Looking across to the snow capped alpine mountains seen from the back seat of a motorcycle

Home Repair And Restoration

Envy Screen Extender

Job Date 1 September 2019

By Ren Withnell

Sharon's new screen has been something of a success but not quite a rip-roaring success. As I fully expected it was not tall enough and was causing bad turbulence at higher speeds. I've suffered this myself and fixed this myself in the past.

Finding the correct height is not a science that we mortals without doctorates in fluid dynamics, access to wind tunnels, supercomputer modelling processes and a team of engineers have access to. We mere mortals have to try different things, suck it and see, trial and error. 

An image of a motorcycle with screen and hand drawn swirls to represent air flow
As you can see I am an aero genius.

I did ask if Sharon would let me gaffer tape on some additional plastic to see what is required. This worried her. I explained this bodge was merely experimental, testing, R&D and was not going to be a permanent fixture. No. She was worried about getting the gaffer tape off without ruining her shiny new screen. Dagnammit.

Much like Tour-A-Plank I have to rethink and apply some engineering brain power. 2 strips of slender yet sturdy steel were sourced from the depths of the shed. A hacksaw stroke or 2 were applied. A drill was also pressed into service to make holes and then as if by magic I had "something to try".

A simple digital drawing of 2 strips with holes in them
I created an engineer's drawing with precise measurements.  

I did round off the sharp edges on the bench grinder. I did my best to drill the holes fairly central. However these strips are purely for the purposes of science, of learning and of experimenting. They are not designed to be the final fitting. I expect Sharon will pull her face although I may be allowed to fit them temporarily.

Her Most Imperial Highness casts her critical eyes upon the pieces of metal I humbly offer to her. While I can see she is not exactly impressed she does seem surprisingly open to the idea of me fitting them to her pristine velocipede. My goodness, such honour! I scurry off to the new shed and fit them hurriedly before she changes her mind and punishes me.

The screen on the Kawasaki is about 4 inches higher than the original position
You can see the metal extender in the middle position of 3.

We set out on a dry afternoon with the screen in the lowest of the 3 available positions. After 10 minutes of motorway I am tense with antici... pation! Will she love me and hug me or will she beat me and call me a damn fool? She pulls off the slip road and parks. I wait, nervously.

Her reaction is, well, mildly positive. It is better with less sharp harsh wind noise than before. We adjust the screen to the middle position. It's only an inch higher but these things seem to matter. 

This time the reaction is even more positive. While she is not sat in a serene bubble of tranquil air we seem to have removed the harsh elements of noisy turbulence. I explain that while a screen can remove wind pressure and the worst of the noisy turbulence, she will never achieve perfection. It seems she fully understands this and is happy to accept it. 

In the interest of science we move the screen to the highest setting. A few more motorway miles later the verdict is that it is "no better". In fact it could be worse, she suspects too much air is getting around underneath the screen now. Wow! Without real science we can't be sure but I can see the wisdom in her thinking. We set the screen to the middle setting.

The next weekend sees us both out on the gritty grimy roads of the North-West. After this My Mistress declares the screen to now be "better than satisfactory", high praise indeed, I am honoured. Then something very very strange happenes. Sharon asks me to remove the temporary, suck-it-and-see, research and development, trail and error bits of metal from her beloved and much polished motorcycle - so she can paint them! 

I had of course thought I would be required to seek the assistance of someone who can actually make nice things rather than my bodges. I had thought I'd need to purchase polished steel or anodised alloys. I had thought I'd need a CNC machine. I had expected the final product would need engraving with delicate Japanese flowers and painted with genuine Kwakker Green filigree. 

Sharon sprays the metal with black hammerite paint from the can
My simple handywork recieves the Sharon treatment.

Nope. Sharon slaps on several coats of black Hammerite from a spray can. We purchase some stainless bolts as the Allen hex socket ones are a bit mushy. We put it all back together. We stand back and look. It's not IMMEDIATELY obvious we've been messing and it does not look silly. In fact, in my own humble opinion, I think it looks better. But I have no taste.

The screen is now about 4 inches higher than it was originally
Looks about right that.
Seen from the back we can see hoe the 2 strips of metal raise the screen
It's genius, but it's not rocket science.

What matters is Sharon is happy. As stated she's not in a bubble of tranquil peace but she reports motorway riding is improved with less wind blast and at the same time better than acceptable levels of wind noise. I fear I may have accidentally stumbled into a success. Call the press!!


If you'd like help with technical R&D...contact ren@bikesandtravels.com.

