do dubble bubble screens make a difference?

[tmsjns]

Hi i have a little cbr 125 and planning on keeping it for commuting my 50 miles a day, Anyway so Ive seen these double bubble screens, Do they really make a difference? I live in north wales and its pretty winding on the ride to work, Would a double bubble screen help me to not get blasted by the slight breeze?
Im thinking improved aerodynamics means a even better mpg? would a dubble bubble screen help this?
Can anyone suggest a decent one for a 2010 cbr125? airblade? puig?

cheers

[DrDonnyBrago]

On a bike that size, I really doubt it.

Doesn't make a lot of difference on my CBR600f, just kinda pushes the wind a tiny bit higher up my chest. I take it to be because the screen is quite low and narrow, so an extra 4 inch bump does bugger all.

On something with a high and wide screen, like a FJR1300, a modification to the screen is probably a lot more noticeable.

[Polarbear]

Not being a racer, I gather they are for people to tuck down behind which makes sense when you watch moto GP or the like.

I doubt you will notice much difference on a 125 unless you tucked right down. A touring screen might be better for you.
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[tmsjns]

A touring screen, I'll check them out, I was thining it would lift the wind off my chest but if they dont make that much differnece then I wont bother.
Cheers

[Itchy]

Some do some don't had one on my CBR for a week, instead of the wind pushing my chest it now went into my face rotating my neck backwards.

It also whistled annoyingly.

So the old screen went back on for wind against chest.
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[Pete.]

I had a double-bubble with a flip-edge and it was great for deflecting wind and rain over my head. The plain DB does it too but not so well. Anything that pushes wind around your head and torso is good for comfort and fuel consumption generally, though as said above some designs aren't as good at it as others.

My current Bandit, like several of my bikes before, has an old double bubble screen fitted to the clocks and headlight as a wind deflector.
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a.k.a 'Geri'

132.9mph off and walked away. Gear is good, gear is good, gear is very very good

[Dave500]

On a 125 possibly not tbh but it maybe worth a look at a MRA screen they a fantastic
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[wristjob]

wind blast on a 125?
do you fall over if someone opens a window?
are you made of feathers?
but seriously dont waste money on a screen it wont make any difference at the speeds you travel.
i ride a naked bike and yes anything over a hundred feels like you are trying to ride through custard but you get used to it.
spend the money on beer and pies so you get to enjoy it

[Llama-Farmer]

[talkToTheHat]

Surely with less power, better aero will make a bigger difference?
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Bandit. does. everything.

[wristjob]

[Pete.]

Less drag = more speed and less fuel consumption. It always helps.
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a.k.a 'Geri'

132.9mph off and walked away. Gear is good, gear is good, gear is very very good

[Llama-Farmer]

But at such low speeds the parasitic drag is not reduced by a particularly effective amount.

True it makes a bit of a difference, but an inconsequential difference.


At 180-190mph bombing round the IoM then a big screen deflects airflow for the riders to duck down under, it makes an effective difference.

Your average sports bike with your average sports bike rider on your average road might notice a comfort improvement, but fuel and speed will not be noticeably affected.


90% of the time, riding a 125, you won't have the speed to make for an effective aerodynamic flow improvement anyway
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[GrumpyGuts]

After I dropped my ZZR (and breaking the old double bubble windshield) I could not find the seller that sold that type of screen, so I opted for a touring screen.

Don't even bother - it's allowing all the wind to blow right in my face and into my helmet - I can't hear anything past 40 mph
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[Dave70]

I'd just echo what most have already said and say that you wouldn't really notice any benefit from it tbh.

Save your money and either put it towards your test/lessons or wait until you get a bigger bike and fit one to that.

Also, try lying over the tank more on your CBR and sticking your head down if the wind's a problem, as it does make some difference. I ride a R125, which is similar to the CBR and this works for me. It probably doesn't really make you go faster but, can stop the wind buffering you as much.

[talkToTheHat]

Given that the land speed record for a human powered unpaced bike is about 83mph, I think aero is significant with low power outputs.

Significantly, if it takes 14 horsepower to cruise at 70mph and a motorcycle only makes 14 horses, changes in aero drag will be immediately apparent.

If a motorcycle makes 140 horses, it will be difficult to legally explore aero-limited performance, but comfort of aero parts is a significant factor.

A screen at the wrong angle or height for a combination of motorcycle, rider and riding position is not going to be comfortable.
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Bandit. does. everything.

[R_Josh]

[Notj7]

Absolutely. I really miss the double bubble on my old CBR 600F. I could use one on the RR, but it'd look stupid with one on considering how low down the screen is by default.

In fact, I can't even see the speedometer because of the current screen sometimes unless I'm licking the tank
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[Doovy]

I have a tinted double bubble to replace the standard clear it came with on my RR, which is quite low down, and it makes it nicer to tuck into when at speed.

I don't notice any particular change in wind blast when I'm not tucked in, although I was used to a naked Hornet for a while before putting a small screen on that too.

I can't imagine it would help 'much' with fuel efficiancy. I got mine for about £25 off of ebay, not branded, just a generic 'CBR600 RR tinted double bubble screen'. Seller sent me wrong one for the year originally but then sent right one, and I forwarded the incorrect model onto another BCF member.

Here is CBR with me on it, not tucked in.

https://scontent-a.xx.fbcdn.net/hphotos-xpf1/t1.0-9/10259736_623608751049324_3611640661766261307_n.jpg
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[djrikki]

Fitted one to my Yam and its amazing! Best thing ever
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[deadwolf]

[Sload]

Tends to be that double bubbles add more resistance over standard screens so increase drag, but on your bike as stated you would barely notice the difference. On my old vara, it could sit at about 70 and wind blast was more then manageable but I couldnt tuck in on that anyway.

On my Triumph I had a useless screen and no fairing and again up to 70 was comfortable, over that it grew exponentially uncomfortable.

On the CBR I can manage quite well into high figures if I tuck in, but I'm not a shortarse Japanese so I have to squash elbows to thighs tight on the tank with a nasty crank in my neck. I'm thinking of fitting lower pegs and bar risers as well as a double bubble. The different screen will increase drag and reduce the effectiveness of the aero but I doubt I will be sitting at 180 for long stretches anyway. It is all about application.

And your application really wouldnt see a benefit.
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[ADSrox0r]

On a 125, screen doesn't do shit. Period.

[Llama-Farmer]

[Andy9934]

Air resistance increases with the cube of velocity. If you are travelling at 70 you will lose 50% more energy more energy to drag than someone travelling at 60!

Therefore it is more important for faster bikes.
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