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1Back to top Go down   Mounting floodlights on LFB Empty Mounting floodlights on LFB on Fri May 22, 2015 8:31 am

Dai

Dai
Life time member
Life time member
I had a PM asking how I'd mounted the additional lights on LFB; as my avatar is well out of date and I've also changed the standard K100 headlight for a 7" round Cibie, I thought it might just be of interest to someone else too.

The headlamp shell I chose is a replica Honda CB900F type. It's 190mm across at the widest point and is the biggest that will fit in the fairing opening and still allow a small amount of room for adjustment. The reflector it came with was immediately dispatched to the bin because even a cursory visual inspection showed that the beam pattern was going to be utterly useless, so a brand-new Cibie was fitted instead. I mounted the shell from the back of the fairing bracket. There's a lot of trial-and-error in the shape of those brackets which is why they're bolted to the fairing spider rather than welded to it. The odd wave is caused by the need to avoid the lower yoke.

Mounting floodlights on LFB Ch1

I used 3mm plastic card to form the new headlight opening - an A4-size sheet is just wide enough and no more. Cutting out the 195mm circular opening was fairly easy; I marked it out with a pair of compasses fitted with a scribe rather than a pencil and then patiently followed up with a Stanley knife. I then reinforced the edges with additional 3mm plastic card. It's held in place with three aluminium brackets screwed into the original headlight mounting holes and backed with rubber to provide seating pressure. I did consider using aluminium sheet for this job but the headlight opening has a slight curve at the top. Plastic card will take it up but you could spend hours trying to get ally to fit precisely. The odd shape at the top corners is caused by needing to fit around the RS screen and the bits at the bottom corners are the backs of two 1.5w Cree marker lights. Yes, one did get off position when the hole was being drilled - dammit.

Mounting floodlights on LFB Ch2

Finding a mounting point for the spotlights was reasonably trivial. I used the horn mounts and moved the horns to the bottom fairing mounting. I then simply stuck a pencil through the captive nuts to mark the fairing in the right place. I used a pair of naked K100 headlamp rubbers to provide anti-vibration mounts (these needed a 20mm hole in the fairing) and pushed a tight-fitting M8 I/D tube through the rubber to butt up against the horn captive nut. Right-angle brackets were then fabricated to suit the width of the spotlights (5"). The positioning of these holes can be seen in the pic above too.

Mounting floodlights on LFB Ch3

Figuring out the auxlight mountings was a bit more complex. There were a couple of things in play here; I wanted to be able to remove the fairing without dismounting the auxlights each time and I wanted to use 5.75" headlights. This meant that the auxlights had to be parallel with the original headlight to get the narrowest mounting point (define 'narrow'... ). The only available point to take the weight was the bottom of the fairing spider, so I welded in a piece of 3mm flat bar as far forward as possible. Despite that, the lights bar still had to be dropped down by 60mm and offset forward to clear the fairing.

Mounting floodlights on LFB Ch4

The width of the lights bar was dictated by the width of the fairing at that point. It's 14mm tube with 1.5mm wall thickness. I plugged both ends and threaded them to M8 so that I could change the type of auxlight and only have to make new brackets to suit. Finally, to be able to remove the fairing with the lights bar in place I cut slots in the chin piece.

Mounting floodlights on LFB Ch5

Truthfully, they really aren't as ugly as they look in that picture! All the bulbs are Osram Nightbreakers.

Currently LFB is off the road for a 70,000 mile service and a complete new wiring loom - you can see the tails hanging off the bench in the first picture. Those Eccentrics on the run to Newgrange when Bill was here have seen the complete setup. 88KE commented that the marker lights were very effective. I'm childish - I take great delight in getting my own back on the buggers coming the other way who won't dip their headlights. The first time I did that I got a bit of a shock: even with his lights on full beam I could still see by him!!!


