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1963 R69s Knocks

166926

New member
Hi all, just picked up a 1963 R69s, dover white, the one IÔÇÖve been looking for all my life. Fully restored, and less than 3 miles from my house. Even sold my R50/2 to pay for it.

Im afraid Im paying for it now

Runs fine, but in 4th it develops a knock about 50% of the time. IÔÇÖm not going nuts speed wise, about 60 or so. I can get that knock in 3rd sometimes, and it seems to happen more under load. I can sometimes get it at idle. I was able to videotape it in idle in case anyone wants to listen.

I can feel that knock, and I noticed that when I killed the motor at a stop (the idle needs to be upped), after a session of the knock, it had barfed up some oil out of the oil fill and the breather tube.

The motor seems to run fine, the clutch seems to be fine, but IÔÇÖm afraid of what it could be.

The only thing I can think of is that I should probably adjust the valves, but it isnÔÇÖt a ÔÇ£tappetyÔÇØ kind of noise.

On top of all this, I was wiping the oil off, and then found a tiny bearing, clean as a whistle, on the shift lever, just stuck there (like magnetically). Looked about the size of the bearing on the clutch throwout bearing that has about 6 bearings in that little disc-shaped retainer. But I canÔÇÖt say IÔÇÖve had a problem with the clutch.

To boot, itÔÇÖs a bear to start with the kickstart, particularly when itÔÇÖs hot. IÔÇÖve got to 2x check the magneto per VechÔÇÖs article, but I also see that it has the ÔÇ£modernÔÇØ plug caps, and not the brown ones.

Can anyone talk me of the ledge here?
 
I can't talk you down...but you don't need to jump off the ledge. These things are repairable.

What you're hearing is probably a conrod or main bearing knock. The bearing(s) failed because an oil singer filled up with crud - that's its job - and it wasn't R&Rd soon enough. The clogged slinger impaired oil circulation and starved one of the bearings. DarrylRi has a good presentation here: http://darryl.crafty-fox.com/motorcycles/slingers.htm

If this diagnosis is correct, the "restoration" was either incomplete, or it was done after the bearing(s) had been damaged and the damage was not discovered and rectified.
 
I did the slingers on my r50/2, and I have to say it was a pain in the rear. Since these have the roller bearings on the crank, replacing the bearings is a job for a specialist.

I was assured that the slingers were cleaned, and if I recall, the crank may have been rebuilt. This bike is beautiful, and I can't imagine that these weren't addressed.

I know it can be fixed, but I was hoping for the "adjust the valves and replace the spark caps" answer...

I'll check the link you sent, and I'll either be crying or still scratching my head.

Jon
 
Jon -

Any chance that the knock is pinging? With the high compression engine and if the timing is miss adjusted or if the advance mechanism is not working, you can get too advanced and cause pinging. I'd be glad to listen/watch the video if you want to send me a copy.

The R69S does slap the piston skirt a bit, due to the offset wrist pin...but that's usually just when cold.

Try to get a picture of the bearing and post it.

Sure go ahead and ensure that the valves are set right and see if that makes a difference.

Hard starting when hot can be the symptoms of a couple of things:

- magneto not set right. Note that the ignition and magneto timing are set independently of each other. Vech should discuss it correctly, but most literature say to move the magneto housing to help with the ignition timing....wrong...don't do that.

- your hot engine start routine might need to be different than your cold engine start routine. I had this problem, and thinking it was the magneto coil, bought a solid-state one. Didn't fix my problem. A buddy had to help me figure out that my engine tends to flood easily making it hard to start hot. I had to hold the throttle open wide, kick through a few times to clear it, then start with one kick, hand off the throttle. Works great.

- could be the magneto coil getting old. The coil is supposed to be a continuous coil of wire. But when it ages and it breaks into smaller sections, the gaps in the sections open when hot. Now you don't have the same number of windings and get less power when kick starting. When cold, the gaps close up a bit.
 
