October
20, 2001. I wet-sanded my painted frame with 1500 grit paper and then,
gave it a final hand polish with fine scratch remover. There was a
paint run near one of the passenger peg mounts, so I used a razor blade
to level it, sanded it, polished it--and it's gone. Vech installed the
centerstand on the frame and we sat this "skeleton" on one of the
rolling work tables. All of Vech's work tables have wheels so he can
roll them into and out of the shop. In Mississippi, the summers can be
sweltering hot and the shop air conditioner is a necessity. Although
winters are mild, there is still a need for heated space in order to
work. The rolling work tables solve the problem. The tables have
storage space beneath them so it's easy to keep all of the bike's parts
together. We keep a clipboard on each table to document work and parts
used so that at the end of the project we can calculate the restoration
cost. I spent the weekend bead blasting, sanding and priming small
parts. I have a collection that is ready for black paint.
I
saw a program on television about modern inventions people love to
hate. I think needle bearings should be added to that list. I unwrapped
the rear end and Vech gave me a package of needle bearings to install.
We used lovely pink grease to hold the needles in place as I arranged
them. When I finished, I noticed there were only 27 needles. Seems
there should be an even number and sure enough, one was missing. Vech
gathered a new bearing from stock (a $55 bearing, I might add), heated
the case and (after dumping the loose needles several times and having
to re-install them), installed the new bearing race on the shaft. When
he installed the shaft into the case, the shaft wouldn't turn. Vech
figured out that the portion of the pinion shaft that the race mounted
on was too large and caused the new bearing to bind. He removed the new
inner race and damaged it in the process. After much thought, foul
language, measuring, trial and error, Vech removed about .0005 from the
pinion shaft. He used emery paper to sand it, then he polished the
shaft on a buffer. When the measurement of the pinion shaft was
correct, he installed another $55 bearing (we're up to $110 in bearings
now). Thank goodness, it worked. It was one of Vech's "Damn, I'm good!"
moments. That tiny difference was enough to be the difference of the
bearing turning free or binding. Vech commented that a 4-inch rod won't
go into a 4-inch hole. Never thought about it before, but it's true.
There has to be a minor difference in size for anything to fit properly.
I
asked Vech about the purpose of the hole I have marked in red in the
photo. He said that the hole is to let oil drain out in case of
ring gear seal failure. In the event of seal failure, this hole helps
keep oil off the brake shoes. As far as oil on the ground goes, most
antique motorcycles are noted for oil leaks. Even the modern URAL
motorcycle constantly dribbles oil; not so with BMW motorcycles. BMW
motorcycles have a reputation as being the cleanest motorcycles made.
I'm really proud of the quality I see in BMW engineering. Just look at
the following photo.
 | Vech installed the external drive shaft on the final drive. He secured the drive shaft with a tapered pin which he drove through the universal joint yoke and pinion shaft. He secured the pin with a nut and also safety-wired it. He screwed (left hand thread) the aluminum bell cover onto the nose of the final drive and he shoved the white rubber dust boot tight against the bell cover. The rear end is now ready to install into the frame. |
 |
Back To Restorations BMW R51/2 journal, page 1 BMW R51/2 journal, page 2 BMW R51/2 journal, page 3 BMW R51/2 journal, page 4 BMW R51/2 journal, page 5 BMW R51/2 journal, page 6 |