Yet another windshield thread (aerodynamics related)

Cascanciu · Post by **Cascanciu** » Thu May 03, 2012 5:47 pm

Hi all:

Not that I'm thinking of fitting a windshield right now, but I wanna make the right choice when the need comes. Temperatures are already mild, so no worries for the moment.

Question is, which one?. I was initially leaning towards the original Honda windshield, but it's priced quite high over here (+150€). I would pay them if it turns out to be the best alternative out there, but there is one more concern... aerodynamics. This windshield leaves a gap between itself and the front panel, where it's mounted. In a Spanish forum I also post at, some guy posted a link of another forum, French one this time (Global Village, you know

) and the French fella said he thought the gap was meant to alleviate turbulences. Some other guys at the Spanish forum reported minor problems with the -short- Givi windshield, in the sense that they noted the bike more sensitive to lateral winds and wind recoil when overtaking heavy vehicles. I wonder if the original Honda one would be more efficient for that matter.

The alternative is the Ermax, either the tall or short version (will have to decide on that). I like the black trim and the darkened finish it has, would fit well my black PCX.

So, is there anyone out there with an original Honda windshield willing to shed some light on this

.

Cheers!.

Edit, I'm 176 cm tall, which should be 5ft 9 more or less.

Woolley · Post by **Woolley** » Thu May 03, 2012 6:12 pm

If it was me I hate the look of any bigger windscreen on the PCX, so I'd be buying purely for comfort so I would get the MAHAHAHAAAASSIVE one that maddiedog has.

jasontheparamedic · Post by **jasontheparamedic** » Thu May 03, 2012 9:14 pm

If you're gonna get a windshield, it's best not to half-ass it if you are wanting practicality. I have a tallest Givi windscreen and it helps. However, it is not the prettiest in the world, but it works.

Taz · Post by **Taz** » Thu May 03, 2012 10:47 pm

Im happy with my ermax +25 (tallest version). Keeps all wind off my chest, gives me a higher top speed and looks OK. Its not as tall as the tall givi but Im 193cm tall and Im satisfied. I posted pics elsewhere on this forum but if you cant find them let me know and I will repost.

gn2 · Post by **gn2** » Fri May 04, 2012 1:45 am

If you want to keep the wind off, get a car.
You're supposed to feel the wind, it's part of the fun of riding.

Cascanciu · Post by **Cascanciu** » Fri May 04, 2012 5:17 am

Well, yeah, I do have a car and agree about the "fun" of the wind, but it's not that funny when you have 4º celsius out there or it's raining, and I plan to ride during winter, too. I got this bike because I was (I am, actually) sick of struggling to find a parking spot or pay to do so.

I saw your picks, Taz, and EddieC's in the same thread. The Ermax looks good, that's why I have her in the "pole position" of my list. With my height, I was wondering if the short one would be enough, but surely the taller one will work better.

Thanks for your inputs

.

gn2 · Post by **gn2** » Fri May 04, 2012 12:18 pm

Cascanciu wrote:it's not that funny when you have 4º celsius out there or it's raining

Doesn't matter what screen you buy, you're still going to get cold and wet.
Better to buy decent cold weather riding gear.
(4º is pretty normal for me and in winter I regularly ride in sub-zero temperatures)

JGC · Post by **JGC** » Fri May 04, 2012 2:59 pm

Well I have just fitted the standard Givi screen tonight. I'll see how I get on with it.
As for gear, I wear a Hi Vis Hein Gerricke fully armoured textile jacket. for trousers I bought a pair of ski trousers from mountain warehouse, and they are good. I do have armoured trousers, but don't wear them because I don't have anywhere secure at work to store my gear (Jackets I take with me on my coach) The combination of gear I have has kept me dry up to now

gn2 · Post by **gn2** » Fri May 04, 2012 3:19 pm

I bought a topbox to store my jacket and gloves in while I'm at work, my helmet and HG Boost armoured trousers fit under the seat.