Also, use your timing light to check your advance. If it goes beyond the F mark at high RPM the engine can knock. If that is the case there is a simple fix (if you've the "new" style advance)...

p-20081230-1125-4830-Version-2.jpg


The screw holding the leaf-style advance spring was changed to one that is longer. It is adjusted to provide a hard stop to the advance. Trial and error will get the advance to stop at the F mark at high RPM.
 
marchyman brings up a good point. He shows what has been called the "Caro Stop Screw" suggested by a guy by that name. It can only be used on the later style advance units. Note the shape of the leaf spring. If your advance unit has a spring like this (take from Duane's site), then you really should find a later one because the earlier unit leaf spring was known to break, resulting in an over-advanced situation.

advance1.JPG
 
Runs fine, but in 4th it develops a knock about 50% of the time. IÔÇÖm not going nuts speed wise, about 60 or so. I can get that knock in 3rd sometimes, and it seems to happen more under load. I can sometimes get it at idle.

I can feel that knock,
To boot, itÔÇÖs a bear to start with the kickstart, particularly when itÔÇÖs hot. IÔÇÖve got to 2x check the magneto per VechÔÇÖs article, but I also see that it has the ÔÇ£modernÔÇØ plug caps, and not the brown ones.


If you can feel the "knock" in the foot pegs, and hear it, under load, the engine probably has a bad rod. Sorry to say that. But feeling it in the foot pegs is a bad sign.

Other causes of a "knock" that R69S's are prone to do, is if there is piston slap.
Excessive clearance of the piston to the cylinder will produce an audible noise under acceleration.

And, yet another cause of a loud "knock" can be a spun wrist pin bushing. All of the pre 1970 bikes will do this if the wrist pin bushing spins in the end of the rod.

In short, I'm afraid the engine needs to be torn down and examined.

Sorry.

Let me know if you want help with this. We do this work every day.


Vech.
 
marchyman brings up a good point. He shows what has been called the "Caro Stop Screw" suggested by a guy by that name. It can only be used on the later style advance units. Note the shape of the leaf spring. If your advance unit has a spring like this (take from Duane's site), then you really should find a later one because the earlier unit leaf spring was known to break, resulting in an over-advanced situation.

advance1.JPG

I have found a way to limit the advance on an old style advance unit as well.

2010-09-27%252000.14.21.jpg
 
That sucks

I don't have any advice. I just want to say "That Sucks." I have been in your shoes and I hate what you are going through. Hang in there...
 
What about the ball bearing on the shifter????........Golly if it got by the seal at the shifter wouldn't xmssion oil be leaking or weeping?????.........God bless......Dennis
 
Just an update. Been busy, Vintage Motorcycle Days and then family vacation, but I spent a little time in the garage today, checking the timing, etc.

1. Looks like the magneto set up was spot on, per Vech's article.

2. I then undid the wires to the points. Wire from the condenser simply fell off from the top of teh condenser. I'm wondering if a bad connection between the condensor and the points could have anything to do with this? I went out, per Vech, and got a Ford condenser.

3. I then spent an inordinate amount of time adjusting point gap. When all is said and done, I undid the advance bolt, slid it out, and set the gap to .015" at the highest point. I then bolted the advance unit back on, with the index lined up with the cut on the camshaft.

4. I then statically timed it, which was a bear, but not as bad as it coudl have been (I had worse times with my r50/2, but I guess I'm getting better at it).

5. I then wired it all back up, and got it started. Seemed to run ok, but this bike is a bear to start; can't really say if it was easier now or not.

6. I ordered new non-resistor caps from Vech, and I expect them shortly. I hope that makes startup easier!

7. Vech, you are scaring the crap out of me with the rod knock. I'm going to fool myself for the time being, and assume it's a timing issue.

Once I get the new caps, I'll check the timing with a strobe, and report back.

Is there a good shipping company if I want to send this off to Vech?
 
R69S rebuild?

7. Vech, you are scaring the crap out of me with the rod knock. I'm going to fool myself for the time being, and assume it's a timing issue.


Sorry, I don't mean to, but it is a possibility. You know, like I tell everyone, if I had X ray vision, I'd be looking at women, rather than old BMW's. Unless you have documents of previous work done, there is simply no 100 % way to be sure, other than take it apart and examine and measure everything. From the crank outwards.


Once I get the new caps, I'll check the timing with a strobe, and report back.

Is there a good shipping company if I want to send this off to Vech?

We have crates already made to hold the bottom end of the engines, less the heads and cyls. Call Bench Mark Works and ask for me. I'll be happy to tell you everything you could be facing...
 