__________________________________________________
1983 K100 upgraded to K100RS spec, 1987 K100RT
Others...
1978 Moto Guzzi 850-T3, 1979 Moto Guzzi 850-T3 California,1993 Moto Guzzi 1100ie California
2020 Royal Enfield Bullet 500
    

2Back to top Go down   Mounting floodlights on LFB Empty Re: Mounting floodlights on LFB on Sat May 23, 2015 5:43 am

charlie99

charlie99
VIP
VIP
good detail dai

thanks for the post


__________________________________________________
cheezy grin whilst riding, kinda bloke ....oh the joy !!!! ...... ( brick aviator )

'86 K100 RT..#0090401 ..."Gerty" ( Gertrude Von Clickandshift ) --------O%OMounting floodlights on LFB Au-log10

'86 k100 rs.. #######..  "Fred " (f(rame) red ) ( Fredrick leichtundschnell ) - -
bits and pieces from many kind friends across the k100 world ...with many thanks ..
    

3Back to top Go down   Mounting floodlights on LFB Empty Re: Mounting floodlights on LFB on Fri Jun 05, 2015 9:51 am

Dai

Dai
Life time member
Life time member
I got asked to add a bit more detail to this, specifically about the headlamp mounts and the wiring. I more-or-less guessed the headlamp brackets. To get the correct angle on the bracket I simply bent a piece of steel using the fairing spider as my guide to get the angle required (looking down on it from the top). I then welded both brackets to the two pieces of straight strip that were going to be bolted to the spider. Note that at this point I still don't know where on the spider they will go.

Getting the length of the bracket really was another carefully contrived guessing game but not quite as difficult as it could have been. Once I'd made the fairing infill, I clamped one bracket mount to the spider in approximately the final position using a vise-grip, balanced the headlight in one hand in the fairing cutout and marked the position of the headlight mounting hole on the bracket. It's not quite as Heath Robinson as it sounds (who remembers him? Very Happy ) because if the headlight bracket was clamped in the wrong place on the spider it was either going to push the headlight to one side out of the cutout or there would be a big gap between it and the side of the headlight.

Once one ear was marked, the other one could be measured and marked in the same place. They were drilled and bolted to the headlight. The headlight was offered back up to the cutout with the brackets attached, which gave me the exact position of the straight strips on the top part of the spider (see first pic). I marked the strips for 5mm holes, drilled them, offered the assembly up again and marked the back of the spider for the corresponding holes.

Shaping the strips to meet the bottom of the spider was a vice-and-mallet job. The bottom of the spider is further forward than the top and you can't put a spacer between the strip and the spider because you'll hit it with the lower yoke. Once that was done, all was cut to length, shaped, tidied up, bolted up and treated to a thick coat of Hammerite. Yes, it looks as ugly as sin when you paint over the bolts but it's out of sight and the paint does a good job of sealing the bolts/holes from water.

The relay panel was mounted in the seat hump.

Mounting floodlights on LFB Ch7

It's a new one, not the grew-like-Topsy one of earlier times (Topsy - now who remembers her either!). Of the four relays, one provides power, one does the high/dip and one isolates the spotlights from the high beam. I did this after getting half-blinded by light-scatter in fog. Power is taken directly from the battery. The fourth relay is used to power a fog light and heated grips. Ignore the fact it says fuse 5 - that's on my new wiring loom. To add the heated grip/fog light relay on a standard loom you'll need to find a feed from the black-green wire on the aux power connector in the relay box.

The switch panel is mounted in the leftside fairing strip. The bottom digital gauge is a temperature gauge that lasted all of about eight days... Sad  The other switch (the one without a repeater) is a dimmer switch for the fuel lights in the instrument panel.

Mounting floodlights on LFB Ch6

Finally, the wiring diagram. I'm a fan of topographical wiring diagrams, rather than those that try to show where on the bike the wires actually run. I find them cleaner, neater and a lot easier to read. The only things I needed to pick up from the original wiring loom was the lights-on feed (yellow-and-white on a standard loom but violet on the diagram) and the high-beam (white). Both of these I got from the lefthand switch connector.

Mounting floodlights on LFB Brick3
I hope this makes sense!


__________________________________________________
1983 K100 upgraded to K100RS spec, 1987 K100RT
Others...
1978 Moto Guzzi 850-T3, 1979 Moto Guzzi 850-T3 California,1993 Moto Guzzi 1100ie California
2020 Royal Enfield Bullet 500
    

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