Introducing flexibility with lighting and racks

[navrig]

I have a gravel bike which I intend to use for occasional touring.  It has a front hub dynamo connected to a crown mounted light.  I have recently fitted a rack mounted rear light.  I ran the cable from the rear to cable coming from the front light fixing it to the rack, seat tube and up the down tube.  The 2 cables are soldered and wrapped in shrink wrap.

I have a long tour planned next year and the bike is set up for that tour.

When I come back I want to strip the mudguards and rack and fit more chunky tyres for gravel riding.  I will have to break the cable between the two lights and secure the loose end connected to the front light.

Is there a reliable and recognised push fit or screw connector for this purpose?

Where is the "best" place to locate this connector - close to the front or the rear?

[julk]

I have found the supernova gold plug set works well for me.
https://supernova-lights.com/en-en/products/supernova-goldstecker-set

[Chris2020]

Has anyone used these?
https://www.dyna-snap.com/
https://www.instagram.com/p/B9rHaRKFKv9/?hl=en
(I haven’t but thought they look pretty nifty)

[mickeg]

When I set up my first dynohub lighting system, I saw that B&M was using 2.8mm spade connectors, so I bought a bunch of extras and I use those where I have a place where I might want to disconnect some wiring later.  They are not fancy and do not look as great as some of the other options, but they do the job.  If I need them to hold tighter, a pliers solves that.

If anyone is interested, on a different forum I described how I wired up my rando bike for lights, that link is at:
https://www.bikeforums.net/electronics-lighting-gadgets/1228845-wiring-up-dyno-powered-lighting-system-usb-charger.html

[navrig]

Has anyone used these?
https://www.dyna-snap.com/
https://www.instagram.com/p/B9rHaRKFKv9/?hl=en
(I haven’t but thought they look pretty nifty)

Thanks.  I think I'll give this a go. Not the cheapest but it looks to be the tidiest solution for when the rack and rear light are off the bike.

I'll also have a rethink on the cable routing.  I think it wold be tidier if the cable from the front light was pointing down when the rack was off.

[PH]

OK, I will get to the question,but first a couple of other things to consider:
First, I'd leave it till after your tour.  You may find that the rack has become indispensable and/or the 650g saving isn't worth bothering with.  If you decide the rack may remain useful and are still bothered by the weight, there's always the titanium option to bring it down to 360g.
If the rack really does have to go, you could move the light rather than remove it.  I've assumed you're keeping the front light, so you're going to want something on the back.  It could move from the rack to a bracket on the seat stays where the rack currently attaches to the frame.

To your question, I said I'd get there   
If you remove light and rack, I'd use small spade connectors as mickeg suggests, I don't see any reason to make it more complicated.  Where you put the join, depends how you have the cable threaded.  Unless there's other determining factors, I'd have the connection close to the front light.  For occasional use I really wouldn't consider the Dyna Snaps, they're big, ugly and expensive, unless you're using the frame as an earth you'll need two.  They might be great if you're taking a wheel out twice a day, total overkill for what you describe.  If the spade connectors don't appeal, SON make a very neat jackplug, single plug with an outer and inner connection. I have a light that came with one fitted, apparently they are awkward to solder, so probably a job for someone with those skills:
https://www.sjscycles.co.uk/dynamos/schmidt-2pole-connection-for-soncoaxial-cable-connector-set-male-female/

[martinf]

I have one bike that has a "temporary" rear rack fitted.

The dynamo lighting at the rear is a mudguard-mounted B&M Secula.

Rack and mudguard stays are independant from each other, so rack removal consist of undoing four 5 mm Allen bolts

For my secondary rear lamp I have a B&M TL-LD1100 battery lamp.

This has two Cateye brackets.

First bracket is permanent and is mounted to the mudguard at the point where the highest stays join (the TL-LD1100 is relatively heavy so I don't want it on unsupported plastic). This is low enough to be clearly visible through at least 180 degrees when have just a saddlebag and no rack. When the rack is fitted, a lamp in this position is partially obscured by luggage.

The removable rack has a plate at the rear for a lamp bracket, so I have a second Cateye bracket fitted there. 

This setup only works with mudguards, which I find are indispensable for my type of riding. Even on dry days I often go through shallow puddles or (worse) ride on a road where a farmer has spilled some pig slurry.

I'm not bothered by the slight extra weight of the rack, so it has stayed since I fitted it. But I have another bike without a rear rack and I might want to transfer the rack to this in the future, rather than buying another rear rack that is only used occasionally.

