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ScottA
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VBMWMO #7638
San Diego
Joined: 08/09/2007
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A few years back I purchased a basket case R27 in San Diego from the late Wesley Stark.

It was in boxes when Wesley bought it and he didn't have much of the bike's history to relate.
I've been aching to ride the single and now have time and space to work the project to completion.

Engine and frame numbers match and much of the preliminary parts-work has been accomplished but... not knowing where the work stopped... I've been taking what little has been assembled apart for review.

It was good seeing the slinger was clean.
The crank bearings appear new but bear no maker's mark so I assume they're cheap and I'm planning to replace them.
I sent the crank to Dan at CycleWorks and all checked within spec but for the connecting rod bushing which he replaced.
The crank sprocket was quite worn and I'm replacing it.
The cylinder was resleeved and required only slight honing to remove some axial marring, from the sleeving process?
The piston appears to be NOS and is sized appropriately. These two parts are currently at Bore-Tech waiting their turn for work.

I'm happy to see the good work previously done and also happy I'm inspecting it for shortcomings. My day job is inspecting turbine engines for aircraft and I've worked as a machinist, also I'm an A&P license holder.

Work is near home (5 miles) and I would like to use the R27 as a commuter on surface streets mostly but with the option of short stretches of highway on occasion, plus a trip to the hills now and then.

San Diego traffic is aggressive enough that I hope to improve the bike's performance within reason.
CycleWorks has lightened the flywheel for better acceleration and I'm considering further performance mods but remain on the fence somewhat while thinking of ease of starting and reliability, etc.

This bike has 25/6 final drive gearing.
The transmission may be the worst of the lot and I hope to have it open in about a week, am borrowing the proper Matra flange puller for this task.

So that's my introduction. Any insight or observations are welcome.
I'm working with manuals and the illustrated parts catalog but would really like to meet a local R27 owner to better understand the bike as I put it together. Twice I've seen a BMW single zip past my workplace but I was unable to chase the rider down.

Scott

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schrader7032
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San Antonio, TX
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Scott - Very nice

Scott -

Very nice project...glad things are working out and coming together. I don't know how much better the R27 is from my R25/2, but I have to be very careful when I'm out on my single. No freeways for sure and I really have to prepare well ahead of time for lights and traffic.

If you haven't, you might consider branching out a little to meet other single owners...there aren't that many around the US relatively speaking. Another Mono forum is at http://autos.groups.yahoo.com/group/bmw-mono-club/. One member there, Richard Sheckler, is very knowledgeable on these bikes. He lives in Ohio, so that doesn't help your situation.

Good luck. It will be good to see pictures as you get nearer to completion.

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'78 R100/7 '69 R69S '52 R25/2

ScottA
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San Diego
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Thanks Kurt, sounds like it

Thanks Kurt, sounds like it would be prudent to 'wait and see' before anticipating freeway runs in the style of Rollie Free.

On the plus side my morning commute is early enough that there are few cars along the stretch I ride. On the other hand it's dark at that hour and I'm thinking the glow of the tail light may be easy to overlook.

At any rate, it may be awhile before I see that action.

Good that you mention Richard as he's already been a great help with this project, even from as far away as Ohio.
I've posted infrequently at BMW-Mono-Club and have a few photos there in an album titled, "Scott's '61 R27". While the project hasn't moved much previously, I'm hoping to make good progress this year.

Bench Mark Works, S. Meyer and Hucky's have been good parts resources. So far I haven't had much luck contacting Uli's Motorradladen.
Betjemann's service manual has been an excellent resource though not single-specific.
Also, Allan Atherton has responded to some questions I've posted earlier elsewhere, mostly concerning /2s.
I was re-reading his R27 restoration story earlier this week... and thankful that this project appears less nightmarish.

Scott

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schrader7032
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San Antonio, TX
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From my standpoint, you're

From my standpoint, you're hooked into all the right resources. I bought one part for my R25/2 from Uli's...the hand shift lever on the right side of the transmission. All seemed to go well...it took a bit of time but they responded to emails when I had questions about the order. Worked for me.