Cascanciu · Post by **Cascanciu** » Fri May 04, 2012 5:15 pm

gn2 wrote:
Cascanciu wrote:it's not that funny when you have 4º celsius out there or it's raining
Doesn't matter what screen you buy, you're still going to get cold and wet.
Better to buy decent cold weather riding gear.
(4º is pretty normal for me and in winter I regularly ride in sub-zero temperatures)

That's correct, but perhaps the best option is to combine proper riding gear, with the best windshield alternative out there

.

gn2 · Post by **gn2** » Fri May 04, 2012 11:24 pm

No, you want to feel the wind...

Taz · Post by **Taz** » Sat May 05, 2012 4:30 am

This is gn2 on his motorbike when its 2 degrees:
http://photos.imageevent.com/motorbiker ... kilt-2.jpg

but for the rest of us a tall windscreen is a must. The small ermax is only good for looks wont keep the wind off you. If you go ermax go the +25.

TC3 · Post by **TC3** » Sat May 05, 2012 5:01 am

Taz wrote:This is gn2 on his motorbike when its 2 degrees:
http://photos.imageevent.com/motorbiker ... kilt-2.jpg

but for the rest of us a tall windscreen is a must.

I ride in wind and rain on the A1 and have no problems with the stock screen so talk for yourself!

Cascanciu · Post by **Cascanciu** » Sat May 05, 2012 10:19 am

Taz wrote:This is gn2 on his motorbike when its 2 degrees:
http://photos.imageevent.com/motorbiker ... kilt-2.jpg

but for the rest of us a tall windscreen is a must. The small ermax is only good for looks wont keep the wind off you. If you go ermax go the +25.

True, I like the looks of the short one, but I'll end up getting the tall one, most likely.

maddiedog · Post by **maddiedog** » Mon May 07, 2012 9:34 am

I've ridden with both the short Ermax, and the enormous Givi. I'd stick with the Givi.

Going back to aerodynamics, you have a better aerodynamic profile with the larger windshield, because air doesn't blast you directly, it goes over you, forming an eddy current between you and the bike. I think the gap at the front that you mentioned helps route the air internally, assisting in forming the eddy current, and preventing any "chopping" from the air bouncing in then out.

I noticed no difference getting blown around with the stock windscreen vs the short Ermax vs my tall Givi. With the stock windscreen, I experienced full wind blast on my chest, head, and hands. With the short Ermax, I experienced much less wind on my upper chest, but still a full blast of wind on my head and hands. With the tall Givi, there is no wind on my chest, almost no wind on my head, and much less wind on my hands.

Cascanciu · Post by **Cascanciu** » Mon May 07, 2012 4:41 pm

That's one useful opinion, Maddiedog. Makes sense that this gap helps in creating this airflow above the rider's help. Shame that the Honda windshield is SO expensive. Unless I can get a bargain on the net, I think I'd throw the tall Ermax in.

Thank you!

Taz · Post by **Taz** » Sun May 13, 2012 6:27 pm

Ive just taped over the gap in the front of my Ermax +25 to see the affect now I am coming up to winter. I think its the same gap on the stock windscreen too, about 2 inches wide by 10 inches across above the headlights. I was getting helmet noise before and that seems reduced now. Will go home on a fast road to see affect at WOT (wide open throttle).

By not having a gap maybe I can store stuff there now! Before I put a summer gove and it slipped down thru the gap. Will post pics later as iPhone is flat.

Taz · Post by **Taz** » Sun May 13, 2012 10:31 pm

Here is the pic of my temporary patch to the windscreen gap:

IMG_0118 by TazPCX, on Flickr

Helmet noise has been reduced a little but now I am too warm so will remove the tape before summer comes back

Havent had the opportunity to go faster than 45mph yet. Let me know any ideas for a better looking patch. I thought of clear tape but thats usually not UV stable so wouldnt last long. White gaffa tape could be the go.

Woolley · Post by **Woolley** » Mon May 14, 2012 12:50 pm

you could just stuff an old tshirt or towel down the gap.

maddiedog · Post by **maddiedog** » Wed May 16, 2012 12:39 pm

I'm curious how that would affect the wind for 45-55mph, since aerodynamics make a bigger difference at higher speeds. Can you try taking it for a spin a bit faster before removing the tape?

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