Harley Davidson V-Rod Forum banner

1 - 20 of 223 Posts

·
Registered
Joined
·
399 Posts
Discussion Starter · #1 ·
Many riders think that solid rims on a bike cause unwanted problems with stability in crosswinds. That is a myth. OK, take a breath....

Some folks even change out solids and proceed to expound on the great improvement in crosswind handling. It's a placebo effect.

Even a large 21 inch laced wheel is,at road speeds, aerodynamically a solid object as "seen" by the crosswind. If you were riding at 60mph and experienced a 60mph perpendicular gust, you have a crosswind component of 45 degrees or a force equivalent to a 30mph gust at rest,BTW. No matter. The air cannot flow through a rotating wheel in any event. Further,the wetted area of solid wheels vs non solids is very small especially compared to the masive wetted area of the entire bike and rider(s).

Look at the open area of a spoked wheel,including spokes,discs, suspension,etc. As a component of the total vehicle wetted area the disc vs spoked is minimal. It all becomes moot over about 20mph. The spoked wheel generates so much turbulence that there is no airflow through it-it's effectively solid aerodynamically.

This is altogether different on a bicycle! The larger diameter wheels, lower speed and tiny mass and much smaller wetted area compared to even a light motorcycle would make for interesting pedalling in crosswinds. "Solid" discs have been used for racing bicycles. It makes them faster by reducing turbulence-air which has to be displaced by leg power. I think riding bicycles in the wind as kids imprinted our minds later as motorcyclists. Not all bad...

A small airplane propeller with a mere two blades,no rim and no suspension bits around it is over 90% efficient at a typical RPM of 2400 . That same prop,windmilling at 70mph with a dead engine is effectively a SOLID aerodynamic disc which produces drag equal to a disc of the same diameter and reduces glide performance so much that multi engine aircraft employ feathering props-the blades are turned knife edge into the slipstream in the event of a power failure to reduce drag and hopefully keep flying on the remaining,straining powerplant(s). You can see right through a propeller or a spoked wheel when they are turning. Intuitively,they look like open holes for air...

I know it's not an aviaton forum and I'm not dropping bombs but you can see the correlation. The effect of crosswinds on your motorcycle can be dramatic. It is due to the wind acting on the entire bike. The least leverage and wind speed is down low near the exposed part of the wheels. Big windshields, tourpaks and the like or lighter mass/wetted area ratios make things even more exciting. It ain't the solid wheels.
 

·
K.I.A. '07 AW
Joined
·
10,908 Posts
Many riders think that solid rims on a bike cause unwanted problems with stability in crosswinds. That is a myth. OK, take a breath....

Some folks even change out solids and proceed to expound on the great improvement in crosswind handling. It's a placebo effect.

Even a large 21 inch laced wheel is,at road speeds, aerodynamically a solid object as "seen" by the crosswind. If you were riding at 60mph and experienced a 60mph perpendicular gust, you have a crosswind component of 45 degrees or a force equivalent to a 30mph gust at rest,BTW. No matter. The air cannot flow through a rotating wheel in any event. Further,the wetted area of solid wheels vs non solids is very small especially compared to the masive wetted area of the entire bike and rider(s).
must be about 100 threads and 10k posts on this. Hell, I even tried the above physics argument to no avail.
 

·
K.I.A. '07 AW
Joined
·
10,908 Posts

·
Banned
Joined
·
1,521 Posts
You lose!
 

·
Registered
Joined
·
174 Posts
If going from a solid wheel to an open wheel gives the rider more confidence on a blustery day, then that's all that matters...
 

·
V's and Z's
Joined
·
4,093 Posts
It gave me more confidence because it gave me more stability.
 

·
Fah q 2
Joined
·
2,690 Posts
non solid rims weigh less there fore better maneuverability with less rotating mass and gyroscopic effect,
therefore more confidence, and they are better in crosswinds
 

·
In the Shark Tank!!!
Joined
·
1,633 Posts
He must have slept at a Holiday in Express last night....
 

·
K.I.A. '07 AW
Joined
·
10,908 Posts
It's a basic fact; some will never be convinced.:chair:
which one, that all objects act as solid at speed, or that solid wheels increase wobble & sheer?
I frequently ride past a windfarm on my '07 with slotted wheels and have taken a Fatboy with solids down the same course. It does not matter what you are on or in, the wind is gonna push you. I've found every time that if I tuck my elbows in a bit further it GREATLY improved and decreased the amount of wobble and sheer I experienced.
The only time that tucking the elbows does not work is in my car with mag wheels.
 

