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Wiring Makeover - best practices please

J

JWHITE518

Guest
Connected to two AP-1's I have wiring for the following devices:
  • Motolights with relay
  • PIAA halogen lights with relay
  • GPS
  • V1
  • Star-Traxx
  • Hyperlite brake flashers
  • Mix-It
  • Heat Troller
  • and probably some I've forgotten.
It's simply embarrassing to look at my jumble of wires, even though I've tried my best to make it look neat. I need to be able to route the wires neatly in a common bundle and wrap it all in a nice loom. Some of the wires need extending. In the past I've used crimp connectors, but had lousy results. Maybe I need a better crimp tool? I've also used solder and shrink wrap. That works better but I've noticed that this makes the wires stiff and I worry about durability. I've read about butt splices but never tried them. Also, some of the wires have varying thicknesses. The common positive wire that feeds the PIAAs is really thick. The power harness that comes with the Garmin is really thin and delicate. I currently use Rat Shack wrapping stuff for a loom but I think it looks cheesy and is hard to work with. So:

What's the best way to make a wire longer?
How do you deal with connecting wires of different gauges?
What's the best wire loom and where do you get it?
How do you label your wires? (or do you eschew labeling the pairs and just use a master diagram?)
When a device comes with an inline fuse, but you're already connecting it to a fuse block, do you eliminate the inline fuse?
Do you tin the bare end of a wire that you're screwing into an aux fuse block?

Who's got photos? I know some of you BMW folks are really good at this. I'm really hoping you can share some expertise. Thanks.
 
You comment you have not had good luck with crimped wire connections. Likely, you're not using the correct crimping tool. They don't sell "proper" crimp tools in auto supply and small hardware stores. Get a Klein 1005 Crimp tool. When using the tool orient the seam in the round lug/splice away from the tooth in the crimper and squeeze the tool until the tool stops meet. I guarantee you this will make decent lug and butt splices. These crimpers aren't cheap, you'll pay $20 or more for a good lifetime use tool. Get a Klein 11045 wire stripper too. You'll need a decent stripper to reliably strip teflon wire and to not nick wires when stripping. While you're blowing all this money pick a good pair of needle nose pliers too (like a Klein D-3203-5). So, you'll have $50-$60 in wire working tools, but you will notice the difference. NO, a Harbor freight best quality won't do. Bite the bullet get a Klein set, you'll never regret it.

A proper crimp has two crimps per wire one for the electrical bond and one on the insulation for a strain relief. The electrical bond is a real grunt smasher, the strain relief is a gentle crush to the insulation just to hold the wire. Thus, a butt splice will require 4 crimps.

I label wires with white flag zip ties, write on the flag with Sharpie permanent markers. One with a fine point, not the one you used to obliterate the name on the last cardboard box you shipped.

Cut and run all the wires you'll have in a bundle and zip tie them together. Then pull out the wires in the locations they'll go and tape the bundle at each wire exit. Clip off and throw away the temporary zip ties. Making the bundle like this will make a neater bundle than running each wire separately and then bundling them. This will, however, waste wire, get used to it, it isn't going to run you into the poor house. Use different colors to aid in tracing the bundle even though you've marked each wire. If you run a heavy wire supply (+, positive) to a piece of equipment use a similar size wire (or bigger) for ground too. Hot colors are for +, Positive (red, yellow, orange) cold colors are for -, ground (black, green, brown). Use teflon insulated stranded wire, the more strands the better. Teflon will be harder to strip the ends off, but it will resist hot spot melting and it is somewhat more resistant to pinch shorts (like when you bolt the tank down on top of a wire). When you tape the bundle use REAL Scotch brand electrical tape. The adhesive will stick and the plastic will lay flat. Tape the wires and wire bundles to the tubular frame members it will look a lot better than zip ties. Don't cut the tape after wrapping it around the application, pull it to snap off. This will stretch the end slightly and make it lay flat forever--that's why you're using real Scotch electrical tape, it does make a difference.

I always tin the wires I put under screw clamps. Be careful, just tin the very tip. You're tinning the tip just to keep the strands together, not for mechanical support. You don't want a fatigue break because you tinned the last inch of wire. It is not desirable to tin wire for crimps. Soldered wire splices are less desirable than good crimped joints because they are prone to fatigue fractures (breaking) from vibration inside the insulation where you can't see.

Heavy current draw equipment uses heavy wire, e.g., heated clothing, lights. Light draw equipment, sound, gps, radar detector equipment can use smaller wire but don't try to save money on wire and get the smallest possible. Small wire gets smashed easier and shorts out. Pick a smaller size only because it is easier to work with. The fuses in wiring are to protect the WIRE, not necessarily the equipment although it does that too. When a wire gets smashed or a job gets bungled, the fuse protects the wire from going up in flames and burning up the bike.

