Topic: Cross Winds

[ofreen]

Yesterday I rode home into the face of a rising thunderstorm which eventually dumped a bunch of rain.

Thunderstorms are nothing to mess with on a bike.  I say this having ridden under who knows how many and come out the other side thinking that was a real dumb ass thing to do.  (In the spring of 1998 I unknowingly rode between two tornadoes on the R100GS.  I knew something was going on what with all the rain and wind and not being able to see #$%*, but I didn't want to stop.  I found about the tornadoes when I got home, it was all over the TV.)  The rain, hail, lightning and low visibilities are bad enough.  But at least you can see those.  The real hazard is the wind.  Gust fronts, microbursts and outflow winds can hit you like a hammer, coming from out of nowhere and completely unexpected.  The prudent thing to do is find some cover and wait them out.  Every year I try to follow my own sage advice.

[Hush]

I ain't going near this thread after the week I just had on the 650.

[tortelvis]

I also have a Harley with solid wheels front and rear (Fatboy) and you really do not want to ride that bike in a cross wind! Heavy as it is it gets blown all over the road, not fun!

[TwoTired]

I also have a Harley with solid wheels front and rear (Fatboy) and you really do not want to ride that bike in a cross wind! Heavy as it is it gets blown all over the road, not fun!

It would be an interesting science experiment to leave the rear solid and put spokes on the front.  Could act like a weather vane or rudder and steer into crosswinds.  Of course, if it weather-vaned too much, steering would still be "strange".

Sail boaters, pilots, or anyone who plays with machines in the wind will understand this.  Cross wind landings tax your skills. 

[Hush]

Hmm never thought about the mags on the 650, I guess they would catch more wind than spokes, another stroke against the old patrol bikes.

[TwoTired]

Hmm never thought about the mags on the 650, I guess they would catch more wind than spokes, another stroke against the old patrol bikes.

Er, solid mags don't have spokes and don't let any air through them cross-wise.  I wouldn't expect spoke mags to have such an issue.

Cheers,

[Xnavylfr]

I've ridden in MANY heavy thunderstorms in west TEXAS or I'll say try to outrun them. ON any MC with a lot of cross section, wind resistence about the only thing you can do to help is duck and tuck . Duck your head and tuck your body as close to the tank as possible, this will remove  some of the SAIL area sticking up in the wind to blow around. Fairings and windsheilds help for 1 thing, going directly into the wind and fork mounted are worst than frame mounted.
LEARN YOUR LIMITATIONS, if the wind is bad enough to blow you cross 2 lanes I'd call it time for coffee!!!

Xnavylfr(CHUCK)

[HondaMan]

Here in NZ we have just had about 2 weeks of gusty winds and my daily commute into the city for work on my fully-faired Triumph in 40 to 50mph gusts did get uncomfortable...bordering on a bit nervy. However I find the CB750 to be worse....maybe the riding height and the higher centre of gravity make it so?

The big trucks can be as much a threat coming at you from the other direction in big winds...they blow over...at least they seem to over here.

Interesting comments, all: I may have some helpful advice on this topic.

Here in CO, 100+ MPH winds are not at all uncommon. Neither are dead-still days, but most of the time it is more windy than not, usually around 30-40 MPH along the foothills where I mostly ride. Years ago, I found that adding a good, aerodynamic frame-mounted fairing did wonders for high-wind riding. I've been behind my Vetter ever since, and if it were wiped off in a wreck (like my first one was in 1972) I would be on eBay the next day to find another.

Mostly, the 750/500/550/650 bikes are good in the wind, with the least stable in stock condition being the ones with worn tires (flat in the middle) and loose steering head bearings and swingarm bushings. In almost every situation where someone has come to me for this "chassis tune-up" of tapered steering bearings and tightly machined swingarm bushings, they have also come back to comment on how much more stable the bike is in these high winds here. I'm also a great proponent of the rounder profile tires (not like the K70 or Avon Roadrunner profiles) for these bikes. In addition, the CB750 SOHC4 after September of 1969 has a front wheel offset, about 3.5mm to the side opposite the disc, which does not help: re-truing your wheel back to center will add a more stable footing under your seat on these bikes.

[Hush]

I'm not so sure TT, they appear to take up 25% of the wheel so some wind resistance maybe!
Mostly my problem has been the straight up and down screen which is how the cops have them, couldn't change that without altering the "look" so stuck with that unfortunately.

