Vintage J-Model Whizzer

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Clutch Arm

The clutch arm was broken when I purchased this bike. The casting had fractured where the clutch cable attaches to the end of the arm:

ARM01.jpg


A previous owner had jury-rigged the setup so it would work, but I still wanted to replace the arm for the purposes of this restoration. My first thought was to fabricate one from steel bar stock (since I enjoy that kind of work), but before I got around to it, an alternative presented itself. I was talking to Chuck Gatto, and he mentioned that he was making up some repro clutch arms for sale, and had had some castings made and machined. I happened to mention that I was considering fabricating a new clutch arm for my engine. Not long after, I received a package in the mail with an unmachined clutch arm casting, along with a note: "Hi Paula, This one is on me. Have fun!, Chuck."

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So, thanks to Chuck, I would be able to make a new clutch arm, just like an original! Here's a picture showing the original broken arm next to the new casting I was given:

ARM02.jpg


The machining of the clutch arm casting is fairly straightforward. With the casting mounted "pulley" side up, the hole for the pivot pin is drilled and reamed, the larger boss is faced, and the 1/2-13 hole for the pulley bolt is drilled and tapped:

ARM05.jpg


The casting is then inverted in the vise so that the pivot pin boss (where the arm rides against the crankcase) can be faced:

ARM06-1.jpg


Next, the arm is positioned with the top side up. A 17/64 hole is drilled to a depth of about 3/4". Then, a 9/64" hole is drilled through the arm:

ARM07-1.jpg


Lastly, a 1/16" wide slitting saw is used to slit through to the center of the drilled end of the arm. Also, a 1/4-20 hole is drilled and tapped for attaching the spring anchor:

ARM08.jpg


The pivot pin was made from a piece of 1/2" dia. drill rod. One end of the pin was tapped 5/16-18 for the retainer bolt. The finished pin was pressed into place. After smoothing up the casting a bit, a couple coats of primer were applied. Here's the finished arm after painting, ready for duty:

ARM11.jpg


Paula
 
All this Quality!! really makes a person appreciate whats available to us from guys like Joe Cargola,Fred White, Ron Houk, Fred Koeknke, Ralph Westman, others like your self. I really need to get busy and start one of my vintage bikes. I've been doing mods with my new edition whizzers, the clutch arm needs to be made right. maybe?

Can't wait to see the next phase of your project!

Ray
 
Exceptional work Paula. I feel bad for saying this but I am glad you stumbled across a bike that needed so much work. Keep the pics and details coming.
 
That is a fine endorsement, Ray! I think the original arm would have worked ok in this case, but the cable would need to be attached by other means, like the previous owner did. I do tend to get carried away on projects like this, trying to get everything just perfect, sometimes to the detriment of getting the job finished. Hopefully that won't happen in this case!

I have to admit I don't know much about the new Whizzers, other than what I've picked up in researching the older ones. In a way it sounds like the old Whizzers might actually be easier to work on.
Dunno.gif


Paula

All this Quality!! really makes a person appreciate whats available to us from guys like Joe Cargola,Fred White, Ron Houk, Fred Koeknke, Ralph Westman, others like your self. I really need to get busy and start one of my vintage bikes. I've been doing mods with my new edition whizzers, the clutch arm needs to be made right. maybe?

Can't wait to see the next phase of your project!

Ray
 
Don't feel bad -- it's exactly what I was looking for. A project that would be enough of a challenge to make it worthwhile, but not a basket case that would overwhelm me.

In all honesty, this bike doesn't really "need" this much work, just depends on what you're after. I tend to start out with modest standards which inevitably rise as I get into the project. A balance definitely needs to be achieved.

Paula

Exceptional work Paula. I feel bad for saying this but I am glad you stumbled across a bike that needed so much work. Keep the pics and details coming.
 
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Paula,
No need to apologize for trying to make things to your satisfaction! Your high standards of quality have really stood out. I continue to be amazed how at each turn of your thread, like this fabrication of a little itty bitty clutch arm, it is just like watching the creation of fine art in front of our eyes!

If there could ever be a thread that defines the total and complete restoration of a vintage Whizzer Motorbike, I believe we are all witness to it right here!

Plus, looking at all those fancy shop tools is kinda neat, too!:D

Take Care,
Mike
 
What Mike said! i gotta learn this sweet talking thing.

Ray
 
Hi Paula,

Great details on your project.

The vintage Whizzers are by far easier to work on. The American quality is always evident when taking the motor apart, as the bolts & nuts can actually be removed without major damage.

During the upgrade or rebuild process on new edition motors there are always bolts & nuts that strip out, and often the threads in the cylinder and crankcase must be repaired.

Have fun,
 
Clutch Pulley

Once again, thanks to all for your nice comments and support!

With the clutch arm finished, it's time to consider the clutch pulley. This is the 2-step pulley which bolts to the clutch arm, and transmits torque between the engine pulley and the rear wheel. It is fairly easy to remove the pulley by taking out the 1/2" bolt which threads into the clutch arm. There is a spacer, or sleeve, to center the bolt in the 17mm bearing I.D. The ball bearing is held in place with an internal-type retaining ring. Here is a view of the clutch pulley components all disassembled:

PULLEY01.jpg


The pulley on this bike is of the composite type, made up of spot-welded steel sheave components and a machined steel hub. The bearing is locked in the hub with an internal retaining ring. The ball bearing on this unit doesn't seem to have any significant wear, but the lubricant is pretty well dried out. The bearing itself (#9017DD) is something of an oddball: It has a metric O.D. and I.D., but a 9/16" width. (More about this later.)