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'78 R100/7 '69 R69S '52 R25/2

thicko
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Elgin IL
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R27 basketcases

Scott,
I just assembled a friends '63 R27 from parts of 2 basketcases that he owns. I can help if you need any detail pictures or my sequence of assembly, but it looks like you are pretty well along. I have never been on a BMW Single to help there and it is too cold and snowy here to start now. I'll start riding it in a few weeks and let you know.
Cheers Craig Bielat

  • r27-1911.jpg
  • r27-2511_3.jpg
  • r27-22611-2sm.jpg
ScottA
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San Diego
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Thanks Craig, nice pics

Thanks Craig, nice pics already.
Looks like I need to get me a persian rug for this magic carpet ride.

Any detail pics of the battery box innards would be most welcome.

Scott

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thicko
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Elgin IL
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Battery Box Details

Here you are, in the battery box. The terminal strip is held in place with cotter pins, 2 each. The Tail light harness enters in the top opening, the Brake Switch harness, with Battery Ground is the bottom opening. I chose a 6 volt 9 amp/hr Sealed Battery that is a bit smaller than the original wet cell battery, hence the felt shim under the strap. McMaster-Carr has them for around $25 + shipping. They are also great for stainless hardware.I hope this helps in your effort.
Cheers Craig

  • r27-22711_1.jpg
ScottA
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San Diego
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Thanks. Nice. Clean looking

Thanks.
Nice.
Clean looking installation.

Scott

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c.d.iesel
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Darien, Connecticut.
Joined: 08/08/2007
Posts: 363
on the road to recovery

Scott - you'll be fine out on the highway - unless the
nominal speed is 80 mph!!

60 - 65 cruising is comfy and givin the tight rebuild of your motor
you'll be singing right along

75 - 80 is the limit, unless your prone "under the paint"
then you will nurse 84 out of it.

here's mine - likely in need of your motor rebuild
in the near future - but I ride it like the wind
in the mean time.
Keep us updated
C.D. in Connecticut

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ScottA
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fodder for the peanut gallery

The cylinder and piston are back from Bore-Tech after receiving the carbide bore process and piston coating (some sort of molybdenum polymer?).
They also shaved .040 off the cylinder top.

The work looks so nice that I wanted to share. Seems a shame to button it up not to be seen again for many years (I hope).

My one concern at this time is whether the rings will seat nicely; the cross-hatching (which was fresh but not done at Bore-Tech, AFAIK) doesn't appear very "aggressive".



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ScottA
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San Diego
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thanks CD

I've certainly benefitted from your posts here and at the 2002FAQ.
Hopefully once my R27 is ready, I'll be able to participate in a Moto Giro event here in the west.

I've collected some of the (inspirational) pics you've posted of your R27, but sadly haven't seen as many as I'd like...

Scott

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jamesmoc
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Cork, Ireland
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Scott, I renovated a poor

Scott,

I renovated a poor condition R27 recently and have been riding it a lot for the last month. It cruises at 65mph and can hit 75 but that feels like it is pushing it a bit too hard. I think you'll be quite surprised at the bike's performance; I was expecting it too be far less nimble, not that it comes close to modern machines but then that is not what most of us like about these bikes.

I took a lot of pics and they are all at this site. My biggest problem was sorting out a flickering charging light on completion of project. It turned out to be a bad regulator and this was swapped for an electronic one. Since then it has run perfectly. If I can be of any help let me know but you will get a lot of detail through the photos at the link above.

James

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R.D.Green
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Same deal with me and my R27.

Same deal with me and my R27. Installation of an electronic regulator solved my charging problems and my "pulsating" charge light. Occasionally, when riding, the charge light will come on full, not "pulsate". When I turn the headlight off and then on again, the charge light always goes out. Need to find out what's up with that. I've had the bike up to 70 mph (indicated) a time or two but it doesn't seem happy there so I cruise it mainly in the 55 - 60 range where it seems to like to live best. The two lane country roads around here are perfect for it and it's quite flickable in the turns.

anderson7585
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Houston, Texas
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You folks are making me feel

You folks are making me feel better about my 1936 R2, it should be out of the Restorer's-shop later this year but I am/was really concerned with it's "performance".
I hold no illusions about Highway-work on it but I was having real concerns about it's surface-street capabilities.
BMW claims a top speed of 59MPH but I just don't see that happening!, I think 49MPH is a more reasonable expectation.

