Upgrading headlight lamp and wiring/heated grips question.

[ginny]

So, Having managed to disassemble the hornets fairing etc, I am going to fit a better main bulb (probably an osram night racer plus)

Since I have all the wiring etc exposed, I was considering re-doing the heated grips. Currently they are wired to the battery directly, so I have to remember to turn them off. Instead I thought attaching directly to headlight wiring would be good as there is always power to it (there is an in-line fuse in the grips wiring already)

However- will this reduce the power available to the lamp, and therefore reduce the effectiveness of main headlight?

I could wire to rear break light but that cable is further away to wire, not so obvious, and not so easily-open-to-manipulation/bodging.



TL;DR- Will wiring heated grips to headlight reduce headlight brightness?

Thoughts appreciated.

[bikenut]

dont do it!!

dedicated wiring for dedicated circuits, along with fuses.........unless of course you want the lights to just go out at night? or the wiring catch fire......interesting if your riding it at the time..........merry xmas and dont involve me in your accident.

[MarkJ]

I wouldn't run it in parallel from the front headlight, it could pop the fuse and you wouldn't be able to run the grips with the lights off.

I know you don't want to but using a relay from the rear brake wiring really is the best way. You could use a relay from the front headlight which shouldn't pop any fuses, but again you could only have them on with the headlight on.

[ginny]

Haha fair enough! A relay is just more effort, but if necessary I can do it... I say me but I know nothing about wiring, I would have been asking the father in-law for advice, so hopefully he knows about relays as well as basic wiring/splicing etc.

I should add that I ride with the headlight always on all the time anyway... lots of filtering.

Edit: Hows this?
https://www.amazon.co.uk/LD-12P-Automotive-Pin-Relay-12V/dp/B004UA61T0/ref=sr_1_1?ie=UTF8&qid=1356017598&sr=8-1

[orac]

if it was me i would take a feed of from the ignition (something like brake ligh feed should be fine), through the switch to a relay (coil side). the switch side of the relay takes a feed from the battery to the grips through a fuse of the correct rating

that relay yo linked to should be fine, woudln't think the grips would draw more than about 3amp
____________________
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"with nothing left to lose, there is everything to gain. It's not the size of the dog in the fight, it's the size of the fight in the dog"

[stinkwheel]

[ginny]

Thought I had replied to this... anyway.

Stinkwheel, that how-to looks brilliant. Complicated, but brilliant. I should be able to scrounge the wire up from the in-laws garage- trying to keep costs low and don't need 3 spools of wire sitting unused! had a recce today and he seems to have all the bleedin' connectors etc I could imagine!

Probably a bit above my level but nevertheless I shall have a crack at it.

Out of interest how do you know which are the ignition wires? Assuming you are looking at the big fusebox/plug where all the cables seem to go (under the seat on my hornet) that is.
I guess rear break lights are easier to identify, are they as suitable?

[stinkwheel]

[ginny]

One final question

The 2 devices I want to attach via relay have in-line fuses already. Grips and Cigarette lighter/12V socket for phone charging. I might just connect the socket to the battery as it will only be powered when I actually plug my phone into it.

Do I still need to insert the 2 separate fuses, as you have in your walkthrough? Or can I just have a direct feed from Positive terminal to relay?

Edit: scrap that- I have just realised that i can just insert the relay in between device and its in-line fuse serve the relay as a whole rather than just the device. The supplied cable for the grips is plenty to stretch from relay mounting position to h'bars. If that makes sense. At all.