Oldtimershow- starting issues

Hi guys
Last weekend I went to the "Oldtimer im Walzwerk" oldtimer-rally here in Switzerland to see what people still have in their garage. Amazing. For pictures see:  www.ovw.ch/oldtimer-im-walzwerk2023  
On of the pics even my old lady is pictured.
Anyway, though it was awfully hot (above 30°C) I enjoyed the coming and going until I tried to go home. Pressed the button an and heard only that up up noise. Found two nice blokes hat pushed my (not easy with tons of people in front of you) and home I went. So far, so good. 

Yesterday I checked the battery (HAWKER PC 680) and it had 12.53. Looks ok, started smoothly. At very low rpm no charging (consider that normal), slighty increased throttle and chargind went to 14-14.4 V. All ok.
Started several times to see if any changes, yet the battery stayed at around 12.4V.

Looks all ok to me, this night I charged it until full. 

Any recommendations (if not just enjoy the pics)

Holger

Not sure that I understand the phrase "that up up noise" but if it's the sound of the starter relay clicking and nothing happening then I would suggest it's time to remove the starter and clean/ inspect it. Something that happens quite often to starters is a ground problem between the starter brush plate, the starter housing and the engine block. Power gets to the starter brush via the power cable and travels through the armature winding and the negative starter brush and then nothing since there's an open circuit to ground between the negative brush and ground. As an auto mechanic, when the starter solenoid would click and no turning over of the starter, a smart smack with a hammer on the starter and away things would go again....until the next time. It was a sure fire way to determine that the starter just needed cleaning.
One thing to be careful of if you do decide to take the starter apart and clean it- Some people will paint all the parts before putting it all back together and the starter doesn't work. Paint is a great insulator of electricity. Understand the flow of electricity through the starter and don't make the mistake of painting the areas of the starter that flow electricity. The starter body needs a ground ground to the engine block. The starter brush plate needs a good ground to the starter housing.

That's my best advice.
Cheers,
KB

Post note- the show looks like it was a success. So nice to see all the old vehicles and all of the people that dressed up in time period clothes to add to the nostalgia.
Thanks for sharing Holger.

Hi Kawboy, thanks for you advice. The starter has been refurbished a few year ago by someone who did a good job I think. I did not refer to the famous click (and nothing afterwards) but rather to the sound a starter does, but does get only a very low amount of power. That lead me to believe it is the battery of some part from that family.

Yeah, the claim they had aver 1000 (4-digit number) old cars and bikes, from very small motorized bicycles to even a Bugatti. I did like the atmosphere as everyone who had been there enjoyed the old machines and shiny surfaces and was not in the "let us protect the environment and scrap these old machines"-mood

Holger

Hi again Holger,
Don't overlook the starter relay. lots of reports of failed contacts in the relay and probably due to overheating caused by too much cranking of the starter trying to get the bike running from cold with choke. Starters and starter relays don't like being run for more than 5 seconds and if you run the starter for more than 15 seconds, you need to give the starter a rest for a minute to cool down. Some guys will crank and crank until the battery is almost flat and that's a bad thing. if it doesn't start in less than 5 seconds, you really need to figure out why it won't start  and "fix" the problem. The choke mod Scotch came up with is a worthwhile mod and makes a huge difference.
It may be worth while to remove the cover on the starter relay and look at the contact surfaces and clean them up or replace the relay with a relay that can handle 200 amps.

Maybe the charging circuit has a problem as well. Check the 6 pin connector between the alternator field windings and the rectifier relay. It should be easy to find all yellow wires running through the connector