Vince

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1973 BMW R75/5 (LWB) "Griselda" (stock looking but with logical/practical improvements), 1971 Norton Commando "Commando Bizarro" (a truly strange custom project), 1936 BMW R2 "Ediltrudis" (stock, currently out getting a pro restoration). www.vinceandersononline.com

ScottA
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San Diego
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Thanks for the heads-up

Thanks for the heads-up regarding the charging system and regulator guys. I've been eyeing the available electronic replacement... we'll see how it goes.

Good to get those performance reports too. I anticipate being plenty happy with the whole package.
Nice to have all those pics available, James.

These singles seem relatively few and far between, judging from online resources.

Scott

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bimmerwork
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san diego, ca
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R27 owner in san diego

hi Scott,

i live in mission valley and own a '61 R27. i know i'm kind of late, but i just saw your post. if you need a look-see get in touch. you can even have a comparison ride, mine is mechanically all original though. sounds like yours will be a little faster...

send an e-mail, i'm around the house most of the time.

Will bimmerworks@mac.com

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bimmer owner since 1968, beemer owner since 1974 (a 1961 R27) several since then... still have the '61 R27 and the '68 2002... have restored many BMW 2002s, 3.0 cs coupes, Isettas, & motorcycles.

ScottA
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VBMWMO #7638
San Diego
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Cool

Will,
Awesome.
looking forward to meeting you & seeing the bike.
I'll shoot you an email.

Coincidentally, a couple days ago a friend offered an old R27 frame to me.
He doesn't have any money in it (traded some track tires for it) and is asking me what I'd give him for it.
I'd trade him parts but we don't own similar bikes.

I'd like to give him some money to make the transaction good & fair... trying to figure out how much would be appropriate...
can't assume anything about the frame is "straight".
The left frame rail aft of the centerstand appears to have a slight 'wow' in it from aggressive jumping on the starter, etc.

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ScottA
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San Diego
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gearbox

It's been a year since I made progress with the R27, now it's back on the #1 maintenance slot.
Picking up where I left off with the gearbox inspection and bearing R&R.

All is looking better than I had any right to expect. Even the bushing to gear bore clearances are all within spec.

It's been suggested that I install /2 solo gears for the taller 1st and the shorter jump from 3rd to 4th.
This has been recommended in conjunction with the 27/6 final drive gearing.

However, I have the 25/6 gears, so I'm wondering whether the tall 1st may be a bit too much. On the other hand, I'm expecting a bit more compression (1mm shaved off the cylinder) and I'll be running a lightened flywheel (CycleWorks).

Currently thinking if I can find /2 trans gears for a reasonable price, then I'll give it a try.

As I've said before: no plans for high-speed runs, just hope to get off the line respectably at traffic lights, etc..

Actually, assuming the gearbox has seen previous work (Federal bearings, etc), I'd better confirm what gears I have.
-edit: just checked. 1st is definitely 5.33, standard gearing

-Scott

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ScottA
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San Diego
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more gears

a few weeks ago a for-sale ad came up in the slash2yahoo-group for a '60s basket-case bitsa beemer twin: pick-up only and a couple hours away. I brought it all home, including the /2 solo gearbox Smile

And this titled '63 R69S frame; I see a conversion coming together.

The next weekend a friend long-term loaned his 12-ton press, putting me in business.

John's bike and his press in the back of my go-getter.

/2 transmission not all bad

gears you want!

yes there's a little rust and pitting. not enough to stop me. I can always take it back to the original gearing.

this is a great tool to have on hand

here we have /2 gears on R27 shafts with /2 intermediate shaft

waiting on parts and checking out the selector forks adjustment exercise.

the overshift adjustment took me a while to understand.

This evening I figured it out. It didn't help that the current clearance on mine is closer to .2mm.

I hope those other parts arrive tomorrow.

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schrader7032
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San Antonio, TX
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Is the VIN on the R69S frame

Is the VIN on the R69S frame listed on the BMWVMCA Orphan List?

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'78 R100/7 '69 R69S '52 R25/2

ScottA
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San Diego
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orphans

I posted both frame and engine (R50/2) numbers to Richard but haven't heard back or checked to see whether they've been added yet.

