Africa Twin CRF1000L airflow management

Discussion in 'Japanese polycylindered adventure bikes' started by markbvt, Jul 12, 2016.

  1. markbvt

    markbvt Long timer

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    Okay, update after a 300-mile ride Sunday: it's like a new bike. I hadn't realized how much the stock windshield colored my perception of the whole motorcycle. It was so deeply irritating that it gave me a less than stellar opinion of the Africa Twin in general despite how good the bike is in other ways -- riding it was simply unpleasant. The cut-down screen has changed all that. I found myself liking the bike more on Sunday's ride than I ever have. Thoughts of selling the bike vanished. I'm able to crack open my helmet faceshield for venting without it rumbling and vibrating. I can't express enough how much better it is.

    I'm 6'4", by the way. Street helmet; brand is irrelevant because the helmet did not play a role, the severely turbulent slipstream from the windshield did.

    --mark
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  2. x32792

    x32792 Cracker American

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    6' 1" with 32" inseam, HJC IS-33 II helmet, face shield UP: On my AT test ride, I experienced pulsating helmet buffeting (turbulence) under 60mph. The air flow seemed to be coming from the fairing, funneled by twin radiators, more than from over the top or sides of the windshield. It was hard to ignore.
    #22
  3. Pantah

    Pantah Jiggy Dog Fan Supporter

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    I have given up on any helmet with a sharp chin bar and a peak. I've had an Arai and Shoei aboard a KTM 950A and KTM 690R. Bother were bad enough I removed the peaks. Now I use a regular Shoie RF1200 street helmet and am much happier.
    #23
  4. jantomas

    jantomas Been here awhile

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    I'm 193 and have settled for a Shoei Hornet Adv (new version) which works quite well in clean air. I've so far not been able to solve the buffeting problem with any combination of helmets, screens, spoilers or tilt angles, but will surely let you know when I reach Nirvana. (And not only on a quiet day.) In desperation I did today try the AT naked. It may look weird and won't work well above 100 km/h, in rain, in the cold or with lots of bugs (did I forget something? :)). But the air around my helmet was surprisingly clean, almost like when standing up. In contrast to with windscreens the noise is also lower when I push back on the seat. For challenging terrain or situations I always slide way forwards. But it's not very comfortable when you need to pull forwards to the narrow part of the seat to get out if the worst turbulence. For what it's worth I just wanted to share the naked experience.
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  5. x32792

    x32792 Cracker American

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    Perhaps a geographic problem, I'm here in Central Florida where the heat index has been 100+ degrees for weeks. A closed helmet really doesn't seem to be a very practical option for those of us living in this type of climate. NOTE: I hope someone identifies the source of the turbulence problem and comes up with a fix which does not involve a closed, air conditioned helmet.
    #25
  6. Pantah

    Pantah Jiggy Dog Fan Supporter

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    This reminds me of the KTM 950/990 threads about helmet buffeting. I was an early owner and rode with a Arai dual sport helmet with the peak and the face screen. I quickly removed the peak and rode that way for 4 years. I tried a monster windscreen for awhile and it helped. But then I bought a new helmet and it was so good, I went back to the stock screen. A lot of it has to do with your helmet (in my view). Today I use a helmet designed for sound and buffeting. It is aerodynamic. I am a much happier rider. I think the place for the peak helmets is on a race track, and those are all open face with goggles. I get the 'fashion' but the peak and sharp chin bar are not practical for touring. The peak is intended for a motocross racer to shed roost. It has no real sun visor effect that can't be fixed in other ways. Some of the newest helmets attempt to solve those issues.
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  7. jantomas

    jantomas Been here awhile

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    I'd really like an update from you as we're same height and wear the same helmet. I did today try a very similar solution to the one you recommended, namely stock screen tilted forwards but with a Wunderlich spoiler. I tested a lot of positions for the spoiler. It was windy. And the result was OK. Not great. Had I tried it on a quiet day I would probably have been sold. And had maybe even recommended this solution to others. So please give us an update. Does it really work well in windy conditions, at high speeds, when sitting a bit further back etc.? The Internet is packed with first impressions. :(
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  8. jantomas

    jantomas Been here awhile

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    I read the threads in the orange crush while waiting for my 2012 990. And it made me so pessimistic that I actually ditched the sun shade on my then new Arai xd4. But it has worked ok on quiet days in GC when I regularly go 140 km/h. When it's windy down there, just staying on the road takes so much attention that I'm frankly not sure about the buffeting

