I was feeling pretty good about current bike on my lift. I rebuilt forks, cleaned and repacked steering head bearing, rebuilt front calipers, new stainless brake lines, touched up frame. Bead blasted and painted exhaust and mufflers (R65LS with black exhaust), rebuilt both carbs, replaced push rod seals. Changed every fluid I could find. Had ridden after front end work and the quiver I had at speed was gone. Either the forks of steering head bearing. Last thing, last thing I was going to do before taking it off the lift, riding and balancing carbs was check timing (valves done with push rod seal job). Tiny bit retarded. I disconnected ground wire, removed front cover, loosened and rotated [the points plate a] small increment. Went to start it for dynamic timing. No start. Headlight and tail light on. No instrument lights or starter. Checked kill switch, checked fuses. Engine should run without cover on for timing, right? Pulled ground cable again and put front cover back on. Same picture no start. Stared at the schematic for a while and decided to close up for the night as I was frustrated.
Somewhere in the back of my brain is the thought I have heard this situation before and should know the answer.
Thoughts?
Answers?
Diagnostic plans?
Tim
Thought I would add that I have not had the tank off or done any electrical work since riding it for 2 days to evaluate front end work.
Thanks again,
Tim
Sorry, tank not talk
Hi Tim, I'm a new owner of an 80 R65 and just now (November '19) saw your post which got me thinking. Since you disconnected the ground wire prior to removing front cover. it doesn't seem likely you damaged any diodes or anything else up front. I'm no expert, so just offering up what I do know: I believe the start relay can be damaged by a battery with too low a voltage. That seems to me to be a likely common denominator based on your symptoms. Did you ever figure it out?
Hi Tim, I'm a new owner of an 80 R65 and just now (November '19) saw your post which got me thinking. Since you disconnected the ground wire prior to removing front cover. it doesn't seem likely you damaged any diodes or anything else up front. I'm no expert, so just offering up what I do know: I believe the start relay can be damaged by a battery with too low a voltage. That seems to me to be a likely common denominator based on your symptoms. Did you ever figure it out?
Tim -
You are correct. The bike should crank and run with the engine's front cover removed. Some new thoughts...
Don't forget the safety interlocks...
• Kill switch must be in ON position*
• Gearbox must be in the Neutral position
• Sometimes when the Neutral interlock fails, the clutch must be pulled in regardless of gear position
• Some more modern bikes need the side stand raised (don't think this applies to your 1980 model, but...)
* I'm aware you mentioned this as being on your check list, but my dash lights go dark when my Kill switch is in the wrong position, so there may be a correlation.
As you work on this issue keep in mind that your ignition system is OK (which you can prove by manually opening and closing the points with a screw driver and watching the spark plugs). Your problem lies in the electric starter system. Although wrapped up in the same electrical harness, they are totally and completely 2 different electrical systems. Don't forget that.
The safety interlocks for the ignition system consist solely of the handlebar kill switch. However, the safety interlocks for the electric starter are far more complicated (as the list above indicates), and range all over the bike. Since complexity brings more places and more reasons for failure, it stands to reason that using an Ohm meter to check out the various Switches involved in the starter interlock system is the place to start. After the Switches check out, then move to the Connection to the switches. Connectors are always high on the failure list.
Hope this helps.
Owning an old Airhead is easy.
Keeping an old Airhead running great is the true test.
Thanks for the responses. Mufflerbearing, fixed, But so long ago I can't evan remember what it was.
Tim
Glad it's fixed. Out of curiosity, does your bike have the "EGR" tubing removed (I think bmw calls it pulse air injection)? I'm getting ready to remove mine and trying to find how it affects performance after the change. Thanks.
Let's move the discussion of "EGR Removal vs Performance" off to a new thread please. Others may wish to find this second topic in the future, and that won't happen without the proper subject line.
Thanks.
Owning an old Airhead is easy.
Keeping an old Airhead running great is the true test.
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