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schrader7032
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Usually Richard sends that

Usually Richard sends that info to me...if he did, it should be up.

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'78 R100/7 '69 R69S '52 R25/2

ScottA
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San Diego
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now we're cooking

early today I adjusted the overshift per the manual.

It should have been easy but overcoming the staking, loosening the slotted screws and finding washers suitable for shims took some time.

My down-stop was worn and the specified 2mm gap had closed completely.
The up-stop wasn't quite that bad but I adjusted it to spec. as well.

here we see the focus is fine on everything except the stop's excessive wear mark.

The fix was simple but not so easy. I'm happy with the results and hope it works!

Now to pull the gear cluster and shift yokes for final assembly.
'found this rotisseire oven on Craigslist

I managed to get these in on the second attempt, only burning myself slightly

good that I found the shim plate
I've had this surplused anvil mic for a long time and thought I'd give it a try here.

Maybe tomorrow I'll figure out what shims to look for.

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ScottA
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San Diego
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Finally...

found some time and had all the parts in hand, today I closed the door on the gearbox.

working out the shimming was a bit of a chore.

after that, all went fairly smoothly.

once the cover was in place, when I turned the shafts it made a racket internally.
This produced both frustration and consternation plus a bit of panic before I realized the kick lever was engaged... pilled down for assembly. It was the kick ratchet making the racket.

shortly after snapping this pic I realized it was a little late for installing the output shaft key. It took a bit of fiddling but I managed to get it in the keyway and have since fit the flange into position.

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ScottA
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San Diego
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engine assembly

finished installing the crank this evening

next is the flange mit oil spout (NLA) which I believe will need to be lapped flat so as not to leak where it shouldn't.
Maybe a bit of sealant as well? Dreibond? Unnecessary?

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ScottA
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San Diego
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assorted sockets are handy accessories when using a press

after chilling the cam & sprocket assembly, then warming the sprocket with a torch, a 5/8 deep-socket made it possible to press on the taper above the keyway and remove the sprocket while leaving the spindle undisturbed.

This disassembly took a fair amount of pressure to initiate.

assembly was much easier

the cam sprocket is NLA. This new one is an Isetta sprocket, slightly modified.

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808Airhead
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Good job tackling the gearbox

Good job tackling the gearbox work!! Where did you get the gear plate?? Is it a cycleworks one?? I am goiong to be doing a gearbox rebuild next year and the pictures you showed make it seem straightforward. Good luck on getting it all done!!

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R69s - R60/2 - R67/2 - R51/3

ScottA
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^howdy, 808Airhead

Thanks, it was fun and educational. The next one will be that much easier.
Yes the plate was sourced at Cycleworks, one of my favorite suppliers. I bought the gearbox overhaul CD too, which was helpful though some details were beyond its scope.

I’m also in correspondence with Adrian in Melbourne who rebuilt his R27 gearbox not long ago.
His experience has been particularly valuable to me.

I hope you’ll keep us posted on your project.

Little time available last night but some progress was made: cam assembly is installed along with the CV timing parts. Fitting the crank sprocket is next... tonight maybe.

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ScottA
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bottom end

installed the timing chain last night. fairly certain the cam is indexed properly.
One description I hadn't heard, but appears to correlate: with the crank keyway at 12:00 (O/T) the cam key (also case breather indexing pin) are in line with the cam spindle and pushrod tubes.

Cycleworks lightened flywheel.

I'm about to install the clutch.
Not seeing any specs on diaphragm spring height. Mine appears slightly used and height measures 16.8mm.
I see they're NLA so I'll install it and see...

The flywheel's skim-cut floor would reduce spring pressure. I looked close and believe the cut was minimal, as required to clean-up.

top-end approaches

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ScottA
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San Diego
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rings

GOE?
I'm not familiar with this brand... is that a contraction of Goetze?

These rings were supplied by the PO, look unused and fit well... however I'm tempted to use KS or some other set of rings, simply because these look funny (to me).

Opinions? further information?... I'd appreciate any feedback.

I performed a Google search and found some results but not much conclusive.

thanks,
-Scott

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schrader7032
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Check with Vech...I think he

Check with Vech...I think he only deals in KS, though, but I'm sure he would know. I checked his website for parts...he only shows KS rings.

