FT: Frame (Twin) Rear mudguard loose

[danno]

I noticed also that one of the bolts at the top of the mudguard at the stay had come loose and the hole was larger
as though the alloy was damaged.
I think the same has happened to the lower one as well.
A bit tricky to repair. May have to add large washers or something.

 

[danno]

There is usually at least one cause of hardware loss at the rear end. The bolts F69 that hold the rear stand must be tight enough on the Thackeray washers to prevent vibration; in other words, snug enough to have to lightly push the stand down. You also need all the reinforcing strips, and an extra transverse one across under the mudguard between the upper eyes of the FT22/4 stays is good insurance. Part no. 808 is often overlooked as well. Note rivets 591 are fitted from the inside then trimmed else they sometimes foul the stand catch. I tend to favour Nyloc or Aerotight nuts where they can't be seen!

This is useful, thanks.
With the Spare Parts List I've managed to figure out what I need. I haven't removed the wheel yet but I can feel the reinforcing strip at the front lower end. Not sure if there's one across FT22/4 though.
The mudguard seems to have been under stress which has caused the large holes and bolts 506 to come out.
There's a 1 cm gap between the frame and the mudguard here so need to figure that out.
It also came away at bolt 839 on the LH side causing a hole in the alloy.

 

[greg brillus]

If the rear guard was moving quite a lot, you might want to check your chain guard, in particular at the front bracket on the upper main lug of the swing arm pivot. If this bolt (1/4 BSF by about 5/8 ths in length) has come loose or fallen out all together then the rear guard will suffer badly. The rear guard is actually supported for and aft via the lifting handle and this is positioned by its attachment to the chain guard. It is these two components that dictate the positioning of the guard, check over the attaching brackets, as these are prone to breaking away from the chain-guard too. Cheers..........Greg.

 

[danno]

If the rear guard was moving quite a lot, you might want to check your chain guard, in particular at the front bracket on the upper main lug of the swing arm pivot. If this bolt (1/4 BSF by about 5/8 ths in length) has come loose or fallen out all together then the rear guard will suffer badly. The rear guard is actually supported for and aft via the lifting handle and this is positioned by its attachment to the chain guard. It is these two components that dictate the positioning of the guard, check over the attaching brackets, as these are prone to breaking away from the chain-guard too. Cheers..........Greg.

Thanks.
The chain guard is loose all right. The rear bolt has come out and the front bolt is loose.
There are so many nuts and bolts on these bikes to keep check on. I think I need to have a
bolt check routine in place.

 

[danno]

Regarding rear wheel removal, I've followed the handbook but I'm unable to slip the chain over the brake cam arm.
This is all that's stopping the wheel coming out.

 

[stu spalding]

I had so much corrosion build up between the stainless mudguard and the hinge that it cracked the hinge. It is no bad idea to sandwich a layer of thin plastic between guard and hinge to prevent this on bikes that are ridden in all weathers. Cheers, Stu.

 

[danno]

It's ok. I have an aftermarket lever type centre stand fitted so I'm not using the original which is stopping the
brake drum rotating enough.
I can see that the cam arm needs to be at the bottom so the chain can slip over.
Just need to remove the original stand.

 

[greg brillus]

Stu's Problem comes from the very active corrosive effect between stainless and alloy, two very dissimilar metals. Like owners of light aircraft who replace all the cad plated steel fasteners with stainless.........Over time, when trying to remove these screws........Oh dear not good....... Ok back to Danno's issues........when assembling all the small fasteners for your rear guard, it is a good idea to trial fit everything for a good fit, then remove each nut one at a time and use a drop of blue Loctite 243 on the thread and re-tighten. This is a medium strength Loctite that will allow easy enough removal in future, but prevent the bolts/nuts vibrating loose. Good luck......Cheers........Greg.

 

[danno]

Stu's Problem comes from the very active corrosive effect between stainless and alloy, two very dissimilar metals. Like owners of light aircraft who replace all the cad plated steel fasteners with stainless.........Over time, when trying to remove these screws........Oh dear not good....... Ok back to Danno's issues........when assembling all the small fasteners for your rear guard, it is a good idea to trial fit everything for a good fit, then remove each nut one at a time and use a drop of blue Loctite 243 on the thread and re-tighten. This is a medium strength Loctite that will allow easy enough removal in future, but prevent the bolts/nuts vibrating loose. Good luck......Cheers........Greg.

Thanks. Yes, I found out about the stainless and alloy active corrosive effect when using stainless bolts for the
mudguard stay on my BMW R60/6.
They go through the alloy fork lowers and one of them is completely seized in. Coppaslip didn't seem to help keep them free either. Maybe this reacts with alloy too.

On the Rapide, I've loosened all bolts securing the mudguard and the upper 506 bolt hole aligns ok but there is
a gap of around 8mm at the lower one. The mudguard won't flex to meet up and there's no sign of a spacer here in the spares list.
The FT22/4 stays also seem to prevent correct alignment as disconnecting these at the top allowed the upper 506 bolt
hole to line up with the lug.
Maybe they've distorted slightly.
Good idea about the Loctite. I'll loosely fit all bolts first and see which ones are out.

 

[greg brillus]

I make up spacers from round aluminium bar about 15 mm in diameter and cut to length. Any load pulling or stretching the guard will cause cracks to form, so try and minimize this as much as you can. Cheers..........Greg.