401
Re: Big Block K100 Thu Aug 22, 2024 10:53 am
Two Wheels Better
Moderator
I got round to sorting out the charging issue with BB that left me waiting at the roadside for a few sunny hours for my mate with a pickup back in June. The battery was suddenly flat twenty miles after breakfast on the second day out of a five day tour. It had fired up strong that cool morning. My multimetre indicated 9 volts at the battery. I couldn't bump start the engine. No one I enquired of had jumper cables. It was a lovely early summer day at the seaside on the Washington state Pacific coast. I rang my mate Bob. Then I waited.
Fast forward two and a bit months and it's been a heady summer of riding while BB collected dust to one side of the garage. Out came the tools. I'm feeling much better after a 17 day illness had me sofa bound.
I have a coupla spare 50amp alternators so removed the seemingly defunct unit - no connections were dodgy, nothing loose. I mentioned somewhere, I think, that the baby bottle overflow coolant bottle had split. Sure enough, pink Zerex had trickled down the top of the gearbox and possibly been inhaled at the back of the alt. But the bike always did have a slight running rattle that I thought came from somewhere nearby, but I could never ID it.
The monkey nuts were intact. I slipped a new set in and as I do, gave the three way metal drive tangs a slight shot of silicone spray. This eases the forward movement as I push the alt to home against the block. Aligned, I tightened the three Allen head screws. Ain't that bottom 7 o'clock one a pain in the arse to get to!? Cables attached, spade connector on, battery in, leads tightened, and held down by the belt & buckle I use like the kewl kids do on their café racers.
12.6 volts wasn't enough from the 12amp AGM so I jumped from an old (ancient) Shorai lithium I had lying round with 13.2v in it. Up she fired and settled into a steady idle. I whacked the multimetre onto the battery posts to see barely 12.75v showing. A quick stab of the throttle and it jumped to 13.9v. A real rev and it peaked at 14.3v. And guess what, no running rattle any longer. That alternator may just have been a noisy one. The drive cup does move considerably more in and out than the other units in my spares supply - a bad bearing, perhaps. The one that went in had barely a mm free play, as normal. I replaced, temporarily, the dozen year old baby bottle with a small sturdy Nalgene-type bottle. A metal replacement is incoming.
I ran the engine through two coolant fan cycles on the main stand. No rattle arrived. Don't those three row radiators take forever to warm up!? Rain is imminent so I didn't dress for a test ride. Perhaps mañana.
A definitive fix?
Fast forward two and a bit months and it's been a heady summer of riding while BB collected dust to one side of the garage. Out came the tools. I'm feeling much better after a 17 day illness had me sofa bound.
I have a coupla spare 50amp alternators so removed the seemingly defunct unit - no connections were dodgy, nothing loose. I mentioned somewhere, I think, that the baby bottle overflow coolant bottle had split. Sure enough, pink Zerex had trickled down the top of the gearbox and possibly been inhaled at the back of the alt. But the bike always did have a slight running rattle that I thought came from somewhere nearby, but I could never ID it.
The monkey nuts were intact. I slipped a new set in and as I do, gave the three way metal drive tangs a slight shot of silicone spray. This eases the forward movement as I push the alt to home against the block. Aligned, I tightened the three Allen head screws. Ain't that bottom 7 o'clock one a pain in the arse to get to!? Cables attached, spade connector on, battery in, leads tightened, and held down by the belt & buckle I use like the kewl kids do on their café racers.
12.6 volts wasn't enough from the 12amp AGM so I jumped from an old (ancient) Shorai lithium I had lying round with 13.2v in it. Up she fired and settled into a steady idle. I whacked the multimetre onto the battery posts to see barely 12.75v showing. A quick stab of the throttle and it jumped to 13.9v. A real rev and it peaked at 14.3v. And guess what, no running rattle any longer. That alternator may just have been a noisy one. The drive cup does move considerably more in and out than the other units in my spares supply - a bad bearing, perhaps. The one that went in had barely a mm free play, as normal. I replaced, temporarily, the dozen year old baby bottle with a small sturdy Nalgene-type bottle. A metal replacement is incoming.
I ran the engine through two coolant fan cycles on the main stand. No rattle arrived. Don't those three row radiators take forever to warm up!? Rain is imminent so I didn't dress for a test ride. Perhaps mañana.
A definitive fix?