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'78 R100/7 '69 R69S '52 R25/2

ScottA
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San Diego
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Kolben Schmidt

I neglected to mention earlier that the cylinder has been treated to Bore Tech's carbide bore process.

S. Hamfist set me straight on this: not to use chrome rings (the "GOE" top ring has this appearance) but cast iron, such as the KS.

Vech was (again) recommended as a supplier and I ordered a set a couple hours ago.
I'm a regular caller. They're a great resource.

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That S. Hamfist really knows

That S. Hamfist really knows his stuff, despite his name!! Laughing

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'78 R100/7 '69 R69S '52 R25/2

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next

those piston rings arrived Thursday, looking good, and as of this afternoon I hope to not see them again for quite a while.

I installed the head and valve assembly just long enough to verify the piston doesn't hit the valves.
all is as it should be, through several rotations.

I still want to hand-lap the valves, which shouldn't take long.

For some fun, when the head goes back on afterward, I'll check valve timing with the degree wheel available from the files section of yahoo-groups' bmw-mono-club.

I suspect it'll be fine.

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Great work!

Well done Scott, love your work. My cylinder head has repaired threads both in the exhaust and in the spark plug, which now uses a 3/4" threaded plug like the twins.

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ScottA
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thanks Christos

this head is still set-up for short reach plugs, and I hope the exhaust threads will last a little longer.
Both give me the feeling of skating on thin ice. Wink

This afternoon I addressed the rockers.
The originals were worn at the tips, so when I saw Hans Lowe (http://www.bmwhucky.com/) offering a pair of good-used rocker assemblies I picked them up.

Looking more closely, I noticed the oil path differed in that the pivot pin was drilled & tapped for end-feed, whereas the R27 pin is notched at the headbolt scallop. After asking around and looking at the parts fiche, it seems the good-used rockers are originally intended for the plunger framed R25.

The rockers themselves appear to be identical, only the shafts needed swapping.
They're press-fit into the rocker blocks but easy enough to shift using a small press.

end-feed shaft on the left, shaft on the right notched in the scallop (also seen in the assembly at upper right) once through the notch, oil passes under the solid bushings along the machined flat, seeping past the ends of the bushings and out the rocker's weep hole.

Once disassembled it was apparent the bushings also differed. The older style is grooved and the channels coincide with the rockers' weep hole.

I kept the R25 bushings with their rockers, moving those onto the R27 shaft. End-play adjustment was easy as well.

This makes me happy. Smile

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coming along

engine installed last weekend.
good progress, still plenty to do.

laying-in the new harness is high on the list.

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ScottA
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San Diego
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OEM sidestand

I have an original BMW side stand for this bike and haven't yet figured out where its spring anchors.

It's obvious where the side stand end attaches, but if someone can relate where the frame end anchors I sure would appreciate it.

thx,
Scott

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ScottA
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this works

not sure it's the right spring, but the arrangement works as it should.

spring anchored at the cross-bridge here (and I thought the small hole was for drainage only).

not enough lean but I can fix that by increasing the bend angle

I think I like it.

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ScottA
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moving along

The project is back in my home garage, for convenience, and I'm laying-in a new wiring harness fabbed by the late Robert VanVliet.

It's feeling like the closer I get to completion, the further away I am from finishing.
I place an order with BenchMarkWorks weekly... usually just odd bits... this week's order is getting long with grommets and odd hardware, etc.

Last night I tried to set the ignition timing and was disappointed that I could not advance the points plate enough to get the points to close at the S mark. This even with the points gap set slightly greater than .4mm ...currently, at full advance the points contact half-way between O/T and S

(I'm using a multimeter set to measure resistance, one lead grounded to the engine and the other on the point's wire to the generator, which is disconnected from the generator.)

I should add that... since this was a basket case... I can't vouch for these parts' provenance. Additionally, the cam tip has damage were the advance unit indexes... meaning to say the D shape on the cam's nose is deformed slightly, now with only one good angle to index on. Also the ATU's D receiving hole needed a bit of reshaping. I believe both are adequate but am now considering replacement... pending a closer look into the issue.

This reminds me of Airhead77's ATU problems and the solution: http://www.vintagebmw.org/v7/node/10696#comment-26472
which Christos described to me in greater detail via email... and may be a good solution in this case, still more checking to do beforehand.