[wardenerd]

Hondaman I used to go to Denver often in my old life.  We would play golf and once a 90 MPH wind blew through.  My buddy from Alabama said that where we come from we give wind like that a name.  Here you just play through.

[heffay]

I think a major issue that people are not taking into account is that we're talking about CROSS WINDS.  A fully faired bike is like a sail from the side, a non fully faired bike is LESS of a sail from the side.  We're only talking about cross winds.  Fairings are to help cut through the wind will going forward... not sideways.

I'm not so sure TT, they appear to take up 25% of the wheel so some wind resistance maybe!
Mostly my problem has been the straight up and down screen which is how the cops have them, couldn't change that without altering the "look" so stuck with that unfortunately.

Agreed, Hush.  TT seems to be contradicting himself saying all the little extra bits here and there add resistance, now he's essentially taking that back.  If there is more mass than regular spokes, then they are going to have more effect than regular spokes... that's my theory, and TT's initial theory.   

[Rigid]

Ninja weighs 138Kg, CB750 weighs 240 Kg.  Almost twice as heavy for the CB.  Ninja also has a large amount of fairing area higher on the bike.  This applies a larger moment to the rotation axis from wind forces.  Poor comparison RR.

[TwoTired]

I'm not so sure TT, they appear to take up 25% of the wheel so some wind resistance maybe!
Mostly my problem has been the straight up and down screen which is how the cops have them, couldn't change that without altering the "look" so stuck with that unfortunately.

Agreed, Hush.  TT seems to be contradicting himself saying all the little extra bits here and there add resistance, now he's essentially taking that back.  If there is more mass than regular spokes, then they are going to have more effect than regular spokes... that's my theory, and TT's initial theory.   

Wire spoke wheels still have a cross section component, as there are 40 of them, and they are not an aerodynamic shape.  Stack them all side by side and they will be 2-4 inches wide.  Wind will exert a force on them, too.

I wonder if Hush understands the earlier commenter's reference to solid mag construction.  They have NO slots at all for air to pass through, making air deflection take a good long route to get passed it.  And, while it is being deflected/diverted, it is exerting pressure on the entire mass.  It's is even cup shape, making airflow around it even more problematic.  Lay it on it's side and it will hold water.  Where wind is concerned, shape matters.  And, I know of no "layman's course" for aerodynamic education.  What, I've learned about it, just makes me realize how complex it is/can be.  Definitive answers are stated in a language quite foreign within a forum which is a collection of personal opinions/anecdotes.

As for Hush's police bike.  The windshield was more for keeping bug stains off the uniform than for any aerodynamic reason.  And on top of that, it was first purchased from the lowest bidder by an accountant.  Can we really be surprised at the technical inferiority?

Riding in or playing in the wind is an acquired skill.  Certainly the machine design can be a factor in capability.  But, it can also be the rider that is simply unprepared.  I'm reminded of the saying; "It is a poor musician that blames his instrument".
Which, I'm told is a variant of "A bad workman blames his tools", which is a very ancient proverb. According to the Oxford Dictionary of Proverbs, the oldest known version is in 13th-century French: "mauves ouvriers ne trovera ja bon hostill" (literally, "a bad workman will never find a good tool").

Don't take this personally Hush.  As I haven't ridden your bike or have any knowledge of your wind encountering skill level.  It's just an observation, is all.  Perhaps your police bike is the worst bike on this earth?  Would certainly be a good reason to sell it off. 

Cheers,

[nancy]

Yes the solid wheels on the likes of the Hayley Doodoo V-Rod etc is a double dumb idea for areas apart from the inside of tunnels. One of my mates has one - he previously had a spoked wheel hayley...but now with the V-Rod..he only goes riding on calm days...

I am more convinced that the fairings may cause more instabilty and that the fairings may NOT cause more instability. All depends on how clever the design. e.g. with an aircraft wing - the rush of oncoming air deflects over the top to create the lower pressure area giving lift. So,..why can't a similarly smart bike designer make the fairing so that side and head winds cause the fairing to have low pressure area below the fairing or lower on the fairing and have a swirling pigs breakfast of a windmass on the upper,..causing the bike to bear down and (figuratively speaking) bike into the road more?

Regards
mark

[TwoTired]

I am more convinced that the fairings may cause more instabilty and that the fairings may NOT cause more instability. All depends on how clever the design.