·
Banned
Joined
·
14,891 Posts
Many riders think that solid rims on a bike cause unwanted problems with stability in crosswinds. That is a myth. OK, take a breath....

Some folks even change out solids and proceed to expound on the great improvement in crosswind handling. It's a placebo effect.

Even a large 21 inch laced wheel is,at road speeds, aerodynamically a solid object as "seen" by the crosswind. If you were riding at 60mph and experienced a 60mph perpendicular gust, you have a crosswind component of 45 degrees or a force equivalent to a 30mph gust at rest,BTW. No matter. The air cannot flow through a rotating wheel in any event. Further,the wetted area of solid wheels vs non solids is very small especially compared to the masive wetted area of the entire bike and rider(s).

Look at the open area of a spoked wheel,including spokes,discs, suspension,etc. As a component of the total vehicle wetted area the disc vs spoked is minimal. It all becomes moot over about 20mph. The spoked wheel generates so much turbulence that there is no airflow through it-it's effectively solid aerodynamically.

This is altogether different on a bicycle! The larger diameter wheels, lower speed and tiny mass and much smaller wetted area compared to even a light motorcycle would make for interesting pedalling in crosswinds. "Solid" discs have been used for racing bicycles. It makes them faster by reducing turbulence-air which has to be displaced by leg power. I think riding bicycles in the wind as kids imprinted our minds later as motorcyclists. Not all bad...

A small airplane propeller with a mere two blades,no rim and no suspension bits around it is over 90% efficient at a typical RPM of 2400 . That same prop,windmilling at 70mph with a dead engine is effectively a SOLID aerodynamic disc which produces drag equal to a disc of the same diameter and reduces glide performance so much that multi engine aircraft employ feathering props-the blades are turned knife edge into the slipstream in the event of a power failure to reduce drag and hopefully keep flying on the remaining,straining powerplant(s). You can see right through a propeller or a spoked wheel when they are turning. Intuitively,they look like open holes for air...

I know it's not an aviaton forum and I'm not dropping bombs but you can see the correlation. The effect of crosswinds on your motorcycle can be dramatic. It is due to the wind acting on the entire bike. The least leverage and wind speed is down low near the exposed part of the wheels. Big windshields, tourpaks and the like or lighter mass/wetted area ratios make things even more exciting. It ain't the solid wheels.

This is an age old topic that will never be settled. And yes at "speed" a cut-out wheel is rotating so damn fast it will react to wind the same way as a solid. I've had solids to spokes on different bikes and get pushed around on windy days regardless of set-up.
*With 80 -85% of "this" bike and rider forming a very large and wide solid mass, with height as well, it's unreasonable to blame a thin 19" wheel that's relatively very low to the ground. But if you need to justify those $2-3000 rims, I get it!

Regarding lightweight wheels as Santeg mentioned, yes, many benefits, weight below the suspension, or unsprung weight loss offers a smoother ride, better handling and better 1/4 times!!!
 

·
Pat (Patrick!)
Joined
·
11,222 Posts

·
Banned
Joined
·
4,421 Posts
remember your parents use to give you the answer..."cause it just is"
or "because i said so":D
 

·
Shelby Stanga Rocks
Joined
·
8,199 Posts
Sounds like the poop hitting the fan on mythbusters. It soilds were worse off in wind then a spoked wheel how come none fall over when the winds blows?
 

·
The Hawk
Joined
·
3,895 Posts
Ok, then I have a couple of questions:

If an airplane propeller is seen as a solid, then how does any air get through it?

Why do solid frisbees fly so much better and react so much more to the wind that a spoked frisbee?

You ever ride a V Rod with solid wheels and get behind a big semi going down the freeway at speed? The effect of those swirling winds on the front solid wheel is noticable in the handlebars and when done with the same bike, same freeway, same situation with open wheels the effect is not there. I think you are oversimplifing the cross wind effect and leaving out the "frisbee effect" on those solid wheels.

Mike
 

·
LIFETIME MEMBER
Joined
·
1,373 Posts
When I get into crosswinds with either spoke or solid, I just turn and go with the wind :).... Seems to work just fine, and I get the added benefit of better gas milage :)...
 

·
day dreaming...
Joined
·
1,795 Posts
spoke wheels are better than solids. They look cooler!

... is it about the looks? I'm confused...
 
1 - 20 of 223 Posts
Top