-Scott

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'61 R27, '63 R60/2 etc.

Airhead77
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Joined: 07/24/2013
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I know how it feels....

ScottA wrote:

........It's feeling like the closer I get to completion, the further away I am from finishing.............

I know exactly what you mean. You look at a weekend's work and think: hmmm, check valve clearance, install two grommets here, fix the small cabling error, put the tank and maybe I'll start the bike next time.

Only you end up going next time doing tones of work while realizing you need to order a few more parts .....next month maybe.

Your side stand by the way is AWESOME! I've never seen it before in any picture or catalogue.

As for the ignition timing, I was really hoping you wouldn't have to fight with it but at least the fix is easy and permanent.

Is your coil new? Do you still have the old one? If it is laying somewhere, I'd love to buy from you the cable retaining screw and grommet. I have borrowed mine from Ismo and I'll need to return them at some point.

Did you install the finned exhaust retaining nut for cooling purposes or it came with the bike?

P.S. Love your car in the background!

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Current: 1972 BMW R50/5
Sold: 1960 BMW R27
Christos @ Brisbane, Australia

ScottA
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VBMWMO #7638
San Diego
Joined: 08/09/2007
Posts: 296
hi Christos

Yes I have the old coil retaining screw and probably grommet as well. Shoot me a pm or email with your address and I’ll send it along.

I futzed with the timing some more last night and overcame some personal issues… happy to report all is well with the ignition timing.
The ATU was assembled 180˚ out and the wire to the condenser was binding in the pass-through to the generator, restricting anti-clockwise rotation of the points plate. I’m now able to adjust for points-opening timed to the S mark but the plate is at or near the limit of advance adjustment.

This makes sense as the cam is a bit retarded from factory nominal. Using a degree wheel I’ve determined the inlet opens a couple degrees late.
BMW spec for the R27 is 4˚BTDC +/-2.5˚ and mine opens at 2˚BTDC, near as I can tell.

This along with some damage to the cam spindle tip prompted me to ask BenchMarkWorks about the R27 sport cam they’re offering, which has greater duration and a little more lift.
I was told they had one in stock at the old price and so I (impulsively) bought it.

I guess the plan now is to break-in the engine using the stock cam, and once that’s all sorted, maybe get a dyno run before swapping cams, adjusting for the change and making another dyno run.

The pile of parts for this bike didn’t include a header nut, so I bought the similarly-priced finned nut.
In addition to oil supply worries, I’m concerned with heat dissipation so the finned nut made good sense… plus it’s easier to safety-wire to prevent loosening. Wink

Someone on the einzylinder forum mentioned making the valve cover gasket from copper sheet for heat transfer/dissipation to the valve covers, which sounds like a potentially good idea as well.

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ScottA
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San Diego
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parts interchangeability & Zündzeitpunkt

well... I thought I had it static-timed to the S mark... then remembered I'd opened the points gap to .5mm or so.
Once the points were gapped correctly, I was back at 2°BTDC (static) with the points plate at full advance. Sad

I've read speculation on the ein-zylinder forum that modern fuel burns faster than the formulas from the '50s & '60s, such that retarding the timing ~7° may be recommended. This suits my current predicament pefectly!

Then I recalled Bosco's thread wherein he reports the use of a /5 ATU with one cam lobe ground-off to substitute as a R27 ATU.
It occurred to me that I have a spare /5 ATU. I disassembled it to substitute the indexing plate for that of the R27, which is slightly damaged... hoping there'd be a few degrees of difference between the two... and I'm happy to report I can now adjust the plate so the points open as the S mark come into alignment, with some further plate adjustment possible.

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schrader7032
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San Antonio, TX
Joined: 10/27/2006
Posts: 6954
I'm not sure if I'm

I'm not sure if I'm following, but the given gap for the points is not sacred. Nominally on the twins, they call for 0.016" but that can be anywhere from 0.012 to 0.022. The gap (as related to the dwell time) is just not that critical on twins and I suspect singles. On a V-8 engine, the dwell time is very critical to allow the coil a chance to get saturated before the next time it's opened. But for a twin or a single cylinder, the amount of time the points is closed is a very long time, thus allowing plenty of time for current to flow and saturate the coil.

