Patern R80g/s mudguard - advice please

[Archie's dad]

Morning Chaps.... just taken delivery of a replacement front mudguard for my 80g/s and I must say it seems a bit crap. It's black plastic with a fair bit of flex in it and is made by SIEBENROCK. My worry is that when I get it sprayed the paint will crack with the flexing. Bought it from Motobins with some other bits cos they were slightly cheaper than Motoworks. However, having just looked on the motoworks website again they describe theirs as...

"Unavailable from BMW. Improved remake. Visually identical but made from glass reinforced plastic for rigidity and strength. Neutral black for painting."

Has anyone got experience of either of these??

Thanks

 

[Beemerboff]

Your description sounds like the OEM one which I removed to fit a shorter one to a tubular lower brace, flimsy twisted with cracked and peeling paint , so sounds like yours is a very good match for OEM.
If you want Siebenrock stuff best to buy it direct from them.
I think the wording on Motorworks site comes from the Siebenrock site so in theory they should all be the same. But----.
I just recently bought a flyscreen from Siebenrock and the quality while adequate was not particularly impressive, compared with what I have seen on other bikes, so someone must be making better stuff than Siebenrock, but I dont know who!

 

[Steve R]

The Siebenrock one will probably be injection moulded plastic and the flexibility it displays is related to the toughness it has when your bike falls over. I wouldn't waste time with a fibreglass one. Yes, it's stiffer but when your bike falls over it'll crack and splinter. The original was injection moulded and I'd trust Siebenrock (they're German) to reproduce it correctly. Look underneath and you'll find some moulded in detail like a serial number, date or little round circles where the ejector pins push it out of the mould. Any reputable paint shop can paint it with flexible paint that will not crack when the mudguard flexes. You bought the right one.

Steve.

 

[ianboydsnr]

Morning Chaps.... just taken delivery of a replacement front mudguard for my 80g/s and I must say it seems a bit crap. It's black plastic with a fair bit of flex in it and is made by SIEBENROCK. My worry is that when I get it sprayed the paint will crack with the flexing. Bought it from Motobins with some other bits cos they were slightly cheaper than Motoworks. However, having just looked on the motoworks website again they describe theirs as...

"Unavailable from BMW. Improved remake. Visually identical but made from glass reinforced plastic for rigidity and strength. Neutral black for painting."

Has anyone got experience of either of these??

Thanks

Sounds about as crap and flexible as the original, don't motorworks make a strengthener to fit?

 

[Steve R]

Look at any mudguard on virtually any motocross or enduro bike since the early seventies and you'll see it's 'flexible' plastic that's injection moulded. There's nothing wrong with flexible. It's a quality of that type of plastic that's associated with toughness. When you fall over, you want it to bend.

Having said that, Touratech used to make a strengthener for the original R80G/S front mudguard that's probably not available any more. It was one of their first products. It was made from recycled titanium surgical instruments from the early heart transplant operations. In 1985 I think they were about £450.

Steve.

 

[Archie's dad]

Thanks for the replies so far. It is indeed mounded plastic. The original was pretty rigid fibreglass with little to no flex. The fact that this one won't break if the bike goes over is of little to no relevance to me as it won't be going off Road and, as I've never 'binned' a bike in 30 odd years, I don't intend to start now (no doubt that statement will come back to haunt me!!). What is pleasing to discover is that if the correct paint is used then it won't crack. I imagine that where the mudguard is mounted, up high on the forks, it will be subject to a fair bit of air resistance. I ain't intending to break any land speed records on the old bike but I don't want it to buckle if I hit 60!!

 

[PW Cymru]

I've got the Fibregalass version on mine andit's pretty rigid.

Haven't had it painted yet though.

 

[Steve R]

Thanks for the replies so far. It is indeed mounded plastic. The original was pretty rigid fibreglass with little to no flex. The fact that this one won't break if the bike goes over is of little to no relevance to me as it won't be going off Road and, as I've never 'binned' a bike in 30 odd years, I don't intend to start now (no doubt that statement will come back to haunt me!!). What is pleasing to discover is that if the correct paint is used then it won't crack. I imagine that where the mudguard is mounted, up high on the forks, it will be subject to a fair bit of air resistance. I ain't intending to break any land speed records on the old bike but I don't want it to buckle if I hit 60!!

It won't buckle. An Acerbic or UFO enduro one might as they're not designed to go 100mph, but a standard R80G/S front mudguard will withstand 100mph. Don't ask me how I know.

Steve.

 

[solidstate100]

Relax. It will be fine, about as good as the original, maybe a bit better. And if you want the OEM look, its the only way to go (unless you want to pay an extremely large amount of money for a NOS OEM one, if you can find it.)

Modern paints will withstand the flexing, unlke the original OEM paint, which ALWAYS splintered and cracked.

 

[Archie's dad]

Thanks

 

[ChasF]

The moulded plastic OEM mudguard on my 100GS is the only plastic part that isn't black plastic painted white. It is flexible but not so flexible that it bends at speed. The mudguard that came on my 80G/S was a big wide thing in very faded red so I assume painted but the paint hadn't cracked or crazed. I've no idea if it was fibreglass or plastic. The UFO vintage one is good quality, not dissimilar to the original and doesn't need painting.

 

[markjackson]

It sounds exactly the same as mine, Siebenrock from 'Bins or 'Works. Nice 'n flexy for when I fall off.

I had it sprayed by a good local painter who laughed off my cracking paint concerns by pointing out how much of a modern car is quite flexy plastic, with paint on. He also tried to explain something to do with paint and lacquer types but… etc.

Anyway, the only missing paint so far (early days tho) is under the washers beneath it and a tiny bit where my juggling skills were inadequate.

The BMW paint on the Calamari was not perfect, so I'd say that yours will probably be better that OE.