Woo Hoo! A Big Project!

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Chuey
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Re: Woo Hoo! A Big Project!

Post by Chuey » Wed Apr 13, 2011 11:57 pm

Mellville, I'm really challenged electrically but one thing I thought of that could be your problem is the big red wire that goes in the middle of the starter relay. There is a receptacle for the relay to plug into. It has spade connectors for the prongs of the relay. If the big red wire in the center is slipping down out of the bakelite receptacle, it may not be making proper contact with its male counterpart.

Or, I could have just said "Check that the red wire in the center of the starter relay is connected well." :)

Chuey

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melville
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Re: Woo Hoo! A Big Project!

Post by melville » Sun Apr 24, 2011 6:12 pm

Not much to report. Rain and other commitments are conspiring against progress. The front fender is now mounted:

Image

And the starter relay is continuing to vex me. A new one is $100+, so I've been cleaning terminals and checking voltages at the various connections trying to figure out what's missing. Especially the big red connections, Chuey! Next is probably trying a regular 30A Bosch relay, bypassing the neutral/clutch lockouts to see if the problem is, in fact, the relay.

Next weekend I'm attacking the loose nut holding the handlebars with the MSF course. That should provide inspiration to finish this beast.
Call me Mel. Some years ago- never mind how long precisely- having little or no money in my purse, and nothing particular to interest me at home, I thought I would ride about a little and see the other parts of the world.

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dougie
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Re: Woo Hoo! A Big Project!

Post by dougie » Sun Apr 24, 2011 6:23 pm

I like the VW toolbox/workshop :mrgreen:
I've spent most of my money on women, motorcycles, and beer.
The rest of it I just wasted.

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melville
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Re: Woo Hoo! A Big Project!

Post by melville » Sun May 01, 2011 4:14 pm

Loose nut holding the bars slightly tightened--I have passed the MSF BRC! Perfect scores but for being a little timid on the brakes. Instructor didn't buy the "But my Airhead can only brake that hard" line.
Call me Mel. Some years ago- never mind how long precisely- having little or no money in my purse, and nothing particular to interest me at home, I thought I would ride about a little and see the other parts of the world.

Chuey
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Re: Woo Hoo! A Big Project!

Post by Chuey » Tue May 03, 2011 11:58 am

It's all that bicycle riding. That puts an intuitive skill in you. That, or it eliminates you. Anyway, good going.

Chuey

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melville
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Re: Woo Hoo! A Big Project!

Post by melville » Sun May 15, 2011 5:08 pm

The starter relay has been vexing me. I've cleaned the terminals, checked the wiring, defeated the interlocks (for test purposes only) and never got more than a faint click coming from some other thing in the headlight bucket. When I started this project, the relay gave me trouble as well, but functioned decently once I cleaned the terminals. Move forward a year to the reassembly stage, and it refused to function. Today I rechecked the wiring of the starter switch circuit and it all seemed fine--continuity as it should be, switch functioning, everything that was spozed to be hot was hot, everything that was spozed to be ground was ground. I then hooked up a couple leads to the terminals of the battery and tried hotwiring the switch side of the relay and got nothing. I've been resisting replacing the relay because it's a specific BMW $$$ part, toward the bottom right of this diagram:

Image

But if you look at the schematic it looks like a regular old DIN relay with a couple extra terminals to connect the blue wires, which are part of the charging system. This was confirmed for me when I got the most recent issue of BMW Owner's News where Saint Matthew of Parkhouse replaced the BMW part with a plain old DIN relay, and connected the blue wires separately to fix his old /5. I have no idea how that got published, as I'm sure that BMW doesn't want us buying $5 relays from NAPA instead of $100 relays from the dealer. So anyway, I found a spare relay in my pile o' VW stuff, hooked it up to the load (starter) wires, and hotwired the switch side as before. NaNaNaNaNaNa! I then hooked it up more properly to the switch circuit, and was able to run the starter off the button, as God and Max Friz intended. Here's how it looks now. I'll be installing it properly soon:

Image

Image

This frees up a lot of mental space for me to pursue other electrical anomalies. Also, later this week, Mrs. melville and I will discuss moto budget for the near future.
Call me Mel. Some years ago- never mind how long precisely- having little or no money in my purse, and nothing particular to interest me at home, I thought I would ride about a little and see the other parts of the world.

Deleted User 62

Re: Woo Hoo! A Big Project!

Post by Deleted User 62 » Sun May 15, 2011 5:20 pm

Mel, I'm not sure if you realize this, but those two blue/green wires connected to the factory relay don't actually do anything in the relay. They can just be connected together with a short strip of brass. Not sure why BMW did it this way, maybe it was just a convenient place to connect the two wires from separate harnesses (and make it a one of a kind BMW relay in the process).

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melville
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Re: Woo Hoo! A Big Project!

Post by melville » Sun May 15, 2011 5:23 pm

Tim Shepherd wrote:Mel, I'm not sure if you realize this, but those two blue/green wires connected to the factory relay don't actually do anything in the relay. They can just be connected together with a short strip of brass. Not sure why BMW did it this way, maybe it was just a convenient place to connect the two wires from separate harnesses (and make it a one of a kind BMW relay in the process).
Yeah, that was the sudden realization from Parkhouse's article confirming what I thought I was seeing on the schematic.
Call me Mel. Some years ago- never mind how long precisely- having little or no money in my purse, and nothing particular to interest me at home, I thought I would ride about a little and see the other parts of the world.

Deleted User 62

Re: Woo Hoo! A Big Project!

Post by Deleted User 62 » Sun May 15, 2011 10:04 pm

melville wrote:
Tim Shepherd wrote:Mel, I'm not sure if you realize this, but those two blue/green wires connected to the factory relay don't actually do anything in the relay. They can just be connected together with a short strip of brass. Not sure why BMW did it this way, maybe it was just a convenient place to connect the two wires from separate harnesses (and make it a one of a kind BMW relay in the process).
Yeah, that was the sudden realization from Parkhouse's article confirming what I thought I was seeing on the schematic.
Well hey, I just went back and actually read your post. You know, the one with the picture? Sounds like you are, as we say in Hawaii, "on it like an opihi" (pronounced oh-pee-hee: a small limpet-like mollusk).

Chuey
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Re: Woo Hoo! A Big Project!

Post by Chuey » Thu May 19, 2011 12:40 am

Mellville, check out ebay item #140521694058. Starter relay.

Chuey

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