I can't blame this on a higher compression rebuild, because when I purchased this bike (1998 RK), the starter seemed to be dragging, but one's first thought would be to chalk it up to a likely tired battery. The battery tested good with the meter, 12.5+- and 14 +- while running. I did not have it load tested. The battery was three years old and I have a replacement in hand, but have not installed it yet....because my voltage regulator failed the test in the sticky, so I have one on order. It cranks right up cold, but hot.....the starter drags. I stopped for fuel this week and the thing would not start....only click...click...click, like you would get from a weak battery. I was about to call the wife to bring the jumper cables, but after about 5-minutes....it fired right up.

Now...knowing the voltage regulator is suspect (failed the test and has a small voltage present on both leads) I am trying to wrap my brain around what's happening here. The alternator passes ALL test and is good.

Could this be just a starter that is dragging when it gets warm/hot. Not from heavy use....but by riding the bike? I cranked it up, rode some 25-miles to a gas station and when I hit the button....it just acted like a dead battery until it cooled for a few minutes, then fired right off. I have since removed the solenoid plunger and cleaned those surfaces, but I won't know what has done any good until I have replaced the known (by testing) defective regulator.

Any thoughts?

 

Wait until you install the new regulator, then check out the charging system.

Trying to troubleshoot before you have a known good charging system/battery will be like chasing your tail...

Some things you can do now are: clean all the battery cable connections and ground connections (check that ground cable between the starter and the frame), solenoid connections, relay connections, consider replacing the starter relay, they`re cheap).

I would replace the contacts and plunger on the starter solenoid, you can find these parts at any starter repair shop (at a fraction of the dealer price). This is a very common automotive starter.

 

Thanks for the response. Yep....I understand that. I am an electronics engineer by degree and trade (even though retired now). I have performed plenty of tail-chasing exercises.

The pins on my regulator both measure .245 volts. Now...that isn't much and since both pins carry the exact same potential and fit into the stator that is a closed coil....they would cancel-out and do nothing. BUT...according to all the test procedures I read, if those pins have any degree of voltage appearing on the pins....it's defective and that's what I'm going by. I would like to find a schematic of the regulator internals and I can figure out how that's happening. Obviously, leakage in the rectifier circuit. I do not reside close to a dealer, so I have a regulator on order and will test it and then install it before I go any further.

I should know better, but we all are capable of jumping thru our rear-ends and spastically searching for a complicated problem that is not all that complicated. Since I created this thread, I have gone back and removed EVERY bolted-down or screwed on connection and did indeed find some corrosion on the cable-to-starter copper stud.
Different metals expand and contract at different rates. Not trying to get too scientific here, but I can visualize a cold connection (starts right up if it's cool) failing as the connection components heat-up. Copper stud, plated copper cable against a steel base on the starter held in place by a steel nut....which was filled with corrosion that could not be seen. That connection "looked" so clean that I passed it over the first time I cleaned the battery cables.

It makes sense now. When the bike was cool, the connection would "make" and all was well. When hot, the connection would open-up to some degree and increase the resistance in the battery cable to starter connection. Current flow is determined by potential (voltage) divided by the resistance in the circuit (ohms). A cable with .5 ohms of resistance would afford a flow of 24 amps. Just adding 1/2 an ohm (poor connection) would limit the current flow to 12 amps.....that's cutting the starting capacity by 50%.

I may have fixed it already, but sometimes...things can be a blessing in disguise. If indeed I have found a potentially failed/failing regulator....now is the time to replace it. I'll know if I have fixed it when the new VR gets here.