Category Archives: Plastics

ST1100 Lights, Clocks & Fairing

ST1100 P3 X07 ed After

Part of the redesign started in 2012 was to get rid of this modified Triumph Tiger front panel. I thought it looked great when I first finished it, but now it seems to look too much like the old Avon fairings that the police and AA used on their BSAs, available today on eBay for 99p. Replacing it with an off-the-shelf supermoto/streetfighter fairing would look silly – just a cop-out. I tried a traditional round headlight as originally intended, but it looked a bit boring. It would also mean having to make a decent-looking mount for the instruments and fix up a fly screen for a bit of wind protection.

By late 2015, in the interests of getting the bike back on the road as soon as possible, I decided to stick with the Triumph fairing. This would conveniently hide and protect the original instruments which I want to retain – mileage of 71k is to be proud of! Having lopped off the panel’s side bulges to slim it down, the brackets I’d originally made to hold the lights in and mount the fairing were lost. Here it’s just taped in place:

ST1100 P4 J01 Front

New brackets to connect the panel with the Suzuki GSXR lights were made from 3mm aluminium and held in place with filler as before. The brackets had holes drilled for the filler to ooze through and secure them. Tidying and painting yet to be done:

ST1100 P4 J04 Front

The fairing looked better when closer to the forks and lower down than before – this meant the clock housing would have to be cut down to remove the projecting mounting points (and make it look less like a car dashboard).

ST1100 P4 J06 Front

More home-made 3mm aluminium brackets bolted to the fork clamps now hold the fairing on. It needed another pair of brackets at the bottom of the fairing to steady it (not yet fitted in this picture). The untidy sides of the cut-down clock housing can be seen, needing some sort of disguise – yet to be devised.

ST1100 P4 J07 Front

The removal for the clock housing mounting points meant it needed a mounting plate, which could bolt to the existing tapped holes in the top yoke. I cut this from more 3mm aluminium, with holes for the speedo drive and clock lights, then carefully bent it round a curved former – in the wrong direction. Having hammered it flat again, I could not quite replicate the nice curves I’d got the first time, but it does the job, and won’t be visible normally. I just hope the re-bending has not weakened the metal too much.

ST1100 P4 J08 Front

The original warning light unit was too large to fit between the clocks and the modified fairing, so I decided to try LEDs – 10mm diameter 12 volt units that light up in various colours. The panel is made from 2mm polystyrene sheet, glued together with MEK solvent. Two brackets bent up from scrap steel are glued to the sides with Araldite. These locate it on the front of the clock housing using the screws that retain the perspex cover. I found it best to drill the 10mm holes for the LEDs slightly under-size and finish them with a file, to ensure they lined up neatly. Strips of copper-surfaced printed circuit board (PCB) connect up the common leads (3 needed to go to negative, 4 to positive, just to make matters more interesting). The non-common leads are soldered to a strip of PCB with the copper coating cut through to separate them. The wires cut from the from the old warning lights could then be soldered to the appropriate bits of PCB without putting any strain on the LED leads.

ST1100 P4 J10 Front

The LEDs were held in place quite well by their leads, but a few blobs of Araldite added after this picture made them more secure. Once I’m happy with the unit I will probably box it in to give it a bit more protection. They appear very bright in the relative gloom of the garage, and may need some smoked perspex over them.

ST1100 P4 J12 Front

The speedometer is installed to check that the speedo drive cable run is clear. It will have to come out again to finally bolt the housing in place, with M5 bolts through the base of the housing and the bracket. There is a slight crack in the perspex cover at the bottom of the rev counter aperture. There used to be two small lugs on the back of the cover and housing with screws holding them together. I used these to attach the housing to the top yoke in the previous incarnation, causing the crack – a regrettable bodge!

Painting will have to wait for warmer, drier, weather.

PC800 Side Panels

The bike needed some side panels – it arrived without any, and the spares bike did not have any either.