This pulley is kind of rough, but could be brought back to decent condition with some effort. Nevertheless, I elected to spare myself some work, and purchased a new one. I went with a machined aluminum pulley from Memory Lane Classics sells. I must report that the quality of this item is superb. I also purchased a new bearing for the pulley.

One thing I wanted to do right off the bat was replace the troublesome thin-type retaining ring with a more robust standard type - the kind with the holes for a retaining ring pliers. I've found that it's nearly impossible to remove/install the thin type without boogering up the works. So I bought a 40mm internal retaining ring, but I would need to widen the narrow groove in the pulley. With the pulley chucked in the lathe, the ring was widened out just enough to fit the new retaining ring:

PULLEY02.jpg


The new ring was test-fitted with the pulley still in the lathe:

PULLEY03.jpg


Getting back to that oddball bearing. I wasn't able to find that size bearing through any of my usual sources. Apparently, neither was Memory Lane, as they sent me a standard 6203 metric bearing. This bearing is identical to the original Whizzer bearing, except for the width. The Whizzer bearing has a 9/16" width, while the 6203 bearing has a 12mm width - some .090" narrower than the Whizzer. Interestingly, the pulley I bought from Memory lane is bored for the 9/16" wide bearing, so... a dilemma.

I decided to go ahead and use the narrower bearing, as I believe it is fully up to the task. I would simply need to make a .090" thick spacer to compensate for the width difference between the two bearings. Also, I would need to decide whether to locate the spacer on the outside (retaining ring side) of the pulley, or the inside. Locating the spacer on the inside of the pulley (the engine side) pushes the bearing further out from its normal location, but also more centered between the two sheaves. This is a good thing, as this type of bearing is best suited to pure radial loads, and less suited to oblique or thrust loads. The only downside is that I would need to modify the sleeve which centers the bearing on the 1/2" bolt, adding a small step on the engine side to make up for the thickness of the spacer in the pulley. Not a problem.

I found a piece of aluminum in the scrap bin, and began carving it up to make the spacer, starting with a large drilled hole:

PULLEY04.jpg


From there, the I.D. was opened up with a boring bar, and the O.D. turned down to just a tad under 40mm. The finished spacer was then parted off in the lathe using a rear-mounted cutoff tool:

PULLEY05.jpg


After some light deburring, the spacer can be slid into the bearing bore of the pulley:

PULLEY06.jpg


Now the new bearing can be installed using the arbor press:

PULLEY07.jpg


Here's a view of the installed bearing from the back (engine) side, showing the spacer...

PULLEY08.jpg


...and view of the front side, with snap ring installed:

PULLEY09.jpg


Now all that remains is to make a new centering sleeve with a small step, but that job will be deferred until I have the flywheel installed. That way I can make sure that the step is the right thickness for the engine pulley to line up with the clutch pulley.

Paula
 
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Compression Release

This engine came with the familiar type of compression release, typical of those found on the J-model engine:

CR01.jpg


The body consists of two sheet metal stampings spot-welded together. The actuator (the part that pushes against the washer on the exhaust valve) rotates in an eyelet, of sorts, crimped at both ends to hold it in the body. The lever is swaged to the outer end of the actuator. In this particular case, the lever must have been removed, or fallen off, as it had been soldered back in place.

With this design, there is no provision for any kind of seal to prevent oil from seeping out around the actuator shaft. This should not be a problem as long as the engine is fairly "tight" (piston rings still sealing well), but excessive piston blow-by could cause a significant oil leakage problem. See the following thread for a discussion of this issue:

http://www.motoredbikes.com/showthread.php?25942-Compression-Release

I would like to avoid this kind of problem, so I decided to try and incorporate some kind of O-ring seal. Unfortunately, the older style compression release body doesn't really lend itself to such an upgrade. But the newer style, the cast aluminum one with the fins, has some possibilities. In addition, it has a torsion-type return spring, allowing it to be used with the trigger style compression release control. I wound up purchasing one of these units from an eBay seller with a well-deserved reputation for spotty quality:

CR02.jpg


I was expecting poor quality, and they didn't disappoint. The lever on this unit looks like it was stamped from furnace duct material, and is attached to the actuator by simply pressing it on. It came off easily the first time I moved it slightly. The shaft on the actuator is rough as a cob, and the corresponding bore in the body is at least 1/32" oversize. Fortunately, the aluminum body and torsion spring were nicely made, and that's all I really cared about, since I would be fabricating the remaining parts.

My plan was to enlarge the hole in the body for pressing in an oilite bronze bushing, leaving a small recess on the inside for an O-ring. I would make a new actuator to fit the bushing and O-ring, and a removable lever, so that the O-ring and bushing could be replaced at some point, if needed. I made a drawing in Solid Edge (CAD software) to establish dimensions for the new design. Here is an exploded view showing the assembly (click on the small preview to open the full image):



The O-ring shown in the picture is orange colored because I am using a silicone O-ring. Silicone O-rings have a higher temperature rating, which I thought would be a good idea, due to the engine heat. The size of the O-ring is 1/4 I.D. x 3/8 O.D. x 1/16" thick (Note: these are nominal dimensions; actual dimensions allow for the correct amount of compression in a recess sized to the nominal dimensions.) The oilite bronze bushing is 1/4" I.D. x 3/8" O.D. x 1/2" long. The new lever would be fastened to the new actuator with a 5-40 x 1/4" long stainless phillips-head screw. I'm also adding a clamp-type cable connector to the arm, which permits the use of a stranded cable in lieu of the solid Bowden-type cable.

(to be continued...)
 
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