    I've tried the AT with an older Arai Tour. It's been giving me buffeting. But in contrast to the xd4/990 combo, it also gave me a lot of whistling when I took the shade off. And I got the same whistling with a new quantum ST Pro with an external sun visor.

    The new Hornet adventure is a lot better in this regard. (It too works better with the shade on, and be aware that you can easily loose the clips if you take it off road side.) And it does help shading a low sun. But like all other helmets I've tried on the AT, including Neotec and C3 Pro, it gives buffeting unless I duck low just behind the screen or spoiler. In quiet air it's OK though. That's why we need thorough testing!
    #28
  9. abj

    abj Adventurer

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    I just bought this piece 'a windscreen adjuster' from a German guy called Batzen (Wolfgang Roth).
    With this piece you have a variable screen height from 2,5cm higher up to 9,5cm heigher. First reviews I read on the net were pretty good. Only costs €79.
    Will fit it onto my bike next week (bike now at dealer) and will write a small review.

    More info on: http://bikersjoy.de/2016/05/batzen-scheibenverstellung-crf1000l-africa-twin/

    Attached Files:

    #29
  10. jantomas

    jantomas Been here awhile

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    What did you use to cut and how did you hold the screen while cutting? I just ruined a Givi Aeroflow this morning... I had another nice naked ride today but keep catching too many bugs and need to carry more clothing.
    #30
  11. dodgierogie

    dodgierogie Been here awhile

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    i have the givi airflow and its awesome,and adjustable,throws air over the top of the helmet
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  12. jantomas

    jantomas Been here awhile

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    Mine wasn't quite so awesome. I tried to cut it down so I could go with a very low screen normally and just keep the top as a back up. But it cracked.

    A note on the exhaust. When riding with a screen I've sometimes felt that the exhaust could add to the low frequency throbbing I've had from turbulence. Telling the two noises apart haven't always been easy, but I've felt that it's been worse when going up hill or acellerating.

    No big wonder though. The exhaust note is loud as I can confirm from having gone naked. And then you also have the very frequent backfiring. For people who would otherwise have burned money on an even noisier aftermarket can, this is surely positive. Not so for me though. I've been thinking that perhaps all that droning and popping can actually be bad for my fragile hearing. Any thoughts out there from fellow sound sensitive forumites?
    #32
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  13. markbvt

    markbvt Long timer

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    I covered the screen with masking tape, drew a line where I wanted to cut, and used a coping saw to make the cut while holding the screen between my legs and steadying it with my left hand.

    --mark
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  14. jantomas

    jantomas Been here awhile

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    Thank you Mark! Tried three different saws on the Givi. The lower part is thicker and possible more brittle than the oem.
    #34
  15. toy4fun

    toy4fun GET out of the way

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    I'm 6 1 with the schuberth ef-1 I put the tall Tourateck screen on and its great below 60mph but gets a lot of buffeting after that. keep in mind the ef-1 has the dual sport sun shield on it.
    #35
  16. spartanman

    spartanman regret minimizer

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    MRA Vario. It works exceptionally well. No buffeting and quiet, helmet shield up or down.
    #36
  17. rally roo

    rally roo Total poser

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    It might be a different material as well; acrylic will often crack/shatter where polycarbonate bends. I'm not sure what the stock screen is but it seems fairly durable.
    #37
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  18. Sapitch

    Sapitch Adventurer

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    I did something really similar, but with a straighter edge.
    I wanted to keep the original width, so i used the same shape than the top without going down at the corners.
    Had it cut 2 times with testing in between.
    Removed about 3-1/2" in total to completely obliterate the shaky head syndrome, and it works !
    I think yours looks better than mine, but i suppose i'll get used to it :D

    Printed a cutting template i made with a CAD software. (PM me if someone wants the PDF)
    Finished with a Dremel, followed by 220 and 600 grit sandpaper.


