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FL54
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1963 R50 new to me. I installed a new coil from Benchmark and decided to re time the old girl. I discovered that I have an updated magneto body and points. When I set the points to specs, the timing is significantly retarded (past OT mark.) The point gap is adjusted by way of a spring loaded screw but the points base is not adjustable. The only way to get the points to open at the S mark is to open the points over .0025 or change the magneto timing neither one a good solution. The bike seems to run OK, still a little hard to start hot but I would rather be within specs. Anyone have any suggestions? Thanks in advance.

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Beemer100
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FL54 ... does this indicate

FL54 ... does this indicate that you are otherwise running a 54 Pan?

I would recommend that you take out the advance mechanism and restore it first. I think there are some springs missing. Check on the web for BMW advance mechanism and you will find some pictures how the springs should look like to work correctly.
Once the advance mechanism is off, please make a picture of the points etc and also the magneto so that we can help further. Do you have a manual?

cheers
Klaus

FL54
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Thanks Krause for reply. I

Thanks Krause for reply. I actually have a '48 Panhead but I was born in '54 so that's my user name that I use an a couple of Harley forums. At my age I have to keep things simple.
Thanks for noticing the broken spring on the advance unit. It must have just happened because it wasn't broken the other day when I had it off. Here is a picture of the points. I'm not overly pleased with the set up as you have to remove the condenser wire in order to get the feeler gauge in.

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Beemer100
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48 Pan ... niiiice. I got a

48 Pan ... niiiice. I got a 47 Knuck and a 57 Pan ... so a bit of both!

Have your advance mechanism checked by someone who knows these things. If these beasts don't work properly you will have problems to get your bike running properly.
I never saw this aftermarket plate which holds the points and the condenser. Maybe someone else here on the forum knows how to work these. Don't really see if your magneto is timed properly (notches aligned at S mark)
For the condenser, I would change it anyways if I don't know how old it is (get one with a longer cable Wink

cheers
Klaus

Beemer100
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check out here. You see a

check out here. You see a couple of pictures of a good adv mechanism

https://www.ebay.de/itm/BMW-R51-3-R50-R60-R69S-Fliehkraftregler-original...

hope that helps

FL54
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Thanks again Klaus. The

Thanks again Klaus. The advance mechanism works OK one of the spring ends just broke. I'll order a pair today and another condenser. Just wondering if the stock points would work on this aftermarket plate.
A knucklehead is on my bucket list but they have gotten soooo expensive. I've picked up a few generator shovels and they have appreciated significantly since acquired. Just a commentary on the purchasing power of our currency.

schrader7032
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That appears to be the

That appears to be the Pentacomm plate, which is an aftermarket setup for setting points. My understanding is that you actually set the points gap with the engine running by using an allen wrench. Search for that type of plate and learn more about it.

I wouldn't be too continued about the points gap being somewhat different than the 0.016" called for...the gap is more critical for a 4/6/8 cylinder engine, but with a 2 cylinder engine, the points will be closed long enough to get the coils "charged up".

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Kurt in S.A.
'78 R100/7 '69 R69S '52 R25/2

schrader7032
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That appears to be the

That appears to be the Pentacomm plate, which is an aftermarket setup for setting points. My understanding is that you actually set the points gap with the engine running by using an allen wrench. Search for that type of plate and learn more about it.

I wouldn't be too continued about the points gap being somewhat different than the 0.016" called for...the gap is more critical for a 4/6/8 cylinder engine, but with a 2 cylinder engine, the points will be closed long enough to get the coils "charged up".

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Kurt in S.A.
'78 R100/7 '69 R69S '52 R25/2

FL54
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Thanks Kurt. That's the one.

Thanks Kurt. That's the one. Apparently, once I get my advance mechanism fixed, I can use a timing light hooked up to a 12v battery and adjust the timing while the bike is running. In a way, that's easier than static timing her.

kfelt
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Points Plate

schrader7032 wrote:

That appears to be the Pentacomm plate, which is an aftermarket setup for setting points. My understanding is that you actually set the points gap with the engine running by using an allen wrench. Search for that type of plate and learn more about it.

I wouldn't be too continued about the points gap being somewhat different than the 0.016" called for...the gap is more critical for a 4/6/8 cylinder engine, but with a 2 cylinder engine, the points will be closed long enough to get the coils "charged up".

I have one of those plates on '56. Works well, easy to adjust points by turning screw. Like a Chevy.