[mickeg]

One other thought.  I know that you already did the wiring, so this would mean undoing some of that later.

On my road bike, that is a coupled frame (the frame can be split into halves for shipping), so I did not want to have any extra complexities when I split the frame because to pack the bike in the case I have to remove a lot of stuff from the bike.  Thus, I just temporarily wired the taillight wire by wrapping it around tubes and anything else that was handy to make it easier to remove later.  Takes me five minutes to temporarily install or remove the tail light.

Also did the same on my Nomad Mk II which is an S&S coupled bike, when I do a bike tour I do not fit my dyno powered lights on it, on such tours the dynohub is only used for battery charging.  Thus, I wanted to be able to completely remove the taillight wiring.  On that bike I only run dyno powered lights when near home, not on a tour.

[navrig]

Thanks guys - some sound advice and suggestions there.

Currently I have not cut out any of the cable provided with the lights.  Both were quite long.  I've run the FL cable from the crown down the downtube and under the BB.  It meets the RL cable half way down the seat tube where they are soldered and have heat shrink wrap.  The RL cable excess is wrapped around the horizontal tubes which connect to the top lugs.  These tubes do not take any abrasion from anything attached to the top of the rack so they should be safe.  The cable is wrapped around the two tubes in a figure of 8 configuration and tied with a couple of cable ties.

Given this setup has survived a short tour already and several very wet rides I probably won't change the configuration until after the tour. 

The "need" to remove the rack after the tour will largely depend on how I get on during the tour.  If it is a great success and I am inclined to do an annual tour then I may leave the bike as-is.  If my regular riding buddies are doing off-road stuff on their gravel bikes then the mudguards will come off and wider tyres will be fitted.

All that said I am very comfortable with my toolkit and taking off and putting on racks and mudguards is not an issue.  I just want a suitable cable configuration which suits chopping and changing the bike setup.

[navrig]

I am now about to make these modifications.

My tour was great and whilst I am planning more the bike will be run as a gravel bike over the winter and spring.  I have swapped the 700c wheels for a set of 650b wheels with 48mm off road (MTB almost) tyres, removed the rack (and mudguards).  The cable between the rear and front lights was cut to pack the box for flying back from Athens.

I am still looking at connectors.  Spade connectors seem to be the simplest but I am concerned about potential corrosion given most are made of a cheap mild steel.

I have not lost any cable from either the front of rear light so the connection point could go anywhere - currently I am inclined to make the connection near the top of the down tube but that means cutting the FL cable very short. 

Any thoughts?

As I have swapped out the wheels the 650b doesn't have a hub dynamo and currently the connector is simply taped to the bottom of the fork.  A simple solution and as long as I keep it dry I guess shouldn't be a problem. 

Any thoughts?

[PH]

My opinion hasn't changed in the year this thread has been dormant

I'd use small spade connectors as mickeg suggests, I don't see any reason to make it more complicated.

I think the fear of corrosion is unfounded, SON hubs still use spade connectors in a far more vulnerable position, if it was an issue I think they'd know about it.  If you're still concerned, a smear of Vaseline, or marine grease every year or so would keep them like new.  Or if the aesthetics bother you, and you're not frequently reconnecting, you could heat shrink over the joins, it's easy enough to remove and redo.  Whenever you're introducing connectors it's neater IMO to stagger them.
If long term I was planning on swapping a dynamo in and out, I might be tempted to change the lights to battery and use the dynamo as a charging device.  That's my plan should I use the folder to tour again, the light is vulnerable when folded and last time I toured with it, I carried the light around without using it.

[Andre Jute]

Breaks in electric cables should preferably be on a vertical section of the cable run. The shrink-wrap on the higher piece can be cut long to form a sheath for the junction, overlapping the junction so as to keep water out. This requires some care with your heat source when shrinking. At the junction with the hub dynamo and the lamps, there should be a drip loop to avoid leading water straight into expensive bits -- not elegant, but not all lamps are waterproof and some expensive lamp makers including B&M are pretty casual or absent when it comes to intrinsic waterproofing of lamps because they presume the lamps are intended for bikes with mudguards. If you use large and ugly splitters, they can be hidden behind the tubing.

[JohnR]

Here's the gold-plated solution https://www.sjscycles.co.uk/lighting-spares/supernova-qr-gold-connector-set-with-integrated-shrink-wrap/ .