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The R18 sidecar thread

  • <i class="fa--xf fal fa-check "><svg xmlns="http://www.w3.org/2000/svg" role="img" aria-hidden="true" ><use href="/data/local/icons/light.svg?v=1776214450#check"></use></svg></i> Discussion starter Discussion starter Petrus
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Today next step dog training:
Him on the terrace when I arrive so he is happy to see the rig because happy to seen me.
Engine running, ex+1 in the chair, him in her arms, let zennnn...
Done.

Hope to de Thursday and Friday next step; a short spin with him on her lap.
Depending on how relaxed, repeat or final step; him solo.

Extra thingy is that he HÁTES aire passing his ears so I will pull a 'sock' over them. On the one hand that annoys him but also distracts.

Earlier I had named the bike 'Dicken Bertha' but it now is not anymore really. As a rig that flag does not cover the crux.
Will have to have a bit of patience; she will show character and choose her name.
 
Petrus said:
Today next step dog training:
Him on the terrace when I arrive so he is happy to see the rig because happy to seen me.
Engine running, ex+1 in the chair, him in her arms, let zennnn...
Done.

Hope to de Thursday and Friday next step; a short spin with him on her lap.
Depending on how relaxed, repeat or final step; him solo.

Extra thingy is that he HÁTES aire passing his ears so I will pull a 'sock' over them. On the one hand that annoys him but also distracts.

Earlier I had named the bike 'Dicken Bertha' but it now is not anymore really. As a rig that flag does not cover the crux.
Will have to have a bit of patience; she will show character and choose her name.
Click to expand...
The Hochstetter….reminds me of Major Hochstetter’s car in Hogan’s Heroes. Big, with lots of presence.
 
BMW being Bavarian going for Bavarian Heidi :p
Now, I missed the tv series but did work several months in Bavaria/Tirol lodging in a local kneipe with the two dirndl named Diana and.... Heidi.
 
Net step training:

Had him running about 'helping' me on the farm and then 2 hours on a terrace

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Then took him to the apartment and after wolfing down food he féll asleep in his basket.
When soundly asleep moved him basket and all into the sidecar, me set next to him in comfy 'smoking chair'. He obviously noticed, 'looked' and decided to continue sleeping.
That should properly imprint being comfortable in the seat.

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1778005740971.png
 
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btw guys, some relativating ponderings:
A classic motorcycle with sidecar; i.e. bolting a sidecar to a stock motorcycle is always going to be an inherently compromised asymmetric concept.
Leading link front fork, suspension mods., sidecar wheel ride height adjustment on the go ('camber adjustment´) etcetera is not going to change the fundamental compromises one single bit, only shift the compromises.
I could go into each of the aforementioned examples if someone wants to understand.

The crux is that trying to improve the concept is akin donning protective pads in a motorcycle jacket in the perspective of a carś protective cage. The concept of the motorcycle means yoú are the crumple zone.
A classic motorcycle with sidecar will always be thát: Think about it for a moment. It is basically the same as the 1890ś pedal bicycle with whicker basket for the wife. Addding an engine to make it go faster underlines the limitations. Adding suspension increases the asymmetric compromises.
This is why dedicated sidecars with a specially designed, fabricated chassis on car wheels/tyres are a thriving business in Europe.


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¡YESSSSS!
Fínally.
David Angel of SimplySidecars.co.uk took the time to explain the root cause of the low speed wobble.
It is the toe in x tyre adhesion x sideways tension on the front fork.
The toe in sees the front tyre pull the front towards the sidecar. This loads the front fork. When the load becomes high enough, the fork forces the tyre to release the sension. Because of the mass of the front fork it will overshoot. Repeat. This induces a judder which because of the steering head angle is in effect a wobble.
As speed increases the frequency increases and the tyre creep too, meaning the wobble disappears.
Tatáááá,
Thanks David; I would nevvah evvah would have thought of that.

It also explains why both increasing tyre pressure as well as lowering works. The first because it reduced traction thus allowing the tyre to dissipate the tension, The latter because the greater deformation allows for more creep, also dissipating the tension.
Both have their down side. The first means also less traction for cornering/braking and the second introduces serious understeering.
Cool :cool:

Lóve the 'sound' of pennies dropping. This insight makes me smíle.
 
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The trick with tyre pressures is to find the set up that gives the best balance between
head shake & handling, that's where the experimentation comes in. Not forgetting
that a change in load can alter the handling as well.
 
