effect this would have on clutching action, but I'm guessing that it is not a good thing. Interestingly, I've seen pictures of other Whizzer crankcases which show a bronze or Oilite bushing here. Also, my Owner's Manual shows some kind of bushing, part #2086 "Bushing - Trunnion" (Item 26 in the picture below):


    In the manual's usage column, it shows this bushing as applying to all models covered by the manual (H, J, 300, & 700). At any rate, my engine doesn't seem to have had one originally, though it certainly looks like it could use it.

    I purchased a bushing from an industrial supplier, measuring 1/2" inside diameter, 5/8" outside diameter, and 1-1/4" long. It is an Oilite bushing, meaning that it is made from a porous bronze material, impregnated with a self-releasing lubricant. The length is slightly longer than needed, so I had to cut one end down in the lathe.

    These bushings are made oversize. They are designed to be pressed into an on-size reamed hole, such that the inside diameter will be correct after assembly. The first step is to drill out the original hole in preparation for reaming. In this case I'm using a 19/32 drill (WD-40 makes a good cutting fluid for drilling and reaming aluminum alloys):


    This leaves 1/32" for reaming -- about the most you would want to remove by reaming, but my drill bit collection is rather sparse above 1/2", and we can get away with it in this case. The drilling operation was followed with a 5/8" on-size reamer:


    The reamed hole should be chamfered slightly to remove any burrs, and to give a bit of a lead-in for the bushing. Before pressing in the bushing, it's a good idea to apply a bit of oil inside the reamed hole. Not absolutely necessary with an oilite bushing, but still a good idea. I used a handy-sized socket as a bushing driver in combination with an arbor press to drive the bushing home:


    Here's the result:

  15. Quenton Guenther

    Quenton Guenther Motored Bikes Sponsor

    Hi Paula,

    Looks like you are restoring the motor as it should be.

    Sadly I didn't see this post earlier, as I could have supplied you with additional information. Whizzer sold a kit to repair the stripped 5/16" crankcase mounting studs, and was simply a step-stud with a 3/8" on one side and 5/16" on the other, of course it required drilling and tapping the crankcase holes, same as installing the heli-coils.

    The cut in the magneto cover was common and caused by the AX belt being too small from some companies [gates,etc]. In order to slacken the front belt the pulley hit the cover if the belt was too short.

    The wear on the O.D. of the flywheel was most often caused by a worn out main bearing that allowed the flywheel to "wobble", and both versions [Bendix & Hall] of the flywheel generators also cut a groove in the flywheel.

    The clutch bushing became standard on a few [very few] later "J" motors, and all later versions [300, 300S, 500, 600S, & 700].

    The most common reason for distorted head bolt holes was the missing THICK washers on the head bolts.

    You can and should replace both the crankshaft bearing and seal. Sadly the only part you won't be able to replace is the Torrington needle bearing in the side cover, but if you need one, I have some really good used ones. You should also consider replacing the clutch pulley bearing.

    I have lots of NOS Whizzer parts if needed, and can tell you where to find parts if I don't have them.

    Make sure the new head is flat, as they distorted easily. I normally work on a marble slab with #220 paper to make sure it is completely level.

    When you get to the ignition system, I would suggest replacing the points with the electronic module, as the points have always been problematic [I pushed my vintage Whizzer many miles as a youth over points problems].

    Have fun,
    Last edited: Jul 16, 2011
  16. Paula

    Paula Member

    Hi Quenton,

    Thanks for your comments and suggestions! It's reassuring to have such a wealth of experience available for a project like this.

    Interesting... this engine had the thick head bolt washers in place, which is one more reason to suspect that the original head was removed and swapped with this "spent" one.

    Excellent suggestion. I have a small surface plate in the shop that is idea for this sort of thing.

    Thanks again for your valued input!

