Brake shoes

Removing the brake shoes was a bit more difficult than I anticipated. The trick to getting them off the backing plate comes down to expanding the shoes about 1/4″ on the actuator side and then pushing the actuator pivot through the shoes. Next I used a screwdriver to wedge one shoe off the fixed pin and then the other shoe. The springs will not come off until the shoes are off the backing plate. This is backwards to what I am used to when working on automotive drum brakes.

Most of the rivets are about 1/64″ loose and it looks like I can buck them up tighter without removing the lining. Looks like I can get 1/32″ clearance on the 3 rivets that are currently flush with the brake lining face. 1/32″ will be enough to use the shoes as is for awhile since I rarely get going fast enough to use the brake in the first place. The lining from McMaster Carr showed up and looks correct but the smallest rivets McMaster Carr had were larger than the rivets on the shoes so I did not get them.

Frame paint stripping

OK, the yellow paint is off. There is still a lot of Hunter green and red oxide primer to remove. The original green paint is burned away at the 2 vertical braces between the lower frame rails and rear wheel stays. It is also burned away at the front engine mounting tabs. I expected to find this. I also found paint burned away and disk grinder marks on the bottom of the main tube under the gas tank. Maybe they tried a front engine mount here and then realized there was no room for the carb???

The big surprise is that the green paint is also burned away at the 4 bolt stuffer mount bracket. Also the original welds are nice, tight TIG welds. The welds used to add the later parts look to be much larger stick welds. Now I suspect that the original engine mount was the 2 5/16-18 UNC under the clutch bolts and the 2 1/4-20 UNC fan shroud bolts. This also explains the torch cuts through the side mount bracket to allow access to the left side stuffer bolts. I had to make the upper torch cut larger to get an Allen wrench on the bolt. I have no idea how they put the engine in this thing. Could they have bolted a partially assembled engine to the stuffer mount and then welded it? As bizarre as that sounds my 1968 Bobsy Vega race car required the engine to be assembled after the short block was installed in the chassis.

The bare frame weighs in at 27.2 pounds. Here is one of the front engine mount cracks.

Engine Mounts

Nethercutt was obviously experimenting with different ways to mount the West Bend Power Bee 820 engine in this bike. It has 4 different sets of mounting bolt patterns on it. It has the MK2, MK3 and MK4 4 bolt stuffer bolt pattern that requires removing the Albion to get at.

It also has the MK5 and MK7 behind the clutch bolt pattern that requires removing the clutch to get at.

I used special washers for the flat head screws.

The bike did not originally have the front mount but Jim Cavanaugh said that it was added because the bike shook too much without it.

The 3 patterns above were used when I received the bike. One stuffer bolt was missing and one was loose which allowed the stuffer gasket to blow out creating a lean mixture and very high idle. It also has a 4th unused pattern that picks up two of the fan housing bolts. I tried this back when I was busting the fan housings with mounted kick starters, Looks like it was a bad idea back in 1962 also.

The stuffer and behind the clutch bolt patterns can’t be used together because you can’t draw both up and properly seal the stuffer gasket. I chose to use the side mount and not the stuffer mount to make it easier to remove the engine. I replaced the West bend logo stuffer plate with a non logo one that I countersunk for flat head screws.

Override

The override seemed to be working correctly when I first went over the bike. I lifted the front wheel off the ground and the front tire easily turned forward and locked up a little slow in reverse. I turned my attention to the poorly running engine which turned out to be a blown stuffer gasket. Once running correctly the bike steered smoothly and pulled my steep test hill with ease so I figured the override was in good shape. Turns out the override was NOT in good shape.

Both miter boxes feel smooth after removal with no metal coming out on the front magnetic fill plug and a very small amount on the rear. If a lot had come out I would have pulled the driveline apart for an inspection and found the swallowed override spring. The rear miter box tab is bent back maybe 1/4″ with about 1/2″ of the miter box sticking out of the frame tube. That was an obvious clue something was wrong but the dirt line on the miter box showed that it was this way for a very long time. I measured .669″ of spring stuck between the override hubs so the math does not add up. I think maybe the spring got sucked in and they did not catch it. Looking at how the blank left side end miter box cap in the old MK0 picture is clocked compared to what came with the bike I suspect the front miter box was replaced at some time. The 3 bolts holding the driveshaft bearing in certainly did not let the driveshaft move forward which normally is what wipes out the front miter gears. Maybe the 3 bolts were added later?