Daves79x
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But

Pentacom points plate or not, the fact remains that many pattern points sets are not made correctly and will not be close to correct timing at the specified gap. Vech sells good ones and the timing will come in pretty close at the correct gap. As Kurt said, the bike will run fine though at a much greater or lesser gap than spec. It just doesn't sit that well with me. Start will a good set of points and the mag timed correctly and you'll be fine.

Dave

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wa1nca
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Penacom Points Plate

Quote:
Just wondering if the stock points would work on this aftermarket plate

The pentacom system uses a set of points made for a chevy
The gap is altered to set the timing to specs
It will never be same as bmw spec .016

Once the timing is set then one can measure the gap and use that for a reference to readjust the points as they where
When the gap is set back to what was measured then the timing would then be good

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Tommy Byrnes
54 R51/3 55 R50 64 R27 68 R69US 68 Sears Allstate 250 (Puch)

FL54
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Thanks to everyone for

Thanks to everyone for responses. I've ordered some new springs from Benchmark to replace the broken one on my advance. When I get that done, I'll time the bike with a light. I think the Indy did that and when I checked the point gap it was over .0023. I'll post results at that time.

FL54
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Just wanted to circle back on

Just wanted to circle back on this thread and report results. Not only was one spring on the advance mechanism broken, the other spring was the wrong length. One side takes a 8mm spring and the other is 11mm. The PO had both sides 8mm. I replaced the springs with the correct ones and timed the bike with a timing light. Turns out that I wasn't too far off the mark timing it with a continuity tester. What I did find however,was that even though I had the safety gap for the coil set at 10mm, a spark would occasionally jump the gap. I have a new coil, plugs, wires and caps. What would cause the spark to jump across the 10mm gap when the plug gap is .028? Thanks in advance.

schrader7032
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Without looking back on the

Without looking back on the thread, what spark plugs and plug caps are you using? Sounds like there's too much resistance in the usual path to the spark plugs, thus resulting in the ignition system taking the "easy way" out.

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Kurt in S.A.
'78 R100/7 '69 R69S '52 R25/2

FL54
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Thanks Kurt for reply. NGK

Thanks Kurt for reply. NGK B8HS plugs and caps.

wa1nca
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Spark plug gap

The Barrington manual states the plug gap should be .025 not .028

Tommy

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54 R51/3 55 R50 64 R27 68 R69US 68 Sears Allstate 250 (Puch)

FL54
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The owners manual states .028

The owners manual states .028 on the plug gap but the the spark should jump either plug gap as opposed to the 10-11mm safety gap, correct?

schrader7032
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I would say that 0.026" is

I would say that 0.026" is more of a general standard for these bikes. Jeff Dean's online manual does show 0.028" but that seems a bit wide. Note that the greater the gap, the more energy it takes to jump the gap. If that's the situation, that could explain why the system jumps the safety gap. Also, when the cylinder is in the compression stroke, that also increases the resistance for the spark to jump the gap. Definitely reduce the spark plug gap to either 0.025 or 0.026.

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Kurt in S.A.
'78 R100/7 '69 R69S '52 R25/2

FL54
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Set gap @.025. Still getting

Set gap @.025. Still getting an occasional spark across the safety gap. Is there any situation where the spark should jump the gap on a properly running engine? It's only on the left cylinder.

wa1nca
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Plug wire and caps

caps and wire should be zero resistance spec's

Tommy

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54 R51/3 55 R50 64 R27 68 R69US 68 Sears Allstate 250 (Puch)

schrader7032
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How sure are you of the

How sure are you of the 10-11mm safety gap? I found it sort of hard to measure. I think I ended up finding say a wrench or something and measured the thickness of the working end of the wrench. Once I found one in the 10-11mm range, I could use that as a slip fit to get the gap correct.

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Kurt in S.A.
'78 R100/7 '69 R69S '52 R25/2

FL54
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Thanks Kurt and Tommy for

Thanks Kurt and Tommy for replies. I use a 10mm Alan head wrench, lay the flat on the point and slide the wire down on the opposing flat and tighten.

FL54
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Checked resistance in wire

Checked resistance in wire and cap 0. On a hunch, I went to the auto parts store and picked up some new plugs and voila, problem solved. Plug in question has less than 100 miles on it.
Thanks for the help on this.

schrader7032
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Nice job! Enjoy the ride!!

Nice job! Enjoy the ride!!

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Kurt in S.A.
'78 R100/7 '69 R69S '52 R25/2

FL54
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Thanks Kurt. Appreciate the

Thanks Kurt. Appreciate the help.

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