1969 CA77 Condenser

[quidger]

Hey Muddy,

Regarding the spark plug test….. do you put the body of the plug in solid contact with the cylinder or do you try to ground the gap end against the cylinder.
My test light comes on both when the line on the camshaft is pointing directly downward, as your photo indicates, and when the line on the camshaft is pointing directly upward. My test light comes on in both instances exactly when the “F” lines up with the line on the rotor.
Any tips on keeping the points together and avoid having the little parts (insulators, nuts, etc ) shoot across the room after you remove the little nut (I use a 5.5 mm wrench). I spent about an hour on hands and knees with a magnet until I located it.
Thanks

[Muddy]

G'day quidger

For the spark plug test, by far the best thing I have found is to have a short, think jumper wire with an alligator clip on either end. Clamp one alligator clip onto the threaded base of the spark plug and the other onto the motor or frame of the bike. An alternative is to try and hold the threaded base of the spark plug securely against the motor (this can be done, but is a bit harder). Whatever you do, you want to ensure the spark plug is electrically well-grounded back to the motor or frame.

Yes, that could be the case with the points and the mark on the cam shaft, I'm just not sure I recall - it is a while since I've done this. The key is to make sure the points gap is correct and the timing of them opening is correct. Ed Moore's info suggests the points opening when the mark is pointing up is normal.

A tip for the points springs is to use a very small pair of vise-grips to clamp them in place. Alternatives are to put another nut/washer on a longer points screw. Insert the square terminal between the 2 nuts - saves undoing the main points screw nut every time. Another alternative is to slot the square condenser terminal so it becomes a u-shape and can be inserted without having to remove the points screw nut.

Good luck - you are nearly there!

[quidger]

Good stuff, Mate.
The voice of experience!
I’ll report back as soon as I take the next steps.
Thank you.

[quidger]

Figured out one of the two new plugs i bought was bad. Replaced with one of the older one and the bike started right up.
The bad news is the original symptom that I am trying to remedy is still the issue. I guess we can rule out the condenser since the CL77 was wired for this start up.
The problem is that the bike runs for about 5 minutes and then slowly loses its idle and dies. When I sensed the bike was losing rpm’s , I turned the idle speed screw in about one turn and there was no noticeable increase in idle speed.
Frustrating, but at least it started.
Do you have any further thoughts ?
Here’s a video link of the bike running and dying after today’s start up.

https://www.dropbox.com/scl/fi/flaf65p2 ... afjbd&dl=0


Thanks.

[Muddy]

Well done quidger. It is nice to know that the old girl at least starts now.

Yes, I think you can rule out the condenser as being the fault now. I have a feeling that the problem might be fuel/carby related.

Check the voltage at the battery when you start the bike and continuously until it stalls. I don’t think this is the issue, but it is important to check and confirm it is OK.

You may know that the Dreams had 3 different carburettors fitted. There are two styles of Keihin carburettors on the 305s and one Mikuni, but the Mikuni is rarely fitted. For the Keihin that you most likely have, there are the “round bowl” carburettors with floats with rounded sides and the “square bowl” carburettors have flat-sided floats, with matching float bowls and bowl gaskets.

I’m not sure if you replaced any jets or needles when the carb was cleaned, but be very wary if you did. There are several sellers of carb kits that have the incorrect sized jets and parts in the kits they sell.

As Bill Silver says, “If the bike starts with NO CHOKE, it has a problem!”

It is always very hard to diagnose problems remotely, but here are a couple of things to try (courtesy of Bill Silver and others):

Make sure the carburettor mounting flange is not excessively warped. Almost all used carburettor bodies will have warped mounting flanges – make sure it is not excessive. A large flat file will flatten the flange area out if needed and used carefully. If a new O-ring is installed, the carburettor mounting nuts must be just lightly tightened, otherwise more bending of the flanges will occur.

Check carb floats for any pinholes, to prevent “sinking” once the float chamber is full.

Check that the carb float height is set accurately and correctly – 26.5 mm for Keihin carbs.

Ensure the carb slide needle is set at the correct height. Remove the jet needle from carb slide and install the clip on third notch from the bottom (of 5 notches). Make certain that the clip and needle are securely fastened in the slide before re-installation.

Check that the carb slide is orientated in the carb correctly and that it slides up and down freely.

Clearly identify the carb idle mixture screw and carb idle speed screw – these are different and it is essential to know which is which.

Turn idle mixture screw in lightly to the stop. Open it back out about 3/4 to 1 1/4 turns.

Turn the idle speed screw in until it just begins to raise the slide, then add about one-eighth to one quarter more turns in to give the engine an opportunity to fast idle initially.

With these settings the engine should start, but will need choke. If it does not need choke, there is probably some setting/s incorrect.

Once the engine is warm and idling with no choke, check the ignition timing with a dynamic timing light. Ensure it fires on the “F” mark at idle. Check to ensure the spark timing does not advance further than the 2 firing marks on the rotor as revs are increased above around 2,500 rpm.

Check throttle response. If there is a hesitation or “spit back”, when the throttle is opened, turn in mixture screw (air screw) 1/8 turn at a time, until response improves.

At all times and for all adjustments, record the original position, the new position and the observed changes in performance. Never adjust more then one setting at a time, before observing results.

Good luck.

[quidger]

Hey Muddy,
Well, even though my Dream issue is not completely resolved, it’s nice to have the problem isolated to one area. I’ll concentrate on the details of the carburetor until I get it running properly.
My sincere thanks to you for all of the time you invested and the advice and knowledge you shared. I learned a lot.
I’ll let you know when I get the old girl running well.

Regards

[Muddy]

Good luck with it quidger.