Update part two

Update part two:

I got the proper zero resistance spark plug caps from Vech, and you can tell it makes a difference in the starting. It's still a bear, but now I think that I have a different problem.

I got it running, ran it for a while, got the engine nice and hot, revved up and down, doesn't seem to have that "pinging". I think with everyone's help, it may be sorted. I saw the advance arms open and close, so I think we're in good shape.

My big issue now is that it's still a monster to start, and it won't idle; just dies out. I think this may be a two part problem.

As far as the starting goes, I found another article by Vech about his starting procedure, so I'll give it a try; as it turns out, just before I got it started, I pulled the plugs, and they were wet with gas, I dried them (one seemed to have some carbon-like flakes on it), put them back in, and success!

Once started, however, anything less than approximately 1/4 throttle means the motor dies. No idle at all, and trying to start again means more agony.

I can't believe how out of shape I am, my leg hurts from all the kicking!

I'm going to pull the idle jets, to see what's what there.

Also, one last thing, but the coil is a replacement, and is marked "emerald island". I have it in my head that these were the coils that were known for being a bit dodgy. Was this the case?

Thanks to all for your input - probably a boring thread, in the grand scheme of things, but once I figure out how to post some pictures, and you can see just how pretty this bike is, you'll know my hearache at not having a reliable or operational ride.
 
Glad your making progress...though maybe sideways!

As for the idle, I'd recheck your valve clearance. Poor idle typically means the valve clearance is gone and the valves don't completely close at all during a complete series of strokes.

Also, if not done already, you should consider a carb overhaul. You could have some varnish or small debris stuck in a passageway. The carbs are not overly complicated.

As for the coil, the Emerald Isle coil is the solid state replacement and should be rock solid...much better than the old failing originals. Taiwanese made I believe. IIRC, there were two versions of this. A second ground wire was added to the redesigned one...these were better. I'm not sure if the additional ground wire prevented coil failure or if it made for better running...it certainly made them more reliable. I bought mine through Vech...if he pops on this thread, he can provide some background.
 
Idle jets

Or slow speed jets are usually what causes these bikes to act like that. I cleaned the ones in Ole Grey a bunch of times until I found a source for None-Ethanol gas.
Although they tell you not to I found the most effective way to clean the idle jets is to take a single strand of stainless brake cable and run it through the passage, a simple shot of carb cleaner in the carb body passage works for them.
 
Me too

Or slow speed jets are usually what causes these bikes to act like that. I cleaned the ones in Ole Grey a bunch of times until I found a source for None-Ethanol gas.
Although they tell you not to I found the most effective way to clean the idle jets is to take a single strand of stainless brake cable and run it through the passage, a simple shot of carb cleaner in the carb body passage works for them.

I did the same thing with my R69S carbs. After experiencing it for the first time, I made sure I ran Lucas gas treatment in the tank.


I also had the pinging issue and my problem was because the manual timing advance lever had worked itself loose and was allowing the timing to move at will.


Those are great bikes. I was lucky to have Clanton Austell to help me out. I am glad you have found someone who is good with these bikes. BTW, mine had over 300,000 miles on it when I sold it and it was still a strong runner.
 
R69S koccks - coil?

Also, one last thing, but the coil is a replacement, and is marked "emerald island". I have it in my head that these were the coils that were known for being a bit dodgy. Was this the case?

The reproduction coils we sell have been very reliable. As with anything made by humans, there is a bad apple now and then. If you are questioning the condition of the coil, send it back to me, we'll test it.


Vech
Bench Mark Works.
 
Success!*

I removed the idle jets, and sure enough, couldn't see through them. Carb cleaner and some air did the trick, shot a bit of air through the carb, and just to be on the safe side, I cleaned out the main jets as well (they were fine).

Put it all back together, and 2-3 kicks later, success!

I used Vech's starting technique, no tickles at all, and it looks like we have a winner!

The asterisk, however, is becase a. I can't find the damn timing hole plug, and b. I haven't had it on the road for a full-on test. We have the Woodward Dream cruise a few miles away, but I learned my lesson about motorcycles in a car parade - you are a sitting target as you sit in a traffic jam with a left hand cramp, so I'm going to have to head AWAY from the parade....

I'll see if I can get a ride in.

Thanks to everyone for the help!:wave
 
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