MRA Vario or Wunderlich screen (1150GS)

pauly

Guest
I apologise if this subject has been covered many times before, but does anyone have any experience of the MRA Vario screen or the Wunderlich Touring screen, or maybe tried both?
I had a short ride on an 1150 fitted with the Wunderlich but wasn't convinced it was much better than the standard screen.
I'm 6'2 by the way.
Thanks,
Paul
 
Re: I've had both

needlongerlegs said:
Go for the MRA easily the best.
Far less turbalance and ajustable.

I agree. Bit flimsy, but works best of the lot. Something to do with the vented design, doesn't create that low-pressure area behind the screen which seems to create the turbulence.

Steve.
 
Something like "They're like arseholes, everyone has one" ??

Bob Southgate
 
MRA Vario - without doubt - the only adjustable option on the market and the smoked colour looks good too.
 

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Tinted MRA

Funny that, I looked at the Vario but rejected it because it was not available in clear, strange how peoples tatses vary.

It s shame really 'cos the web site says it is available in clear but the dealers all told me it only comes in a tint. I need it clear so I can mount a camera behind it.
 
Bob Southgate said:
Something like "They're like arseholes, everyone has one" ??

Bob Southgate
Yes- and very few bear close inspection
 
Just bought and fitted the MRA screen this afternoon. I took it for a 30 mile run on a wide mix of roads to test it out. The verdict?: Much better than the standard screen. No buffeting, quieter, far superior all round. I have got the top part of the screen on its highest setting, and the whole screen is in the middle position. Seat is on the highest setting. I am 6'3" with a inside leg measurement of 33 inches.

Now, why can't BMW fit a screen that does the job properly at the factory??

Bob Southgate
 
Bob

Can I ask where you bought screen from and how much you paid?

cheers
 
Dave,

I got it at Julian Soper Motorcycles in Leigh on Sea. It was £114. I popped down and got it this afternoon. They are at 1335 London Road, Leigh (which is also the A13) They said they have plenty in stock.

Bob Southgate
 
Thanks for the advice everyone. Most seem to favour the MRA so I think I'll give one of those a go. I'll let you know what I think of it.
 
Pauly,

Nice timing with this thread. I've been ranting on and off about how I always get a soaking wet chin and neck every time it rains, caused (I assume) by the turbulence in this area.

Last week, I'd finally had enough, took Friday off and went down to Wunderlich. I'd originally planned to go for their own brand Touring Screen, since I'd been advised by one BMW Dealer that the problem is the air flow from the side, rather than over the top. The Wunderlich version is approx. 6cm wider than the standard screen.

The guy at Wunderlich advised me that the MRA was the better screen for rain protection, but personally I don't really like the look of it.

At Wunderlich, you can at least test everything. (They have several models of seats and screens for this purpose).

The verdict:

The Wunderlich touring screen appeared to have no significant change in the turbulence under the chin, regargless of the setting.

The MRA showed a drastic improvement. Set in the "backward" (i.e. standard screen "lowest") position, with the top part one from top, there is hardly any turbulence at all. It's much quieter and I like the fact that the top part is adjustable whilst on the move (although I'm sure an Owner's Manual would instruct you otherwise).

So, despite the looks, I bought the MRA. I'm now awaiting rain (I'm sure I won't have to wait long!) for the final test.

BTW, I think this is really a height issue. I'm 5' 7" and use the BMW lower seat. If I stand up a bit, there is a reduction in under-chin turbulence. I'm also considering changing the seat height every time it rains....
 
Dave Barrett said:
BTW, I think this is really a height issue. I'm 5' 7" and use the BMW lower seat. If I stand up a bit, there is a reduction in under-chin turbulence. I'm also considering changing the seat height every time it rains....

Dave (and others with the same problem):
You're spot on and I commented on this a few weeks ago after some wind-testing results from our biomechanics lab at work. Many riders suffering from buffeting/turbulence waste a lot of money trying to buy a taller screen. The people who suffer most are shorter riders with the seat in the low position. The turbulence is created largely round the sides of the lower part of the screen (putting the screen in its most upright position makes it worse) and the airflow is further disturbed by the brake/clutch cylinders, mirrors, and handguards.
If you're short and have the seat set low you get this turbulent air hitting you smack on the chin. Because of my height I don't feel it at all because it hits me across my chest at armpit level.
All screens will create turbulence. There are only three solutions:
(1) remove the screen - more wind pressure but no turbulence and buffeting;
(2) fit a screen wide enough to deflect the air further and move the turbulence behind the rider (but it now effects the pillion) - you might also experience a feeling of being pulled slightly forwards which can become tiring after a while;
(3) fill the space behind the screen with air at an equal or greater pressure to remove the partial vacuum.

