The New And Improved Unofficial R65 Forum V2
Technical Discussion => BMW Technical Q&A, Primarily R65 => Topic started by: farmer on May 12, 2008, 11:48:00 AM
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I picked my 79 R65 up last fall with 43k on the clock. I am 3rd owner. Over the winter new clutch installed, main oil seal replaced, complete tuneup/valves adjusted, all fluids changed and spline lube. Runs great now - just had it out for longest ride so far (about 100 miles). The only issue I have now is that bike is hard to start when the engine is warm. Does not matter if choke is on or off. I have to crank the starter for a while and it will finally start. Starts right up with choke on when its cold. It was like this when I bought it - all the maintenance so far has not eliminated the warm start problem.
Has anyone had this issue? Any ideas on what I should check out first would be greatly appreciated. My first inclination is that its a carb issue. Have not done much to carbs (just adj, sync,etc.) I don't know the history of the carbs (no idea if original or rebuilt)?
Thanks
Jim - Cadillac, Michigan
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Sounds like it could be an ignition problem - check the coils for cracks (although that is often a damp weather problem) and make sure there is good contact between the ignition control unit and the mount which acts as a heat sink (use radio shack heat sink compound).
On the old /2s this symptom meant internal shorts in the magneto coil.
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Thanks a bunch - I will take a look at coils tonight.
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Sounds like it could be an ignition problem - check the coils for cracks (although that is often a damp weather problem) and make sure there is good contact between the ignition control unit and the mount which acts as a heat sink (use radio shack heat sink compound).
On the old /2s this symptom meant internal shorts in the magneto coil.
cad jim, your bike originally (and probably still has) a points ignition system. Most of drewboid's comments are regarding the models after 1980 that have electronic ignition.
The coils on your bike were not prone to cracking like the later ones.
You do not have an ignition control unit, so you don't need any heat sink paste.
I am not much of an expert at troubleshooting, but I would take a good look at your points, and possibly the condenser (you can't do much with that, except replace it). Make sure your timing is correct.
To give yourself a baseline, replace (http://suraklyn.com/yabb/YaBB.pl?num=1191053968/9#9) your spark plugs, caps, and wires. If your coils are original (black, with a yellow Bosch sticker on them), you might consider replacing them just because they are getting pretty old. While you are there, check out the front coil mount (http://suraklyn.com/yabb/YaBB.pl?num=1198915890/0#0). This WILL BREAK at some point in the bike's life, taking the MAIN GROUND wire with it.
Some people have reported the rear mount breaking, as well, but mine is still holding.
I once had a /2 that would start right up when cold, but never when hot. This was pre-internet, and I didn't know much (and neither, aparently did my dealer...). I later found out that a bad coil would cause these symptoms.
Granted, a /2 is a TOTALLY different animal, but the basics are the same.
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It certainly could be the condensor - they can be temperature finicky sometimes just before they fail completely.
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Correct, my 79 has a points ignition system.
Appreciate all the tips. I pulled the gas tank last night and did a visual inspection of the coils. Coils look ok (no cracks, etc) and they look original (black and each has 0221100028 stamped on the back end of coil) Is this the BMW part number? Front and rear coil mounts look ok.
Looks like a process of elimination is in order in the sequence: check points, replace condensor, replace plugs, replace caps/wires, replace coils checking to see if starting problem goes away after each change.
I'm betting that its the coils if they are original (29 yrs old).
Jim
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lucky you :'(
I can't control mine! ;D
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Update:
Points, plugs, condensor, spark plug wires checked out ok. So I figured it had to be the original coils. Bit the bullet and purchased a new set from Capital Cycle. Problem solved - starts everytime engine warm or cold! I now can use this bike for my daily commuting (previously could not as I was unsure if it would start). ;D ;D ;D
Thanks again for the tips.