Rider0974 said:
The trick with tyre pressures is to find the set up that gives the best balance between
head shake & handling, that's where the experimentation comes in. Not forgetting
that a change in load can alter the handling as well.
Click to expand...

Quite. Any change in load means different adhesion of the front wheel ergo changed break off moment.
This also explains why a different rider/driver or per example simply leaning a bit forward changes/shifts the wobble.

Also a change in front try compound shifts the balance.

With tyre pressure I am véry hesitant as the change affects the traction and thus indirectly steering:
Up = less grip for braking
Down = understeer
As such I only adjust for the load if/as specified by the manufacturer.

Now I understand the root cause I also totally get what the effect of more/less lead, more/less lean out and more/less track width are.
The simplest to illustrate is wider track. Because of the longer 'lever' the toe can usually be less, which means less sideways pull by the front tyre.
As always with this asymmetrical anachronism, áll is interacting.
 
an alternative, very left field approach to the sidecar wobble...

www.bbc.com

Oadby: Therapy tortoise helps schoolchildren with stress

Billy's owner, who works at the school, says students love seeing him as he has "a calming presence".
www.bbc.com www.bbc.com

She said Billy helped when students "are feeling a bit overwhelmed or a bit wobbly".
 
Totally a-typical weather again/still. After an 'autumn' weekend one sunny day and then another week of iffy with rain.
Asked the ex+1 and she said ofcourse so rolled out the rig, up the road and the next step dog training. Him on her lap in the sidecar and a very short spin up third gear.
I would call it a draw between positive and negative. No panic but he did not relax.
Weird thing was that when I put on my gear to leave he jumped and vocalised as if wanting to go with me.
Better let it sink down with a 'want' and repeat with ex+1 next time.

On the return trip took the highway. The rig is surprisingly pleasant at 'high'er speeds. It is só comfie at 100-110 km/h and stayed totally neutral at 130 which was as fast as I went.

Next is fit the fire extinguisher.
 
Petrus said:
Totally a-typical weather again/still. After an 'autumn' weekend one sunny day and then another week of iffy with rain.
Asked the ex+1 and she said ofcourse so rolled out the rig, up the road and the next step dog training. Him on her lap in the sidecar and a very short spin up third gear.
I would call it a draw between positive and negative. No panic but he did not relax.
Weird thing was that when I put on my gear to leave he jumped and vocalised as if wanting to go with me.
Better let it sink down with a 'want' and repeat with ex+1 next time.

On the return trip took the highway. The rig is surprisingly pleasant at 'high'er speeds. It is só comfie at 100-110 km/h and stayed totally neutral at 130 which was as fast as I went.

Next is fit the fire extinguisher.
Click to expand...
Sometimes it is about wanting to be with us, but not necessarily the experience of achieving that.
My fur child always wants to be with us, but doesn’t really enjoy being in the car. He is 16 and has always been that way.
IMG_0997.jpeg
 
HUNTS said:
Sometimes it is about wanting to be with us, but not necessarily the experience of achieving that.
My fur child always wants to be with us, but doesn’t really enjoy being in the car. He is 16 and has always been that way.
Click to expand...
Thanks for sharing. Quite an impressive age btw.
He lóves traveling in the car. It is why I am making such an effort because if he does not enjoy it, I am not taking him along :cry:
 
about safety; my apologies 🫣

I first want to share a photo

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This is a snapshot of Nimbus club ride out.
It is pottering about and max speed on route being say 70 km/h.
Safe full face helmets, hi-viz etcetera.
One without gloves and both passengers on the pillion :rolleyes: . Ah the high-viz hidden behind the driver.
Because of VERY old design and thus limited electrics, very few of these Nimbus rigs have a headlight worth that name.

A traditional motorcycle with sidecar rig is as a vehicle a .... how do I put that politely?... 'limited' concept. That observed it also has húge bonus consequences for safety.
Even though the asymmetrical lay out is tricky I overall rate the third wheel as a very safe extra.
Next it is very different and that makes it noticed thus registered, séén by other road users. Also because it is different they tend to keep their distance even give it right of way when it does not have it.
The latter also stemming from curiosity, wanting to see it better.
And thát in its turn originates form a very positive, romantic even, image of this anachronism on three wheels.

Back to the Nimbus rigs. Most drive about with weird safety choices whereas in the current era the presence itself makes it 'safe´. With the Nimbus rig they get more space than an ambulance!!
All in all I am breaking a lance for the concept in the light of safety.
 
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