If you have lots of wires to connect to a battery, spend the money and buy a fuse block. Fasten the fuse block down with nuts bolts, screws. don't zip tie or tape it down. If you do this you can cut off the in-line fuses. Fuses are always as close as possible to the battery.

I'm sure I forgot a few items here, but this will get you off to a good start.
 
That's about as good a "short course" on wiring as I've ever seen. Ditto on spending the money for quality tools that will do the right job. Don't be penny wise and pound foolish with the wire or the connectors you are going to use. I've spent a lot of time helping my kid's friends sort out a typical kid's wiring job on their cars and it isn't worth doing it the cheapest way possible.

My only suggestion, if you were looking to do a lot of wiring work, might be to get a ratching crimper. Other than that, listen to what Dave says.
 
In the past I've used crimp connectors, but had lousy results.

Who's got photos?

I've always soldered my crimp connections for a trouble free life-long connection. The trick is to just solder the tip where the wire protrudes from the barrel. That means applying heat first (which is what you should do) and then dabbing a bit a solder to the end.

I also use Molex connectors and gold pins.


Photos? Well these links might help give you some ideas.

R1150 GS Blue Sea 5025 Fuse Block Install

R1150 GS Driving Light Relay & AutoSwitch Install
 
Sealing butt splices

Anchor brand makes butt splices that have a shrinkwrap type outer cover. After double crimping each end, you apply a little hot air, and its watertight. You'll find them at marine outlets most likely.
 
Excuse me I forgot to answer your questions.

What's the best way to make a wire longer?

The best way is to entirely replace the wire. Sometimes if the wire is in a factory loom and not replaceable in the loom, I run another wire outside the loom and leave the original wire in as a spare. If you feel you must add on to the existing wire a butt splice with a crimp is the best way.

How do you deal with connecting wires of different gauges?

Once again a butt splice. If one of the wires is quite a bit smaller than the other and is really difficult to crimp, fold the smaller wire once (to double the "size") and try the crimp again.

What's the best wire loom and where do you get it?

Wire or Loom?

Wire--As I noted before stranded wire with more strands is better, with teflon insulation. Lots of strands makes the wire very flexible. If you have the chance look at a welding cable, it's good example of extreme flexibility in a very large cable size. Buy wire in small spools at specialty electronic supply houses or on the net.

Loom:
--In the bad old days nylon tie cord was used to make looms. You can use zip ties instead, get the smallest possible zip ties you can find and orient the locks out of view.
--A woven nylon sleeve is great and also the most difficult to work with and impossible to find.
--A split plastic sleeve sold as wire loom is convenient but rarely looks good.
--A flexible non-split plastic sleeve works for short runs only and wire split outs have to handled with multiple pieces of sleeve.
--Plastic non-adhesive tape like they use on new cars is very difficult to do by hand, use the next method instead.
--The most straight forward approach is a taped bundle. Taping the entire run makes the bundle too stiff. So you tape at each split out and then every 3 to 4 inches along the length. You need to lay the bundle in position before starting the taping or it will have kinks at the bends. So, you use loose zip ties to hold it together before you use the Scotch Electrical tape to make the bundle like a loom.

How do you label your wires? (or do you eschew labeling the pairs and just use a master diagram?)

Noted in previous response, use color codes and write on zip tie flags. You'll lose the wiring diagram.

When a device comes with an inline fuse, but you're already connecting it to a fuse block, do you eliminate the inline fuse?

This is a trick question and needs two answers.

Normally, use only one fuse per circuit, a fuse block if properly mounted (protected and sturdy) is more reliable than an in line fuse.

Unless there is only one fuse in a fuse block and you are feeding multiple circuits from this one fuse. In which case, replace the block with block with individual fuses for each circuit, or use inline fuses from that single fuse block. You should avoid using 10 amp fuses to protect small current draw electronics, e.g., MPEG players, GPS units. For those use what the manufacturer recommends, which will likely be an amp or less.

Do you tin the bare end of a wire that you're screwing into an aux fuse block?

Noted in previous response, but be careful to only tin the tip. Stiff wire (due to excessive tinning) extending from the block will be a fatigue weakness point.

------------------

Zip Ties--if you can find them Nylon zip ties are better than generic plastic ties. They are stronger (they will cinch down tighter, sometimes too tight) and are more durable (they won't age crack) in other words they last longer than plastic. I am not sure about their sun resistance though. Never-the-less, they are fairly expensive and will be available only at specialty electronic supply shops. If all you have available is black, sun resistant ties, then use them.
 
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