I say change the gap as needed to bring the adjustment range back with the timing. A small change in points gap makes for a very large change in timing.

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'78 R100/7 '69 R69S '52 R25/2

ScottA
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San Diego
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it's a convoluted story

thanks for that information about the points gap.

I noticed the long dwell of the ATU cam and was wondering about the coil's response.

It makes sense what you're saying, that the singles are on the opposite end of the spectrum (from those high-revving multi-cylinder engines where single coil saturation becomes an issue) and that there's consequently greater leeway with the gap setting.

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Airhead77
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Brisbane, Australia
Joined: 07/24/2013
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Thanks!

It seems Scott that we are helping each others with our pictures.

I installed last Saturday the silencer/muffler and started the bike again. Everything was rattling until I realized that the pipe is touching the rider's foot rest with the engine vibrations. I was trying to find a solution until I saw your picture yesterday! I installed the front clamp wrongly: I "sandwiched" the black part that has the hole with the clamp instead of installing it under it like you did. That keeps the pipe at least a centimetre higher and touches the foot rest. Feels stupid now that I think about it.....

I'm in debt a few more beers Smile

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Current: 1972 BMW R50/5
Sold: 1960 BMW R27
Christos @ Brisbane, Australia

ScottA
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San Diego
Joined: 08/09/2007
Posts: 296
happy to be a help

That lower header bracket had me confused too.
Fortunately it had witness marks from previous use, and I’ve been collecting photos of other R27s for a while… so I had plenty of clues.

In fact I wish there were more photos on the web of half disassembled R27s like mine, especially now that I’m laying-in the harness.
The main harness is pretty well in place. I’ve removed the back fender to access the rear swingarm and hope to have the aft harness in the fender tunnel this evening.
(I’d be more inclined to post pics if my workspace was better lit & organized. Wink )

I took a good look at the final drive last night and got the sense that it was professionally rebuilt before I picked up the project… very clean, feeling perfect, fresh grease where the shaft attaches, etc.

On the other hand, the shocks look like they were new 52 years ago.

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'61 R27, '63 R60/2 etc.

ScottA
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San Diego
Joined: 08/09/2007
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hanging the exhaust

today I replaced the silencer's silent-block and checked the fit of the exhaust assembly.

all ready for the part

used these for installaton

finished

but I wasn't able to get a good fit using the reproduction header & silencer.
I want to see the header flange coplanar with the exhaust spigot's face.

This is the best I was able to do today. I'd rather not have the assembly stressed with preload.

There's a copper-asbestos crush washer to improve the seal, yet I'd like to make it better before that.

While there may be several causes, my first guess is the header's final bend is a couple degrees too much.

The long slip-fit with no expansion slots doesn't allow any fudging of the angle.

Shortening the hanger would bring the silencer up, improving the angle at the spigot.

There's room to raise it about 10mm, maybe half of what would be required.

The four motor/trans mounts are new. all seems well otherwise.

Any suggestions for improving the fit?

-Scott

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'61 R27, '63 R60/2 etc.

ScottA
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San Diego
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Posts: 296
Federscheibe für Rundmutter

The long-awaited wave washer arrives from Germany

taking up residence in its new home

This, with a bar in the nose of the clamp, allowed me to provide counter-torque

I took it to 120 Nm, which may be low but seemed sufficient, yes?

Having done that, I was able to do this.

and yes I cleaned the tools and stuff off the floor so I could sit and roll back and forth a few inches. Big Grin

'hope I have time to fit the rear fender this evening.

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'61 R27, '63 R60/2 etc.

ScottA
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San Diego
Joined: 08/09/2007
Posts: 296
title & registration

Still a few details to resolve.

This morning I made a vehicle inspection appointment with the California Highway Patrol, set for a week from Monday.
The DMV wants the bike inspected before taking it back into the system.

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'61 R27, '63 R60/2 etc.

ScottA
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VBMWMO #7638
San Diego
Joined: 08/09/2007
Posts: 296
brakes

Once upon a time the PO had the front shoes relined, but not arced.
There was too much material on the shoes to fit them, assembled, into the drum.

I finally dealt with that his morning...

...and figured it was time to install the hubcaps.

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'61 R27, '63 R60/2 etc.

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