The override hubs are retained with 1/4″ split pins. The rear hub is very close to the miter box so I thought it must have busted the pin and slid back when the spring got swallowed. A small Allen wrench went straight thru the rear split pin so this is obviously not the case. I was planning on just replacing the override spring but SURPRISE! the hubs have an outside diameter of 1 7/8″ instead of 1 3/4″. This means a stock spring won’t fit and it is unlikely that I will find a left hand wrap spring for 1 7/8″ hubs. I have 4 options. #1 Have a couple custom springs wound. #2. Turn the hubs down to 1 3/4″. #3. Replace the override assembly with an old unlocked one. #4. Replace the override assembly with a new locked override.

Driveshaft bearing

The driveshaft support bearing is a R12-2RS just like all bikes made up to date. It is mounted between a 1/4″ diameter split pin in the rear and the flange of the bearing carrier in the front. The carrier has a full 360 degree outside diameter instead of 4 flats like later bikes. It is fastened with 3 1/4-28 UNF bolts spaced roughly 120 degrees apart. The frame tube and bearing were drilled and tapped in assembly. That means the frame tube also has threads. The bearing support is not adjustable front to rear like MK3 and later bikes are.

RAVE II

The RAVE II report did not have the MK0 but it did have 2 MK2 bikes. The test is dated June 13th, 1963 and is the last test that I found on the Nethercutt bikes. The mule is on page A1 and the MK2s are on A-5 and A-6. Looks like the 30 year old mule showed up late and missed area A but did better in area C and the swimming part than the MK2s did. The test was held at Tomahawk Hills Pontiac, Michigan.

Fishmouth repair

Since the bottom 1/2-20 UNF kingpin mount is cross threaded and misaligned I am going to drill and tap it oversize to 9/16-18 UNF. Usually the threads are just stripped and I will level the kingpin bolt hole axis and use the bubble level on my drill motor to drill the hole true to the kingpin bolt axis. Drill bits tend to follow the existing hole so this method will only make this mess worse. I need to fixture the frame to straighten out a hole that is off front to rear and side to side. I started by putting an 8″ 3 jaw Buck chuck on my drill press. Then I chucked up a 33/64″ drill bit, lowered the drill bit into the chuck, chucked it up and then bolted the chuck to the drill press table. This aligns the drill bit to the kingpin bolt hole axis.

Next I threaded a long 1/2-20 UNF grade 8 bolt into the top kingpin bolt hole that is still in good shape. I will use this bolt to line up on.

Now the frame is loaded upside down with the long bolt going into the Buck chuck. The frame is far too heavy to support by just the bolt so I have to move the drill press and frame over to a chain hoist to support the rear of the frame.

Drill the hole.

tap the hole.

Done. The thread alignment turned out perfect with at least 80% of the threaded hole cleaning up.

Fishmouth

I noticed that the lower kingpin was misaligned on day one. I was able to snug up both bolts and the little bit of play I saw was not that bad so I put off taking it apart. Once apart I can see the original threads in the bottom were probably correct. It was tapped again offset which is what is shown in the pictures.

Kingpins

It looks like both kingpin bolts were made out of existing hex head bolts. The top kingpin has a 15/16″ hex and is drilled for safety wire. None was installed. The shoulder is only a few thousandths longer than the bushing. I found this can create the problem of the bolts backing out during use. I thought the top bolt was drilled and tapped for a grease fitting. Turns out it was only center drilled. The bottom bolt has a 7/8″ hex and the shoulder is about 1/32″ longer than the bushing. The threads come up about 1/4″ short of the shoulder so the kingpin jams on the 1/2-20 UNF threads instead of locking up on the shoulder of the bolt. The threads are about 1/4″ longer than the top bolts threads.

I put SAE 841 sintered bushings on for the picture. I also have Delrin and SAE 660 bushings in stock.

The top bolt is on the left, the bottom is in the middle and one of my oversize thread bolts is on the left. I am going to have to use an oversize bolt in the bottom because the fishmouth is cross threaded at least twice, maybe 3 times. Ughhhh

Air filter

I noticed something was weird when I took off the air filter. Turns out they used a single offset air filter base, filled the original holes and then drilled new holes to make it a double offset base like the MK2s, except they did not center up the base with the carb. The carb was about 30% restricted on my first test ride. Kinda like riding with the choke part on. The Case diesel water separator air filter is the same as the MK2 and MK3 filters. I stuck on a correct MK3 base, a paper air filter, filter clips and Wacker tamper cover for subsequent rides and pressure washings.

The cover is marked WEST BEND and is dimensionally the same as later covers. I will put it back on when the bike is closer to getting finished. Not sure if I want to use the Case filter. Flow bench testing many years ago showed a big air flow loss compared to any other filter. The base attaching screws are drilled for safety wire but none was used. I did use safety wire when I put the base back on.