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this page was edited 8/3/09

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On 08/03/2009, at 05:20, Jon B. Shereshaw wrote:

Dear Sir: You are one of the most creative people on the
Yahoo Group.  I Have a 1967 BMW R60/2 with TR-500 Steib
Sidecar.  I have spent about the last 10 years restoring it.
(And Many Many Bucks!)  I really like the addition of that
SKF bearing on the Crank....It makes complete sense... I
sent my lower end down to Benchmark Works a couple years
ago...and he found the dreaded problem of rear brearing
spinning in its seat. Anyway, to make a long story short -
Got it back..Paid the Dues!..assembled the rest of the
machine...It runs great!...I have about 750 miles on it
since.... I noticed the oil filter that you have installed!
Nice piece of work! Can you tell me where to get one???  I
saw one a couple moths back on the Yahoo group...The guy was
running them in small batches..I was doubtful though ...
that the oil pressure was enough to penetrate the
filter...especially when getting a little dirty....You
thoughts on this????  Currently I have A SUPER MAGNET that I
bought from Benchmark Works and Epoxied to the Alum oil
pan....seems to be doing its job...Could you comment on all
this??? Sincerely, Jon B. Shereshaw New Jersey, USA

***

Hello Jon,

Thank you for your compliments!

Re the oil filter: my motor has run 7000 kms with the oil
filter now, oil changed every 1000 - 1500. Every time I
back-flush the filter to investigate what it catches,
I'm surprised how much debris there is, predominantly
little silver alloy flakes. It appears to be the same kind
of sediment that one scrapes out of the slingers. So I'm
sure the filter does its job well!

I did my own flow tests and I'm entirely satisfied with its
performance. I am so confident in the design, that I now
leave the filter in over 2 oil changes. Even after that
there is no measurable reduction in flow. It really is not a
problem to have it in the oil supply circuit and it has so
many benefits. Peter G's filter adapter (I think it's the
one you refer to) is based on my design and I have
collaborated with him. He has done much more thorough
testing then I and came to the same conclusions. I have one
of his adapters and will mount it at the next occasion. It
has an advantage over my design - the oil level can drop
even further before the pump will suck air. With his adapter it
would be safe to run the motor with oil just below dip stick level!

Jim

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added 15/03/08

this is a most insightful exchange on the slash2 yahoo group - I asked a question
about camshafts, got a good answer but then it goes off to another very interesting topic...
(this relates to 1955 to 1969 R50, R60 and /2 models - not the S models)

Perhaps the knowledgable members can shed some light on this
issue. I believe the Earles models all had the tilted cam
profile to facilitate the turning of the lifters. I remember
reading about that feature being introduced during
production of the R51/3. But there is at least one other
difference. I have obtained a (later?) camshaft with a
narrow cam - about 2/3 of the width of mine from a 1959 R60.
The cam lobes also have a different spacing (positioning of
their centre lines along the shaft). Most other dimensions
as well as the shape of the cam appears the same, the slot
for the key seems a few millimetres moved forward. I have
not found a comprehensive piece in any of the literature
about the different cam shafts used - yellow, red and black
dot markings are also used on them.

Jim

Answers:

The cam lobe width and spacing was changed with the introduction of the /2
series of engines.

Richard




The narrow lobe on the R50/2 was set slightly off center to the cam follower to
cause the cam follower to rotate so that wear would be more even. The cam
followers had a radius on the contact surface. It was .75 Meter

Yes, I believe the cam timing was slightly different between the R51/3 and the
R50/2, the latter being slightly advanced and longer duration than the R51/3.
That is from memory, and can be either verified or disproved with a little
research.

Advanced cam timing equates to a power band developing at higher RPM, earlier
timing at lower RPM and possibly over a broader range. Depending on what you are
going to do with your bike should help you decide which cam to use.

Not sure that either lobe had much effect on pitting. That was mostly a
metallurgical problem with the cam followers and sometimes with the cam lobes.
If you have the early type follower with four supports, exchange them for the
later type with two. They are less likely to break. Yeah, I know, a hundred
bucks a pop is a lot of jingle jangle. It's still cheaper than a tear down and
subsequent repair.

Richard



They are convex. The hard face on them is quite deep. Best not have them heat
treated. You might have trouble finding a shop set up to grind a radius on them.

If you now have the type with four spiral slots on the side, put them up on the
shelf and buy new ones. The older type were prone to collapsing at the most
inopportune moments.

Richard



I would only buy new Mobile Tradition lifters (cam followers or
tappets). The concern about lifter pits is the hardness of the removed
material and how long the tiny bits might circulate in the oil before
being slung or settled. With the cam faces, it's the hardest steel in
the engine.

My R60/2 had two pitted lifters so in the rebuild I sent them to Korn
for refacing. He had them built up with new metal, which was then
ground convex and hardened. After 300 miles the cylinders had to be
removed for a piston ring problem, and the refaced lifters were
already pitting. One lifter had one pit, the other had a cluster of
pits. I returned them to Korn for refund, and ordered two lifters from
Huggett. Korn then borrowed the Huggett lifters for comparison with
his grinding and hardening (interested in the Rockwell), and returned
them for installation.