PC800 P1 A04 Before

I wanted side panels to resemble those on a Gold Wing GL1100, but I happened to have some spare ones from an ST1100. Holding the right-hand one up against the PC800 it looked as if, with a bit of work, they could be made to fit. The bulge at the back neatly fitted round the battery, and the general shape was OK if cut down. It needed to have a V shape cut out at the front to make the top edge fit round the front of the seat, which just happened to align the mounting spigot on the back of the panel with a locating hole on the dummy tank cover.

PC800 P1 G02 Panels

The ABS plastic was quite easily welded back together with a soldering iron, but needed reinforcing at the back with a bit of the cut-off section glued across the join with car body filler. With a few saw cuts and some heat from a hot air gun, the panel could be bent round at the back to wrap round the battery and keep the terminals dry. The panel also had to be heat-shaped a bit at the front to get it to align with the dummy tank. Plastic welding and filler took care of the saw cuts.

 PC800 P1 G04 Panels

Some offcuts and filler complete the transformation. I used car body filler to build up the surface over an ABS offcut to cover the large hole, then bumper filler (finer grain) and finally knifing putty (the white stuff) to fill in small pits and scratches. A bracket made from aluminium strip and glued on to the back of the panel at the bottom fixes it to a handy bolt on the frame where the pillion footrest used to go.

PC800 P1 G06 Panels

A coat of primer showed up some remaining imperfections.

PC800 P1 G08 Panels

More filler, several coats of primer and some black to finish off left it looking reasonable. The process was the same for the other side, just a slightly different shape. This photo flatters – there are still a few bumps and dips in the panel surface. One day, I might replace them with something nicer, but with the ST1100 project dragging on I was keen to get this bike on the road.

PC800 P1 X06 After

PC800 Vetter Fairing

PC800 P1 C30 Fairing

Although I already had a Vetter Windjammer in fairly good condition, I couldn’t resist buying a second one on Bay at 99p. This was black and without lower sections, a bit rough but with a good windscreen. I thought it would be useful for experimenting with, trying out ways to fit a Vetter to a PC800. The chrome plated trim was badly corroded so I discarded it.

With it propped up in front of the bike on some bits of wood on top of an old paraffin stove, the first obstacle to fitting it was the thermostat housing on the right of the bike. Now would have been a good time to stand back and mull over alternative positions for the thermostat, but with enthusiasm unleashed I set about the inner panels of the fairing with an electric jig-saw. The fairing is made of ABS or similar plastic, which fuses back together behind the saw blade unless it’s done slowly so as not to generate any heat.

To get the fairing to sit at the right angle to the bike (with the base tilted about 7 degrees up at the front, according to examples on the Vetter website), I cut a couple of wooden wedges and screwed them to the base. A few more bits of wood raised the fairing to about the right height.

PC800 P1 C02 Fairing

With a hole cut for the thermostat, the mirror mounts either side of the fairing subframe were now in the way. I cut holes in the inner panel for them to go through, but it was clear that the outer parts of those mirror mounts would have to go. I retained as much as possible in case they came in useful for attaching the fairing to.

PC800 P1 C14 Fairing

The headlight bracket that projected at the front of the subframe also had to go, as it hit the rear of the headlight bowl in the fairing.

PC800 P1 C10 Fairing

The hose from the radiator to the thermostat was in the way, so I took it off, a problem to resolve later. The front cross-bar of the subframe still prevented the fairing from going as far back as I wanted:

PC800 P1 C06 Fairing

Having got nearly there, I decided to cut away as much of the subframe as necessary, and hope my welding skills wouldb e up to the job of making it good – I would have to weld on brackets for the fairing anyway.

After much hacking away at the fairing and subframe, it finally sat in the right place. I’d cut away a lot more of the fairing inner than necessary in my attempts to retain most of the subframe, but I decided to keep this Vetter on the bike, and patched up the inside with some of the bits cut off, using a soldering iron. Luckily most of the repairs are hidden. Modifying the other Vetter more carefully could wait until I had nothing better to do. Meanwhile, there was a subframe to fix up, a radiator hose to sort out, and the rest of the bike to do.

PC800 P1 C12 Fairing