Random GL sighting

[wolf_walker78]

Been a lot of unlikely things gone on in the world. If you'd said to me that once a goldwing pushed a bicycle with a stick behind a Porsche to 150mph I probably wouldn't have believed it..

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[wingrider]

My guess is that the Wing just gave him the push off til he could spin those pedals himself. Pretty cool!

[Sidecar Bob]

Wow! 240 Km/h on bicycle tires.
Wearing shorts!!

[dontwantapickle]

Sucked along in the giant low pressure area created behind the car.
Talk about being in the draft.

Seems like the record should be top speed for a bicycle assisted by two internal combustion vehicles.

[dontwantapickle]

It looks like his forks are turned around backwards.
I wonder why that was done.

[Sidecar Bob]

That is done to increase the trail for stability at speed. It isn't necessary on most bikes because they don't go fast enough for the trail to have much effect.

[dontwantapickle]

looks to me like flipping the forks around backwards decreased the wheelbase by a couple of inches.
The longer the wheelbase, the more stable a bike is at high speeds.

The shorter the wheelbase, the more twitchier. ( is twitchier a word ??? )

[Sidecar Bob]

AFAK twitchier is a word but it's not longer wheelbase that improves stability at speed it is increased trail (or not decreasing it).

I just learned something: That is what they call "motor paced cycling, in which the "pacer operates a car or motorcycle and the "stayer follows on a bicycle, trying to stay as close as possible to benefit from the draft.

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A "stayer" bicycle has a smaller than normal front wheel to decrease the distance between the cyclist's body and what he is drafting behind. When you decrease the front wheel size the rake (angle between steering axis and ground) increases and the trail decreases, which would definitely make the steering twitchier.
So they reverse the forks, which not only brings the trail back to an acceptable number but lets the stayer get even closer to the pacer.
This image shows a normal bicycle on the left and a stayer bike on the right. Note that the drawings are the same scale (the frame is the same size but the wheel is smaller). As you can see, the trail is close to the same for both but the cyclist will be able to keep his body will be significantly closer to the pacer with the stayer bicycle.

Stayer forks.jpg (27.24 KiB) Viewed 344 times

[dontwantapickle]

Interesting !

[Sidecar Bob]

And after that percolated in the back of my brain overnight I remembered reading this a couple of years ago. It doesn't say much about the bicycles but the motorcycles were very interesting
https://motorcyclemojo.com/2022/05/motor-paced-cycling/

[Old Fogey]

There's a pacer bike in the 'Wheels through time' museum Maggie Valley.

[Lucien Harpress]

Concerning flipping the forks- it's like the front wheels of a shopping cart. They tend to self-correct, which I imagine would help at really high speeds.

I follow a pre-1920s motorcycle group on Facebook, and more often than not these old "pacer" motorcycles keep coming up. They are some WILD machines.

[Sidecar Bob]

The front wheels of a shopping cart are casters. Casters don't have any rake at all and only "self correct" by being pulled along behind their pivot points.

The backwards bicycle forks work more like increasing the rake angle would, but without the need to cut & weld the frame.

[dontwantapickle]

I found this pic of a stayer bike with the forks not reversed. It was obviously done both ways.

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I really can not imagine how reducing the trail would make the bike more stable at higher speeds.

I would venture to guess that the backwards forks and smaller front wheel are to aid in the aerodynamics.
the smaller front wheel gets the rider lower and the shorter wheelbase gets the bike closer to the motorcycle
helping with the draft.

[dontwantapickle]

Don't want to worry about aero ?
Just need to get a dragster to hide behind.

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stayer salt 2.jpg (81.67 KiB) Viewed 114 times

Them is some pretty small wheels on that bike, they had to be spinning some serious rpms at 184 mph..
I bet those bearings were smoking hot when she stopped.