The roof rails should be lubricated at the factory ?.
Lubricating the rails is covered on the MG service schedule sheet ( see below ).
Operation / clean and lub rails are called for on the first service.
It is line item number 10 on the sheet.
You could try opening the roof fully, then using a dry clean paint brush, brush the debris to the front section, then hoover up the bits.
I would probably go for using a white lithium based spray lub and direct the spray on the running gear and rollers ONLY myself.
This what the dealer will use to lubricate all of the hinge points and the door locks etc.
I use the WD40 spray myself ( don’t use the standard WD40 spray as it is not suitable ).
If the roof has not been used for a couple of months ( over the winter time ) don’t be surprised that when you operate it for the first time in the spring, it is not unusual for the roof to stick at the rear of the front section, then open with a loud thud !.
This is because the rear section of glass, has a weather proof seal on the back edge.
Over time this rubber will completely dry out and it binds at the rear.
I have seen this a couple of times on our 2 year old Trophy.
I have found if you tilt the front section, then ensure the rubber seal is clean, then apply a thin smear of a silicone based grease, along the back edge of the seal.
Now close the roof and then tilt it open and closed a few more times.
When you open it again in a few weeks time it will open without sticking ?.
Works for me at least ?.
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