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    #38
  19. jantomas

    jantomas Been here awhile

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    20160805_152105.jpg 20160805_152339.jpg (Also posted in owners thread. I do have a few thumbs and found it's been pretty messy. Many things can go wrong. Just drilling holes in the right place is difficult since two slightly differently curved things are to be placed on top of each other. If you notice two extra holes it's because I first tried to mount the spoiler on top of the stock screen. If indeed you do want to bet on a convertible solution, the easiest thing would probably be to just chop off the stock screen just above the upper mounts, then decide how short you'd like your "spoiler" to be before drilling holes and attach as described below. If fitted on the inside (recommended), using the two upper mounts only will work well I guess as long as the spoiler isn't too tall.)

    Since the first two test rides in silky still spring weather, we've hardly had anything but disturbed air up here. On such days, going naked has proved to be the best solution. After a lot of experimentation I hope (!) I've found a solution. I got a short power bronze screen cheap and cut it as short as possible. It still gives some protection and going fast isn't a problem. It wasn't very windy today but somewhat turbulent and shifty between rain and sun. And the short screen (see picture below) seemed to give a very noticeable reduction in low frequency thundering or buffeting or whatsitsname. I have also cut off the top of a givi airflow and drilled wholes to fit it in behind the power bronze on the top mounts. (Pictures above.) With winged nuts I can mount it in four minutes. (Seems I can even use the stock fixing set without much need for tools. I do it by turning the rubber nut on the inside. It's easy to grab. And I suspect it will give if I should go over the bars, and as such be safer.) It's hardly any bulk to carry. And it provides enough protection to endure a good shower if leaning forwards. Even the buffeting seems pretty acceptable. So it seems I'm good to go. I'll update and provide details if there's interest. I'm 193 and wear a now beakless Shoei Hornet Adventure (current version) plus foamy earplugs. It's my impression that wearing a balaclava and something around the neck helps with noise reduction.

    I'll add that the short version below is the one I belive will be my default. The power bronze was pretty short even before cutting but buffeted still. I'm sensitive. So I wanted to go as naked as possible without hardware sticking out. Now with the spoiler and my very old rainsuit (having stored it for fifteen years I gave it away only two weeks before buying the AT, but it was given back to me as my beemer friend needed something beemeresque:) I belive I'll be able to go on longer trips. But this is ONLY A FIRST IMPRESSION. 20160805_160042.jpg
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  20. jantomas

    jantomas Been here awhile

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    Second impression:
    There is still some buffeting or rumbling even with the shortest screen. And perhaps only a bit more with the spoiler. So getting rid off the rumbling (almost) completely requires going totally naked. But the most irritating low frequency noise is significantly reduced. And still I do get quite a bit of wind protection. Even without the spoiler the protection is much better than naked. I only get bit of blast at my upper chest and neck which is good for hot days. As I may have mentioned, I find it more natural to sit a bit further back on the wider part of the seat with the now lower screens. That's nice. And the riding sensation feels a bit more direct.

    More generally I think that really good wind and noise protection - at least for a tall rider - is something of a holy grail. Even with an rt1200 with electric windshield, wunderlich spoiler and a shubert c 3 pro helmet, my friend is now dreaming of installing some sort of electronic noise cancelling. It actually struck me while pedalling yesterday that even bicycling (or windsurfing in a gale and a half!) is pretty noisy. I just haven't given it much thought. :)

    But don't hesitate to inform us though if somebody finds a perfect solution for tall riders. Unfortunately first impressions are not sufficiently reliable for others to invest time or money in modding or replacing screens. So keep updating!
    #40