Trophy 1200 rear mudguard

The rear mudguard is a large injection moulded highly flexible plastic component. So it can put up with a lot of road rubbish without any trouble at all. It is mounted to the frame by rubber grommets and six steel M6 machine screws running through shouldered sleeves. It is also pop-rivetted to two mild steel brackets that clamp a rubber gator to the swing arm, the lower bracket being attached to the swinging arm with two M8 bolts. 

Releasing two M8 bolts that clamp a rubber gator at the forward
end of the swinging arm

The rivets for the gator were very rusty and the aluminium rivets severely corroded so I drilled them out.

Rubber gator and its mounting brackets
after drilling out the rivets

Drilling out the rivets

Coolant header tank showing sheared
pop rivets and mounting plate

The mudguard is also pop-rivetted to a bracket for the coolant header tank. These rivets had failed, the tank loose on the mudguard. The coolant header tank is held on to the bracket by two long torx headed M6 bolts. These had to be soaked in WD40 for a week before I could ease them out. I couldn't use heat or force for fear of damaging the plastic tank.

Refurbished shouldered sleeves

I refurbished the shouldered sleeves with a wire brush on a drill and then leaving them in a bath of phosphoric acid over night. Then it was a coat of anti-rust primer (I use P45 zinc paint) and a hard top coat (Smoothrite gold in this case as an approximation to the cadmium finish of the originals ... and because I got a big tin of it at a knock-down price). The plastic moulding cleaned up beautifully. There were no problems with rivets that retain the stone shields for the air intakes or the ECU bracket.

The final thing was to sort of the gator brackets. These were so severely rusted (I estimate they'd lost half their thickness) that I decided to make my own replacements from aluminium plate.

I painted them with Hammerite special metals primer and some stuff suitable for galvanized metals.

Riveting the gator to the rear
mudguard with three M4
9.5mm aluminium rivets

Mudguard and gator reassembled

The whole thing pop-riveted back together pretty well though it was a cumbersome thing to juggle the gator, clamp, main moulding, riveting gun and a washer behind it. The result is very pleasing to me.

Trial fixing of additional mud flap to
swinging arm.

Additional mud flap with stainless M8
fixings, new clamp bracket and replacement
lower gator clamp bracket

I added an additional mudflap to protect the lower part of the rear shock and the suspension linkage from road muck from the back wheel.