    Last edited: Jul 18, 2011
  17. KilroyCD

    KilroyCD Active Member

    This is an excellent thread, Paula. Being a Whizzer enthusiast myself, I'm chomping at the bit for the next installment.
  18. Paula

    Paula Member

    Valve Grinding

    After disassembling the cylinder from the crankcase, I removed the intake and exhaust valves. The process is fairly simple -- I used a pair of needle-nose pliers. With the cylinder upside down on the bench, the open pliers can be inserted in the valve lifter holes like an inverted "V", compressing the outer rim of the valve spring washer, 180 degrees apart. With the valve spring thus compressed, it's a simple matter to remove the C-clip from the valve stem with a second pair of pliers. This releases the spring washer and spring, and the valve can be removed through the top of the cylinder.

    The condition of the valves is about what I expected: not great, but not too bad. The exhaust valve showed some pitting, but was not burned. The intake valve showed more wear, and rather uneven wear, though it was not pitted as much as the exhaust valve. After cleaning and a light wire brushing, this is how the valves looked (exhaust valve on left):


    Given that new Whizzer valves seem to be a rather scarce commodity, and expensive when they can be found, I decided to try regrinding the original valves. As a fun alternative to having the valves serviced at a commercial small engine shop, the job can be performed by the do-it-yourselfer fortunate enough to have a shop equipped with a small lathe, and a die grinder ("pencil grinder").

    The process consists of rotating the valve slowly in the lathe by its stem, while passing a small grinding stone across the valve's margin and face. The grinding stone is held in the collet of the die grinder, which is in turn mounted on the lathe's compound, carefully set to a 45 degree angle. I would advise against using the compound's degree scale to set the angle -- they cannot be relied upon for precision. I mounted a magnetic base indicator to the compound, and passed it along a 45 degree angle block held against a spindle-mounted faceplate. With the compound's locking screws only snugged up, the compound can be lightly tapped one way or the other until the indicator reads zero. Then tighten the locking screws.

    The valve stem needs to be mounted with a high degree of concentricity. In other words, we want the ground surfaces of the valve to be as concentric as possible with the stem. Some kind of collet setup is ideal. My lathe uses 3-C collets, and I have them at 1/32" increments, but the valve stems are an odd size (.230" dia.) So, I made a brass split bushing to adapt the stem size to an 11/32" collet:


    Making such a bushing is a simple operation, and the "split" can be made with a bandsaw (as I did) or a hacksaw. Here's what the valve looks like with the bushing in place:


    (A possible alternative to the collet system would be a 4-jaw chuck, but it would necessitate accurately centering the valve with an indicator.)

    The die grinder is mounted to the lathe compound by means of a boring-bar holder. Once again, a brass reducer bushing serves to adapt the grinder body's OD to the holder's ID. Don't tighten the boring-bar holder's clamp screw too tight -- the grinder body might be compressed to the point of locking up. Just tighten enough to hold the grinder securely against very light cuts, which is all this method is capable of making.

    A word of caution is appropriate here: The abrasive dust that this kind of operation produces can be VERY DETRIMENTAL to the precision bearing and sliding surfaces of a lathe. Therefore, take steps to shield the lathe from grit. Also, using a lathe in this fashion should be no more than an occasional thing, not a frequent occurrence, unless you are prepared to accept a shortened useful life of your machine tool.

    Here is the basic setup. (Note the plastic film and mounds of shop rags employed to keep grinding grit out of the lathe):


    The lathe is run in reverse (against the direction of the grinding stone) at a moderately slow speed. Very light passes are made across the face of the valve, until the surface "cleans up". Heavier passes can be taken at first, but as the surface becomes smoother, more surface is exposed to the grinder, and lighter cuts must be taken. Here's another view of the setup, showing how the grinder is mounted in the boring-bar holder:


    Once both valve faces have been ground, reset the compound angle to 90 degrees, and grind each valve's "margin" (the cylindrical portion at the valve's large diameter) until it cleans up at around 25-30 thousandths wide. Here's the finished valve grinding job:


    It should be noted (and obvious) that regrinding a valve reduces it's size. It's entirely possible that the dimensions of a reground valve may no longer fall within factory specs. This may result in the valve sealing too low in the valve seat -- not an optimal situation. I think these valves will be ok, but we will see how it looks once the seats have been re-cut.

    Last edited by a moderator: Dec 18, 2015
  19. RdKryton

    RdKryton Active Member

    Nicely done! Hope they are still in spec.
  20. jbcruisin

    jbcruisin Member

    What happened to the pictures?