Solution 1 is very effective up to about 80mph when it becomes tiring just like it does on all naked bikes.

Solution 2 possibly works for the some of the extra wide Cee Baileys screens which use the Adventure mounts, but it doesn't work for the Wunderlich because the Wunderlich extra width is not at the base where it needs to be. In fact the shape of the Wunderlich possibly exaggerates the amount of turbulence if you're short. Yet it's probably the best solution for somebody about 6' to 6'2".

Solution 3 works for the MRA because of its dual nature - air flows through the screen. One of the best screens ever on any sports bike was the standard screen on the Honda CBR1000 which was one of the first to feature holes/ducts at the base of the screen to produce a wall of air behind the screen and a venturi effect. IMHO what would be better is a screen based on the MRA but without the adjustability (which I think can make it flimsy and unstable according to some reports), just one-piece moulded on the same principle and maybe as wide as the Adventure screen using Adventure mounts.

All of this is specific to each rider as well, their height, seat position, body position, arm length, back curvature. You really have to try before you buy. So, somebody will rave about the Wunderlich screen. Another member will go out and buy one and claim it doesn't solve the problem.

I'm not a physicist so more knowledgable members out there will correct me if my basic fluid mechanics is wrong, but I work with and talk to professional biomechanists every day (mostly concerning airflow around golf balls and cyclists and so on) and it amazes me why bike/screen makers can't apply simple mechanics to develop screens that work instead of relying on the car-windscreen school of design.

Let us know how your MRA copes with the rain!
 
Simon Eassom said:
There are only three solutions:
Actually there is a 4th, but I don't want to stand in a bucket of manure for the next 3 months to see if I can grow a little taller ;)

Seriously, the air flow / vacuum technique has been around for a bit. I first experimented with my olf F650, based on the various suggestions from the FAQ's from the Chain Gang. (which others may also find useful: http://faq.f650.com/FAQs/Buffeting.htm )

What I find really disappointing / frustrating on the 1150 is that BMW went to the trouble of lifting the screen away from the silver backplate to create this vacuum, but it doesn't seem to be very effective if you read all of the threads related to screens.
 
I have a Cee Baileys screen which is +4" taller than standard and +3" wider. It is in its most sloped back position.

It's great up to 50 mph but then it creates the buffeting as bad at + 60 mph as with any other screen. (I must say that because the screen is quite tall and not terribly well supported by the mounts it does wobble a bit).

Intriguingly, I often find as many dead insects on the lower, inner portion of the screen as on the outside, suggesting that air is "sucked" up into the inner screen pretty fast. Yes, I agree that turbulence is probably created by air coming up through the gap between the silver plate and the perspex and by coming round the sides. I suspect additional screen blades on the sides of the screen may help and I'm tempted to experiment with blocking off the gap between the screen and perspex altogether - what do you think chaps ? I'm tempted to cut little slots in the lower half of the screen too. The Cee Baileys screen is deceptively narrower at its mid point that you might think, and this augments the problem.

I agree with Simon's reticence about the MRA although I've no doubt it works. Also, having experienced wind pressure on motorways, I'm not sure it's better than the buffetting.

Discussion much welcomed !!

Alex
 
Airflow etc

Peeps

We must be close to putting this whole subject to bed now. With the help of a 2 large fans, and a dummy with bits of ribbon sitting on Doris, in my garage I was able over the weekend to confirm what has been said here having spent about £400 on screens of one sort or another. At 6ft and a 32"inner leg I need a screen that's laid back like a sports bike. Low and/or wide is fine - e.g. cut down Adv screen or no screen. Tall: definitely not; flipup: definitely not.

Jonnyboxer and others have recommended the MRA. The jury is out on the Wunderlich as noted above. If MRA come up with an Adv screen plus extension bits for the std GS - that will probably do the business. Until they do we will have to accept the situation. Independently, I am going to commission a wide low one in the new year and I'll keep you posted.

Is anybody speaking to MRA about what we want in the way of strength etc?
 
Re: Airflow etc

Mark Dilloway said:
Is anybody speaking to MRA about what we want in the way of strength etc?

Some of the guys on the ADVRider board were submitting their ideas on the MRA to Cee Baileys, but I'm not sure whether they are following it up. An email to Steve at CB might be worth a shot.

www.ceebaileys.com
 
Steve,

Thanks Steve. The CB product is absolutely beautifully made - but I would prefer to use supplier(s) in the EU who can produce a comparable piece of kit so as to avoid the import duty. Having an EU vendor would give people the chance of seeing before handing over their cash.
 
MRA screen for Adv

Having said that I wish to hear no more on this subject I contacted Brigitte at MRA and they expect to produce a screen for the Adv in the New Year. So anybody who knows these people - perhaps our Deutsch comrades - has a real opportunity to influence them to get the design correct.
 


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