During that time I corresponded with Mark Huggett on the subject.
Re: tappets
Written by: Mark Huggett on 2/1/2000
The tappets or cam followers with the end numbers 102; 104 & 105 are 4
window cam followers with flat cam surfaces. These cam followers are
nice and light, but tend to break between the windows. The cam surface
also tends to pit. BMW replaced these with the new cam followers with
the end numbers 127; 128 and 129. These had two windows and a very
slightly convex cam surface which results in a rotation of the
camfollower during operation.
We can only warn you against a good looking but very inferior quality
cam follower on the market at present as they will result in motor
damage and destroy the ends of the pushrods. If you buy new, then only
original BMW parts from your official BMW dealer which are
manufactured by us for BMW. They are expensive, but worth it....
As we manufacture the original cam followers right here in Switzerland
for BMW, we have alot of experience and work to the original BMW
specs. It is a complicated casting with nitride hardened surfaces and
soft walls. It is a science and a complicated and expensive process to
manufacture such an unimportant-looking little part. Instead of going
into an extremely complex explanation and details, I ask all who read
this to just except and respect the fact that this article is to be
taken most seriously and don't buy cheap and destroy your motor.

(no signature)



I have probably had a 1000 of those lifters in my hands.  I have seen a few
failures.  Nearly all are due to pitting.  I shouldn't say that they failed,
but they were replaced before they caused trouble with excessive cam wear.
I have seen very few cam lobes worn off.

I only remember one bike with a collapsed lifter.  It was the 4 window type.
It did not ruin the bushing.  I have found a few (5-10, can't remember) that
had cracks across the support almost at the end.  They were all in the same
place.  If you call the "hole" a window, then this would be the window
frame.  They hadn't failed yet, but I felt fairly lucky to have noticed them
in time.  Think how awful it would be to have a new top end job fail from a
lifter.  It would actually be unrelated, but would a customer understand it
that way?

If I were rich, I would sell off my non-pitted 4 hole variety on eBay and
buy the much stronger two hole variety.  In my experience, the risk of
failure is not great.  However, I prefer zero risk.  If cash were a problem,
I would use them and inspect after 20 k miles, or so.

Duane Ausherman

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Answers to various questions put to me:

* Oilfilter: I use Mobil 1 - 5/50 which has very low viscosity when cold.
I did flow tests with a 10 cm pipe of similar diameter as the internal
gallery with and without the Honda filter at room temp using gravity.
The difference in flow was less then 5% (105/100). I also compared the
time it takes to accumulate an amount of oil in the head covers which
relies entirely on splash AFTER the oil has gone through the oil pump.
There was no measurable difference.
My filter arrangement fits with the standard oil pan. It requires a minimum
of 0.8 litres to safely cover the filter element. In other words, if the
oil level is held above that quantity there will be no starvation.
I prefer the smaller oil volume with the standard pan and rather change the
oil often - every 1000 kms I refill with 1.9 litres of Mobil 1. My engine
does not use any measurable amount of oil during that distance. I ride in
hilly country, so I open the throttle often all the way, but I avoid revs.
I don't ride any faster than 120 ks/hr if I can help it. Mostling cruising
between 80 and a hundred klicks. But that I do for hours.

* Generator: I'm happy with no working charger at this stage. It seems
absolutely no hassle to keep the battery charged manually. Remember,
igniton is by magneto and doesn't rely on a battery and with LEDs used
everywhere there is hardly any capacity requirement. The only real drain is
from the headlight which I rarely use.

* Parts from different bikes used: the front fork is R26, the gear cluster
is of R25/3 and the crank is R68 with modified bearings (see Motor section).
Crank case is R60/2, frame is early R50 (small battery tray), drive R69S.
Left header is made from a slash 5 header and there are many small bits that
are unaccounted for.

* Slash 5 side stand: I removed about a millimetre in width at the hinge end,
so that I could fit the split pin and a fat washer easily. I used a longer bolt
with a nut to replace an oil pan bolt to attach the spring. The foot sits nicely
under the foot peg when retracted - its such a neat solution, I'm surprised
I haven't seen this before. This stand works extremely well and doesn't
have the tendency to make the bike unstable when on uneven ground as the
OEM stand does.


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--- In slash2@yahoogroups.com, "Andy A.." <djaview@...> wrote:
> There are a whole handfull of good ideas in the photos.  Does the
filter affect the flow of oil?  How did you fabricate the large
magnet oil plug?
> Jim, you might consider adding a parts list to your site.  Your
designs are worth sharing.

* Thanks Andy for yor kind comments. I only just started the site and will
take suggestions into account. Keep checking, I just added a new page.
The magnet is from an arts supply - incredibly strong and it really collects!
I just drilled an old plug and pressed and superglued the magnet into it.

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On 13 Feb 2008, at 07:49, Bob P... wrote:

> Congrats on getting the old girl back on the road... a labor of love, for
sure.  I like your seat, and what a clever way to keep "little things" in the
two leather pouches!  I have done a lot of little stuff to my bike, but find
myself wanting to get into it more and more... might have to find another
one to work on!
 
> We have all benefited immensely from the slash2 group:  I just lurk and read,
and then go do things on the bike.  I have replace shock bushings, lots of
rubber bits, lots of stainless bits, grips, cables, etc etc.  I am lucky in
that I have Hucky here in town, so I can go over and talk to him while he
rummages for the parts I need... what a treasure to have these BMW gurus at
our fingertips with the internet!
 
> I have a 1966 R50/2, which I am realizing, more and more, was extremely
well cared for over her lifetime, so I am doing little things to keep her
going.  Love riding the bike, and the comments never stop, wherever you go,
do they!
 
> I installed a new Corbin solo seat, found an old accessory chrome rack
(to which I have, very un-gracefully, strapped a tool bag in which to carry
my tools, flashlight, bulbs, etc since I don't have a key to my tank locker),
then splurged on a repro rear fender rack, to which I attached a foam
pillion seat.

* thanks Bob for your comments. I agree, the old Rs are a great inspiration,
they draw you into their realm. I think it's the spirit of the engineers
that gave these machines a soul.

My leather pouches have in it: band aids, cable ties, puncture kit,
adhesive tape, fuel additive and the key to the tool box. I should spread
all that out and take pictures - I can do most maintenance on the road if
I have to.

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