Reader's Comments

Upt'North said :-
Young Ed and Sharon, well done. For an Ed job it looks remarkably stock. And Sharon (who is said to be a little picky at times) is almost impressed.
I believe the final looks have more to with Sharon obviously, but credit where credit is due, Ed has proved himself to be more than a bungling buffoon.
I was wondering what the three holes were for, genius. You could go far Ed, and many of us pray you will.
I hope it still fits in the 5 star accommodation with the high rise screen. That'll be another job.
Well done again, May your journies be wind free and not much turbulence either.
Parp, Parp.
Upt'North.
05/09/2019 19:08:21 UTC
Upt'North said :-
Is this to make ready for the German Frankfurter Riding Frenzy.
Upt'North.
05/09/2019 19:10:07 UTC
CrazyFrog said :-
You're a brave man Mr Ed. I do admire the lateral thought process that resulted in moving the existing screen up rather than extending it though. Well done that man.
05/09/2019 19:34:49 UTC
Ren - The Ed¹ said :-
Good heavens, even the readers are only being marginally cruel? No doubt normal service will be resumed soon enough.

Yes Upt', this is, among other things, prep for our Frankenfurter Riding Frenzy. I do hope you aren't expecting much of this Germanic excursion, we will barely be clipping the edge of Deutschland so please calm yourself. Anyway I'm worried about what Wolfgang and Heidi's (and Francois and Edith's...) attitude will be due to Brexit. I imagine they'll be pointing at us and laughing "Borrreees...ha!"

CrazyFrog. I'm OK at sideways thinking, it's upwards thinking I struggle with. You'll be amazed at what you can do if you're scared enough of The Wrath Of Sharon.


05/09/2019 20:31:54 UTC
ROD said :-
Just a word of warning about the love of screens from one who knows!!! (do I really know anything)???

This love of breezing along in a calm bubble of air at speed will lead to huge touring bikes with adjustable screens.
Once experienced there is no going back...
05/09/2019 21:28:14 UTC
Ren - The Ed¹ said :-
Oh no! Am I doomed to a life behind the perspex barn door of a BMW R-something? Oh well, mustn't grumble I had a fair old crack of the whip.

Sharon!! Pass me a pipe and slippers sweetie, it appears all we can look forward to is comfortable motorcycles.
05/09/2019 22:38:51 UTC
ROD said :-
Just another thought.
Maybe a complete calm bubble of air at speed would be nice, and maybe air conditioning?
Anyone thought of trying a car.
05/09/2019 22:58:09 UTC
Ren - The Ed¹ said :-
Oh I say ROD, what a splendid idea! We could add two wheels to stop the damn things from falling over. Make a roof to keep the rain off. We could put the engine up front so we have space for luggage at the rear, maybe more passengers too. And air-conditioning, that would be lovely, heck what about a heater for wintertime too? Right sign me up.

www.carsandtravels.com...
06/09/2019 08:56:45 UTC
Upt'North said :-
We could all just go out and buy a Goldwing.
Nerrrrrrrrrrr, maybe not.
But they're only £30,000.00 Ed.
Upt'North.
06/09/2019 10:02:11 UTC
Ian Soady said :-
Hi Ren, that actually looks very professional! Haven't we discussed all this at length previously?

I suspect that a lot of the improvement is down to the fact that air can now pass up behind the screen so reducing the eddies you show on your very expert sketch! The same principle as the MRA screen extender and the spacers I fitted to my V-Strom which I think appeared in that previous thread.

History repeats itself, the first as tragedy then as farce (Karl Marx)
06/09/2019 10:13:15 UTC
Upt'North said :-
He may look like an idiot and talk like an idiot, but don't let that fool you.
He really is an idiot.
Groucho Marx.
This could become a long thread.
Outside of a dog a book is a man's best friend. Inside of a dog it's too dark to read.
Groucho Marx.
I didn't start the quotes Ed, it was Ian not me, oh no.
Upt'North.

06/09/2019 11:34:31 UTC
Borsuk said :-
Just to keep Ren happy and resume normal service, Ren you are not a bungling buffoon but merely a buffoon.
Actually I think it looks very good.
Well done that man.

Have a bit of random cruelty.
Spanish weather today is really bad.
Posted Image
06/09/2019 11:44:00 UTC
Upt'North said :-
Borsuk,
That looks a good riding day....presently 60 but feels like 48,light rain and 31 mph winds from the SW.
You've convinced me, I'm riding in Spain next September. Sod the expense. Although I might be tempted to catch the Santander ferry this time and not the Amsterdam one.
No I didn't get lost.
Upt'North.
06/09/2019 12:11:44 UTC
Pocketpete said :-
It's just no cricket....

Come on the ren bodge isnt right it looks to good for rens work.

He's been replaced by an alien or something.
06/09/2019 20:31:45 UTC
Ren - The Ed¹ said :-
"presently 60 but feels like 48" What the devil are you talking about Upt? Are you using them there imperial measurements? At 60 degrees I think most of the UK would simply melt.

Ian - yes it's been discussed much here. And yes this is very much a farce. If you were hoping for a slick professional website with peer reviewed science I fear you may be rather disappointed. Fair point on the gap, I was stunned at how much difference it makes with my 500.

As for being an idiot Upt' and quotes - "It takes one to know one".

Thanks Borsuk, for nothing. Again. Git.

Pocketpete - my success was purely accidental. I stumbled into greatness.
06/09/2019 21:02:20 UTC

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