Bob Dale wrote:Without further fueling the fire I will try to respond completely objectively...
1) The red herring was in reference to the diagnosis that, by the photo evidence and the performance symptoms, I had reassembled the top end with the cam sprocket one tooth off from top dead center. In reaction to that diagnosis I had questioned the opinion and was assured that this was the only possible outcome so I pulled the engine and dissassembled it. The cam sprocket was in fact correct.
2) Does it work? I cant answer for sure if it works or not. I have only installed the motor and started it but there seems to be a marked improvement. I hesitate to call it a success because I worry about possible side effects that could damage the engine. I have also not fully reassembled the bike to ride it yet so I dont know if it works correctly under load. This course of action (modifying the points plate) was warned against by LM but after an extended period of no contact from him, and upon discovery that the cam sprocket was set correctly, I felt like his warning might apply more under circumstances that did not exist. In other words, I can completely see how modifying the points should not be considered a correction for a one tooth off assembly. With that ruled out, the new goal was simply to get the spark to fire at the correct time, which this modification seems to achieve. Why would this be necessary? It shouldnt unless maybe the points plate, as suggested by another member, is not the correct one for this motor. I didnt buy this bike new and have no idea what previous owners might have done to it. Right or wrong, that was the premise.
3) Best option? Maybe LM will take this one. He has indicated in a PM that there is a correct way to have dealt with this but has not elaborated on what it might be.
Houston 1966 305 Dream Log
Hello Bob. The message above this last one you sent may answer what I recommend at this time. When I saw the 3 pics I recalled that another feller had the same problem you have and above is what I recommended and it worked. Give it a try?. ..................lm
Re: TO BOB DALE AND ALL OTHERSOnce again the timing of our messages seems to be missing each other a little bit. While my response to MS appears after yours, it was submitted prior to your posting. We were probably typing them at the same time. Either way, appology accepted and as always, your advice is appreciated. I will try your procedure below and see what happens. I can tell you that I have already reduced the points gap to well under the .35 recommended in the Bill Silver CD and dont have much more gap to close but I will try it. I guess the other item of interest would be "is there any remaining concern with burning up my pistons if the points plate does in fact need to be rotated past its normal limit?"
I am pretty sure that I understand exactly what you are saying to do and I just tried it. I know that what you are saying is correct but unless I am totally misunderstanding, it is physically impossible on my engine. The attached photo shows the points cam at top dead center...slightly past the F mark. At this position, the points "lever", for lack of a better word, is just entering the range of the shaft that would be causing it to open. Therefore, it has already been closed for quite a while at this point. In order to catch it approaching its closing position, which would send the spark as it reaches F, it would have to rotate approximately 90 degrees to a position that just follows the apex of the shaft as it rotates clockwise. It currently precedes the apex. This picture is an old one that still shows the points plate rotated as far clockwise as it will go but I have also tried it in several other positions, including centered as you instructed and fully rotated into the new channels that I opened. A suggestion that I just read in response to my posting under "Motors" indicates that another 305 owner had success by filing down the "follower" (lever?) but I dont see that improving this situation either. Is it possible that this is just the completely wrong points plate for this bike and it is therefore oriented so far off that it wont work? The 2nd picture shows a points plate currently listed on ebay for a 305 that is COMPLETELY different than mine. I cant tell for sure how it mounts but is this a better part for my engine? Another clue to support this theory is that this photo appears to show a metal follower lever and my cam has slight scratches that I dont think would have been caused by the bakelite type lever on the current points. None of this is really making any sense at this point but what I do know is that its still not running correctly. Sometimes the simplest solution is all thats left.
We may be near the answer. The coil fires when the points OPEN not as they CLOSE. So please try as I last suggested. Move plate to center. Put continuity lamp to wire on points. Turn key on. Rotate rotor to "F" and then open/close the points so the light Comes On at "F" and tighten points to plate. I don't know what that other points plate is for but for sure not any 305 I've ever seen. Your plate is correct for a DREAM engine. ....................lm
Also, I must not be using my meter correctly since I was checking for completion of the circuit, not opening. My test light is burnt out so I have been using a voltage/continuity meter but obviously not connecting it to the right places. Where should each lead be attached...one side to the points and the other to?
One side to the wire at the points and the other to anywhere on the engine cases. .................lm
|