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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=1789222567#check"></use></svg></i> Discussion starter Discussion starter Petrus
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btw @R2K
If you can, pls ascertain the set up specifics: track width, sidecar wheel lead, toe in, lean out. It would be a perspective for your driving experiences (y)

Because it is basically ALL variables with sidecar builds there will always be more to learn and I lóve that.
I mean after half a century of sidecar experience only thís year I had the penny drop about the whý of the ubiquitous low speed wobble. Yes, I knew how to deal with, possibly do about it but the reason escaped me. The ´aha-erlebnis´ was 😎
That progressing insight is why I am looking éxtra forward to the flat profile front tyre.
 
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Thanks for sharing @R2K

Heavy being close to 600 kgs. and with the torque of the R18 still quite a lively thing.

I meanwhile have been out with the Nimbus rig and also, with the Vespa went have a look at a NotSoModern (2 stroke shifty) Vespa rig. Want it!!

Vespa150Inder.webpVespa150CL1.jpg
 
Quite, isn’t it under powered?
 
R2K said:
Quite, isn’t it under powered?
Click to expand...

Depends.
This 150 has 9 hp and solo gets up to 90 km/h.
Remember it is a Vespa ´large frame´ with 10" wheels., two stroke, hand shift. with tricky clutch and euhhhmmm :eek:interesting drum brakes. The design goes back to 1957 with just some marginal updates. They are let´s say an off main roads only adventure in solo guise.

With sidecar definitely more no-fast, but the handling is equally more .... challenging so one can happily do without more engine output 🫣
Bottom line it is under powered in modern traffic but borderline over powered for the handling.
I would possibly swap the stock exhaust for a Polini big box which gives a bit more at low/mid revs. but most definitely not a cylinder kit.

Over here Motovespas (made in Madrid) were just like in Italy the wheels of the working class. The Seat 600 added the psooibility for more kids and larger distances but for local use the Motovespa ruled for decades.
The plant was founded in 1952 as a joint venture of the Spanish ministry of industry and Enrico Piaggio. With up to 1.000 personel they produced the two strokes for 51 years.
Driving such a cultural icon over here in the interior of Andalucía is alien to the US.
Even England with it´s London - Brighton veteran run is way less tolerant to classic vehicles in traffic than Andalucía.
In per example Antequera the two-stroke shifties are a common sound in daily traffic, especially during rush hour. In Málaga they may be less abundant but are still a common sound.
A perspective are 50 cc equivalent electric hire scooter projects. In Granada, Málaga, Cordoba, Sevilla there are electric Vespa replicas one can hire using an app. Pick one up near you and leave it parked where you want to be. Those go max 40 km/h.
 
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optical illusion :oops:

HeidenauSidecar.jpg

120/70 x 19 vs 4.00 x 19 sidecar.

The 120 measures júst under 120 mm. wide. No, not over the curve, actual width.
The 4.00 is ... 100 mm.
 
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This morning fitted a connection in the wiring between bike and sidecar. Should have done that when connecting but at the time was completely stressed out about the CANbus.

The Vespa rig is now on my name. Next is getting it through periodic inspection. Then drive it up. Four short words for a nigh epic drive up from the coast óver the mountains to the inland side.
 
Petrus said:
btw @R2K
If you can, pls ascertain the set up specifics: track width, sidecar wheel lead, toe in, lean out. It would be a perspective for your driving experiences (y)

Because it is basically ALL variables with sidecar builds there will always be more to learn and I lóve that.
I mean after half a century of sidecar experience only thís year I had the penny drop about the whý of the ubiquitous low speed wobble. Yes, I knew how to deal with, possibly do about it but the reason escaped me. The ´aha-erlebnis´ was 😎
That progressing insight is why I am looking éxtra forward to the flat profile front tyre.
Click to expand...
As requested,


60 in track width


Lean out 3 degrees


Toe in 1/8th in


Sidecar wheel lead roughly 10 inches

The rig is complete and should be delivered tomorrow pictures are forth coming…..
 
thanks;

so in metrics

track width 152,4 cm (mine is 124)
lean out 3 % (mine is 1%)
toe in 3.17 mm. (16 mm)
Lead 250 mm. (300)

Vastly different from mine but makes sense in the light of the track width and the lean out.
The toe in is off the scale small. For the lead it is usual more like 25 mm.
The lead is not a lot for the wheelbase.

It is such a good example of sidecars being all variables.
Also highlighting US vs European as we over here go as narrow as possible because of nimbleness.

The rig will be a lót more literally straight forward, stable and forgiving.
The lack of toe in should about eliminate low speed steering wobble. If the rig pulls to the chair, then increase toe in.
You will also have more ´sidecar effect´ i.e. pulling left/right upon acceleration/deceleration.

Só looking forward to progress reports!
Very happy for you that is is COMING!!!
Ah, tip; start getting used to it in ´RAIN´ mode.
 
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Got round to fitting the Heidenau K28 sidecar tyre up the front.
It doúbles :eek: the contact area with the road.
Only doen a short stint but is was varied use:
I have not noticed the previous ever so slight tendency toward a wobble.
Also is sééms to be lass effort cornering left.
The basic difference is more stable tracking.

R18Voorband.jpg
R18ZijspanVoorband.jpg
 
Congratulations!

That is on serious looking rig (y)

The sidecar ride hight / lean adjuster looks :cool:

Enjoy!

On a side note very pleased to see the fitter opted for the same PITA solution for the top front as I did.

p.s. I would have a look at the extension on the sidecar axle. It rather sticks out. Be careful with that as that side of the sidecar is out of view. On my relatively narrow Nimbus rig have a crash bar sticking out 5 cm and I stíll managed to scratch the mudguard :oops:
 
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Done several 100 kms now with the flat tread tire and difference is wonderful. The tire is múch more stable, asks less steering effort especially in left turns.
In turns to the right the fact that the front does not roll over the profile results in a much more predictable feeling about chair ´lightness´. Furthermore the tire makes the rig less susceptible to road camber again same reason as above.
Lastly the flat profile is not in the léast sensitive to ´black snakes´.
Ah and no more tire noise.

Today went for a 6 hour non stop twisties route. Inluding extreme twisties up down, around the SW side of lake Iznajar. Would have been a challenge with the stock tire, was a great fun workout now. A challenging route and nóthing comes close to the sidecar experience. Not even an NSM Vespa. You are out in the open air like any motorbike, enjoying max view, smell, you name it. Also múch more involved in the route because you need to WÓRK it but without the clenched @rse when the rear or front wheel moves sideways on some gravel.
 
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