1975 BMW R90/6 - Rocinante

Reaching out for some assistance here. If you've got airhead experience chime in if you can, please.

I've got nothing for electrical. Hook up battery (new and full charge), turn on the key, and nothing. I have to assume there's a blown fuse. Are the fuses on the back side of the connector board that's inside the headlight?

To backfill some info: After getting the new battery I hooked it up not knowing the wiring for the clock was shorted. The clock was connected as an "always powered" circuit. Of course it got hot and smelled bad and I managed to very quickly disconnect the battery. The little wiring harness for the clock will need to be replaced, no problem. There is also a small part of an adjacent wire that got melted, also an easy fix that I'll make. Months later I'm ready to get things going and with the battery connected I've got nothing.
 
What fuses are they? old school glass? they can be not blown but the clips can be corroded enough they won't pass power. I always swap to blade fuses so I can get them in a pinch easier, but emery cloth and elbow grease on all the clips will go a long way removing gremlins.
 
Oh Shitballs it's got a fubared old ceramic fuse panel. I'd be dumping that and getting something a lot more modern, those old units corrode and will cause all kinds of weird problems.
 
Maritime said:
Oh Shitballs it's got a fubared old ceramic fuse panel. I'd be dumping that and getting something a lot more modern, those old units corrode and will cause all kinds of weird problems.
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Maritime said:
What fuses are they? old school glass? they can be not blown but the clips can be corroded enough they won't pass power. I always swap to blade fuses so I can get them in a pinch easier, but emery cloth and elbow grease on all the clips will go a long way removing gremlins.
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I appreciate what you're saying but there ain't no way I'm gunna redo all the electrics on this thing. I just need to know where the fuses are. Pretty much has to be the main fuse blown to have absolutely no power when you turn on the key.
 
Also, 90% sure I have a spare fuse panel if it comes to that. It is in the headlight bucket. The retaining ring can be a bit tricky on them.
 
ridesolo said:
I appreciate what you're saying but there ain't no way I'm gunna redo all the electrics on this thing. I just need to know where the fuses are. Pretty much has to be the main fuse blown to have absolutely no power when you turn on the key.
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Just the fuse panel, not the relays and electrics the fuses look built into the panel but it was a 10 sec google. I need more time to find out more before knowing for sure. I know the GL had similar and I swapped those type out. One would fail when Inhit a big bump, shut the bike off then another bunp and I'd get power again
Was nuts as the thing looked ok but had a corroded spot that the bump would seperate then bump back together.
 
OK, finally found them. There are lots and lots of wires in that little bucket. Interesting, neither one looks blown. Guess I'll replace and see what happens.
 
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Hurco550 said:
Also, 90% sure I have a spare fuse panel if it comes to that. It is in the headlight bucket. The retaining ring can be a bit tricky on them.
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Sorry, I missed this msg last nite, Thanx for the offer and if I end up having to go that way it'll be much appreciated. I went out and poked around some more and found the things. For some reason I had read, somewhere, that the fuses were on the back side of that board and I was looking for old glass fuses, forgot about the old(er?) ceramic ones. (Have owned three old Beetles over the years, how could i forget ceramic fuses?) Anyway, I'm gunna venture out this morning to get some and see what happens. They don't look like they're blown but the main doesn't look good either.
 
ridesolo said:
Sorry, I missed this msg last nite, Thanx for the offer and if I end up having to go that way it'll be much appreciated. I went out and poked around some more and found the things. For some reason I had read, somewhere, that the fuses were on the back side of that board and I was looking for old glass fuses, forgot about the old(er?) ceramic ones. (Have owned three old Beetles over the years, how could i forget ceramic fuses?) Anyway, I'm gunna venture out this morning to get some and see what happens. They don't look like they're blown but the main doesn't look good either.
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Yep, they can look fine but be bad. You can check them with a multimeter or a test light and battery.
 
I got a couple of fuse holders and some small blade fuses and eventually going to try soldering them to the board. In the mean time I was able to get some power flowing and caught this: (First time the starter has done it's thing in around 35 years.)



And it's even got spark:



So... I guess I just gotta add some gasoline and see what happens.
 
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It lives! I was pleasantly surprised that once I plumbed up the tank and added gasoline it didn't even have to grind much... it popped right off. That's the good news. The bad is that gas was running out of the left carb float bowl. Took the carb off and messed w/ the float and needle valve and got that taken care of.

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Unfortunately it only wants to run on the right cylinder. Left side has spark so it's got to be a fuel issue. I'll take that left carb off and go through it. I'm sure it's probably something I didn't do right when I refreshed it a couple years ago.

CycleTech Rick called to say the tires are in so I went over to pick up the front. We were both surprised by the tread pattern because it was completely different from what we thought was being ordered; same name, different tread pattern. However what we got is the right size and looks pretty good so I'll go with it. The second surprise was that for whatever reason the rear tire was cheaper by $5 than the front one.

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I didn't feel like digging into the carb any more today so I mounted the caliper for the front brake. I'll pick up a bottle of brake fluid tomorrow and get that buttoned up. Looks good, though!

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doc_rot said:
That’s awesome. Love big brakes on vintage wheels.
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As @doc_rot said: "Love big brakes on vintage wheels." Amen, brother!
 
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New rear tire is mounted.

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And the rear fender is back in place. The thing is starting to look like an honest to goodness motorbike.

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Yep. The next project is to install and wire up turn signals and tail/brake lights in the panniers. I've found some very nice LED units; amber for the turns and red for the tail/brake. They're only an inch or so in diameter and will fit in the flat spot at the back that's currently filled w/ a single red light that looks like it came directly from a semi trailer. Though the panniers are easy to remove my plan is to pretty much have them on there full time so having the rear turn signals set up there is, to me, a no brainer. I do need to wire them up so they're easy to disconnect, though, so I'm going through the mental exercise to plan out something that's neat and efficient as possible.

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The other day my sis-in-law wandered onto the shop and told me how nice this beast is looking. Then she pointed to a scratch on one of the saddlebags and asked, "How hard is that going to be to fix that?" I had to explain to her that the old girl had earned every scratch and ding and my intent to leave most everything as-is to reward it's life accomplishments.

@Hurco550 stopped by the other evening and we fiddled a bit with things. He didn't criticize much, didn't shake his head in disappointment, or laugh so must be it's going together satisfactorily. The good news is that he wouldn't hesitate to tell me if something was sketchy.

Here's a shot of the back. With the exception of the tail light and right muffler that's getting a small repair, this is pretty much how the thing is going to look from the rear. Eventually I'll find a solo seat and a rack instead of the original couch, but I'm 100% sure I'm not going to miss the tail trunk.

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A few posts back I mentioned the SS bolt/nut/washer set I got for it. They are divided into over 30 different plastic bags. The bags separate them into sub assemblies. The set is for /6 and /7 machines so there are some duplicates such as parts for both drum and disc rear brake. I've been slowly going through them and at times I've wondered what the "extra" pieces are for. Today I noticed the rubber mud flap on the rear fender and realized what the extra parts in the Rear Fender bag are for:

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I don't think anybody would have noticed there was a Philips head bolt there before, but the attention to detail is nice.

While I was taking pix I remembered that I hadn't mentioned the mirrors I got for it. I went through hundreds of ads for bar end mirrors and, though there were many duplicates, I came across this one that was singular and just what I wanted. Levi did a masterful job with them and the flat handlebar I had and they came out pretty nice.

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I had originally hoped to mount them turned so they pointed inboard and over my hands on the grips, but when I tried that out it was obvious they would interfere with my hands so I had to turn them outboard.

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