Quite so.  And there is also the fitting-it-on-correctly aspect.
"Fairings" and "windshields" fall into the same category as "motorcycles", "ignition systems", and "pod filters", in the "general description" regard.

Just do a google search on "fairings" or "windshields".

Nice to have simple categories.  Unfortunately, not all solutions or problem causes are simple.

[Retro Rocket]

Ninja weighs 138Kg, CB750 weighs 240 Kg.  Almost twice as heavy for the CB.  Ninja also has a large amount of fairing area higher on the bike.  This applies a larger moment to the rotation axis from wind forces.  Poor comparison RR.

The parrot has chimed in again, You find me a GPX {Ninja} 750 {220 KG} or 250 that weighs 138 kilo and i'll eat my hat.... The 250 is much lighter but if you read all the posts you would see both comparisons, My GSXR1100 was slightly worse than the 750 ninja as it had a larger covered area and was slightly lighter. The point {which you never took into consideration} is that a side wind has a bigger effect on bikes with full fairings.... Also in your haste to make a complete fool of yourself you forgot to mention that that is also a "dry weight" figure.... Wet weight was 142 kg plus fuel and with an 18 liter tank thats closer to 160kg with a full tank. Once again, you have nothing to offer but trivial rubbish. 

[fatmatt650]

Perhaps some fairing designs are better than others? Is that possible?

Absolutely!

Must be some explanation as to why my K2 is badder in the wind than my Sprint???

My 550 is better in the wind with the Jammer on it, too.

When we rode the rally together you had a Quicksilver on. How would you compare the Quicksilver to the Windjammer. Have you had both of these in crosswinds? I'd assume the quicksilver would provide a lower cross section and therefore be better but the added mass of the jammer might hold to the road better. Does the quicksilver mount to the frame?

Anyone have any experience w/ the Dunstall ajsm2 fairing that Airtech sells. I really want a Don Vesco Rabid Transit but can't find one anywhere and the Dunstall looks pretty similar.

[TwoTired]

When we rode the rally together you had a Quicksilver on. How would you compare the Quicksilver to the Windjammer. Have you had both of these in crosswinds? I'd assume the quicksilver would provide a lower cross section and therefore be better but the added mass of the jammer might hold to the road better. Does the quicksilver mount to the frame?

The Quicksilver is frame mounted.  It was also designed by Craig Vetter, who put quite a bit of thought and testing into his fairings. I've not had the Quicksilver in as severe cross winds as the bigger Windjammer.  But judging by the side loads created by passing big rigs (or being passed by) on the highway, it does pretty well.  Being smaller, there isn't as much buffet protection from the big rigs.
I rode with the jammer all-weather since the early eighties.  I didn't get the Quicksilver 'til the mid 90's, and by then I was rotating through 5 different bikes on my commute routes.

I think the Quicksilver is a better fit on the CB550.  But, for all weather cross country duty, I'll easily pick the Windjammer, especially with lowers, (that the Quicksilver doesn't have).  I still quite like the Quicksilver much better than I had expected.  It came with extra deflectors that fit to the top of the body.  They add about three inches in body height and promise extra shielding.  However, they were missing essential mount hardware, so I didn't leave them on.  They would probably help for "winterizing".  I do have the hardware, now.  Just haven't tried them.

Both these fairings are more about wind deflection rather than stoppage.  A glancing blow imparts less energy than catching it full force.

I dunno, maybe this isn't any help??

Cheers,

[Hush]

All good TT, I know quite a few ex cops who actually rode the CB650PZ and many other cop bikes which we used in New Zealand over the years. The 650 was retired when a cop flipped his end over end and across lanes on the Auckland Harbour bridge back in 1983, they gave a 650 to one of our top race riders of the time and he ran it around the Pukekohe race circuit, after a few laps he removed the screen and commented that it was much improved then after a few more laps he removed the twin pannier bags saying that now the bike handled reasonably well. This brought it back to stock CB650Z really so what he was saying was without all that Police junk on it the bike worked. Shortly after this all CB650PZ's were retired and they moved onto the FJ750 Yamaha which was also rubbish! The ST1100 Honda was one of the best bikes our cops ever got according to the cops I know who had them, at present our boys get BMW's which are a major leap forward in technology and safety. Was my CB650PZ fun, you betcha.

[nancy]

Hush - have you sold the bike?