R100 Gs PD - Charging advice - Help..😟

Bucephalus

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A couple of weeks ago I broke down quite suddenly, just after braking and indicating to turn right.

The bike cut out and stopped, the symptoms thereafter were of a completely dead battery, I assumed the last brake and indicate was the final draw on the electrical system.

I managed to start the bike being pushed by two strong men and limped home, I bought a new battery and was back in business.

However, after a few hours riding, I couldn’t restart the bike after a lunch break.

Recovered to a recommended local mechanic who called me a few days later, and said it’s not the regulator or rectifier which is the usual assumption as I’d fitted a brand new battery, but something to do with a bulb ( I think he said generator bulb) in the small dash.

He said the good news is that the bulb is about a £1.50 but he warns me it’s looking like the front of the bike has to be dismantled to get to it and his Labour Charge might be quite substantial to do the job.

Does this make sense to those that might know better than me.. :nenau
 
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Yes, that's right. If the alternator light doesn't come on when you turn the ignition key (but before starting) then the circuit has failed and that could be the bulb, which can actually stop the bike forom charging. Terrible design. Cost me abour £10,000 once, in that i took the fairing off to fix it and decided not to put it back on, ending up doing a massive redesign and refurb in the process, which was fun. I now have an LED charging light instead, on my Acewell dash.
 
Thank you so much Roberto for your help, it’s a relief to learn that a simple bulb can have such a major impact on the charging system.

It just didn’t sound right, combined with trying to get my head around the £150 cost to change a 💡 bulb..👌

I’m useless as far as anything practical goes, I can’t bang a nail in straight 🙄
 
I can’t bang a nail in straight 🙄
I’ve been a builder/roofer for 30 years and neither can I without a nail gun!

The system of using the battery light to supply the field coil on the alternator was common practice back in the day when these bikes were made. With the advent of led loghts there are better solutions but the system does rely on the light bulbs or equivalent resistance. Yours being a PD involves a bit more dismantling to get to this bulb. Easy enough to do.
 
A Silent Hektik permanent magnet 410W alternator and regulator are the answer to all the ills of the charging system. (y)
 
This is a great community of friends and font of knowledge, I will note the new 410w alternator advice, and maybe treat myself for my 73 birthday 👍
Having just had (last week) an expensive service and now this, I just want to get back on the road for now, thanks chaps 🙏
 
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This is a great community of friends and font of knowledge, I will note the new 410w alternator advice, and maybe treat myself for my 73 birthday 👍
Having just had (last week) an expensive service and now this, I just want to get back on the road for now, thanks chaps 🙏
I think there's a list of the common airhead GS problems somewhere. Not many of them, and they are all avoidable or easily fixable. You've had one of the most annoying. So shouldn't get another for a while! (i have an optimistic view of probability). Enjoy riding it! 73? That's about the same age that Ted Simon was when he did his last round-the-world ride.
 
IMG_2035.jpegI seem to be going one step forward and two back at the moment, he’s just phoned me to inform me the gaiter between the gearbox and drive shaft is split 🥴

Believe it or not I bought Ted Simon a beer in a quiet pub somewhere near Melton Mowbray, he was sitting alone and I joined him for an hour.

Perhaps I was hoping to hear some interesting tales and anecdotes, but I soon learned he was a very quiet and private man, who would skilfully turn the conversation back to my travels..I thought about this and understand now he wouldn’t want to be misquoted possibly after a conversation with a stranger in a pub.

I mentioned that I had read his first book; if I had it with me he could have signed it..He graciously produced a book a newer version and signed it..👌

I remember he was wearing a tan leather jacket, and red check lumberjack style shirt that night, and when I bumped into him about 10 years later at the Stafford Classic Bike show he was still wearing them, funny the things you remember.. :D

Assuming from the signature 1998.
 
That's nice. Very Ted. Listening is more important to being a travel writer than talking. He's good at getting other people to tell their stories.

The gaiter is a bit of a pain. Water in the drive shaft is not good, as they are dry and will corrode. I've never done the gaiter myself, but heard they can be really difficult to fit. Maybe theres something that can be wrapped around it as an easier fix?
 
First time trying to change the gaiter was a nightmare - second time much easier. The secret is to keep the drive shaft 'up' as far as possible, can't remember if I got it horizontal or not. Trying to put it on with the drive shaft angling down is ockurd to say the least.
 
That's nice. Very Ted. Listening is more important to being a travel writer than talking. He's good at getting other people to tell their stories.

The gaiter is a bit of a pain. Water in the drive shaft is not good, as they are dry and will corrode. I've never done the gaiter myself, but heard they can be really difficult to fit. Maybe theres something that can be wrapped around it as an easier fix?

Not difficult to fit really, just position the swingarm so it’s not pulling the gaiter off the flange. Easy to do if shock removed
 


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