The R18 sidecar thread

[Petrus]

On a sidecar rig the side stand is superfluous and can be deleted.
The delete switch I sourced did not work.
Nor is it needed. You can simply take the side stand off and house the position switch in the bracket on the frame. Electrical tape around the switch, push it in the bracket and a tie wrap around it will secure.

 

[HUNTS]

Arrrrgggggg.....
Yesterday collected the parts from the workshop.
The front tube is júst off. Just is the same as completely though as cannot fit.
The workshop in the village can correct this but has no time today. Máybe Monday.

Rather p...ed off as it could have been easily sorted wééks ago. My own fault for being patient and courteous.

Fitted the rest. Drove the rig in reverse out of the garage but could not go further because the exit is blocked by a car from a neighbour. Thus in first back again. So, in a way saved from going out on the road

View attachment 20528

Some days just ain’t your day… the numerous hints kind of tell you that.

 

[Petrus]

The neighbour went off.
I parked mine in place with enough room to pass.

Was a bit of a faff and the conclusion is that I need to turn inside and drive out forward. The ramp is too hard work for the reverse electrics.
The upside is that it easier to watch where I am going.

Since there is a critical strut missing drove only 100 meters either way with corresponding turns.
Tomorrow re-align and retighten.

While I passed the drive, two elderly ladies walked by and up to my wife waiting in the entrance. Mán they were enthusiastic. Wanted to seen the Nimbus rig too and ´ahhhhh Véspas!!´
The sidecars though totally steal the show.
As I observed earlier, I don´t know what it is but sidecars are total woman magnets. They see it as romantic.

Anyway, have the jack under the frame, the gold ingot on the cilinder, took the locking pins out. The straight edges ready too. Tomorrow tie-wrap the latter and loosen all connections.
Align and retighten.

I am not sure I like the Rock mode with the chair fitted. Will try Roll next time. Same power just smoother. Befits the rig better I suspect.

 

[Petrus]

Raining so perfect day to do some spannering.
Loosened all though not all at once to keep the lot from collapsing.
Set is up again, toe in with help of charming assistent and after .... got it right and retightened.
So; time for Ruta de la Tapa.
Tomorrow, after cycling, double check if I forgot nothing, befóre going on the second part of the Ruta.

 

[Petrus]

Everything retightened and at least double checked. If only that last strut
The short test mentioned earlier did point out that the steering damper works btw.

Meanwhile keeping my spirits up with my Vespas
Showing some newbies around and got the PK125 of a local artist going again. Tomorrow helping with cleaning ´tagarninas´ for the upcoming fiesta weekend.
That last strut is basically ´making´ me behave social

Meanwhile for the strut.
It is supersimple to correct but the booming economy means all are inundated with work so there is little/no interest in a 30 minutes faff.

 

[Petrus]

The local ´welder´ dropped by at my place to have a look and he thinks it´s most efficient to roll up with his mobile workshop and modify the connection here.
Maybe late this evening, maybe tomorrow.
At least he is a classic motorcycle enthusiast

 

[Petrus]

The strut is done. Pits perfectly.
Cleaned, sanded, painted. Tomorrow repeat.

Work in progress:

 

[Red64]

The strut is done. Pits perfectly.
Cleaned, sanded, painted. Tomorrow repeat.

Work in progress:

View attachment 20561View attachment 20563

Amazing!

 

[Petrus]

An intermediate observation confirming the earlier comment on it; ´Rock´ mode is not really compatible. The rocking is transverse and that equals shaking all fittings and worse still the tub on its rubbers.
In ´Roll´ all is stable.
Slow speed ditto. The ´Rock´ mode makes the engine notably more rough on the transmission in an unpleasant way. ´Roll´ is smoother.

I am very véry glad I decided to use a sturdier rear bottom mount and a fifth mounting: The R18 is a rather a serious tractor.

The latter leads me to another observation: Some vintage ´torpedo´ model sidecars had a loop running from the wheel side chassis tube to the bike side tube. Anchoring the fifth mounting to thát would be a order more stable.

 

[Petrus]

All fitted and adjusted:

125 cm. track width
34 cm. lead
18 mm toe in
4 - 5 mm lean out (rider in saddle, 40 kg ballast in tub)

 

[HUNTS]

All fitted and adjusted:

125 cm. track width
34 cm. lead
18 mm toe in
4 View attachment 20568View attachment 20569View attachment 20570View attachment 20571- 5 mm lean out (rider in saddle, 40 kg ballast in tub)

Where’s the ‘Eject Button’ for when your passenger gives you the ?

 

[Petrus]

Where’s the ‘Eject Button’ for when your passenger gives you the ?

Just fly the chair and that´s sorted; either shuts up or wants out voluntarily.

 

[Petrus]

First véry tentative real test:

Only up to 50 km/h.

So easy. Só stable. If anything the bike rides easier than solo.
Mild accelerating and medium braking the sidecar is hardly noticeable.

Sofar happy camper.

One LED bulb was too loose in the fitting: Easily solved.
The mud flap is too rigid. Will delete for the moment.


View attachment WhatsApp Video 2026-03-19 R18-2.mp4

 

[Petrus]

How it all started btw; with a competition in 1893 in a French newspaper about the best way to carry a passenger with the bicycle. It makes the sidecar predating the motorcycle

 

[Petrus]

Today a drive through and around the village.

Drove a treat. Só smooth and stable. The chair is hardly noticeable but HÚGELY contributing to riding comfort: This village is all inclines at all imaginable angles and narow streets thus fantasy angled tíght turns. Rather a difference with navigating the >350 kg bike solo.

The reverse gear, imo a must on a rig anyway, is só

Was a bit disconcerted by a ´shaking´ noise when passing over rough surfaces. Back in the garage think I identified it as the seat juttering in the lock. Will try some gaffer tape.

MUST mention the attention the rig draws. Just about all pedestrians stopped to look and when I stopped for the photo several walked up.

 

[Petrus]

Glorious day today. So, being retired, rolled out the sidecar. To the gas station to fill up a reserve canister. Also dropped a set of tools, spanner sizes of the mountings, in the boot.
Despite of, or rather because of, ample experience took it veryvéry easy.
Surprisingly neutral steering. Hardly pulling right or left. Accelerating and braking as without.
Because the R18 is só heavy, one does need some caution through corners. Because the rig has so much oomph it is all to easy to motor into corners too fast.

Next loaded up with passenger after taking out the lead ballast ingots. Same really just a bit more stable.
With the live ballast gave it some more throttle and have nudged 120 km/h on the undulated country road here and stayed neutral, stable.
The downside of this is that accelerating or decelerating are not in the toolbox to manage bends/corners.

The sometime charming passenger was not today. She is still diametrically opposed to the sidecar and now added being scared to it. Tant pis.
If she can not be charming company than she best not be company at all. Life is too short for that.
Adding insult to her perceived injury is that EVERYWHERE people wave, shout, honk etcetera, especially women.
I think my biggest issue will be taking out/putting back ballast

 

[Petrus]

Out for a trial an nó!! error run again. This time up a real rough road up to the hermita en source of El Chorro.
First dropped in at the local garage who signed off the fitting.
And finished with a coffee at a Venta down the road.

 

[Petrus]

Yesterday evening drove to an exhibition and performance art by a friend. Twas up in Iznajar Castle (do look it up) high above the Iznajar lake.
The ride from Salinas to Iznajar is It is a continuous string of curves and bends with perfect tarmac and great views. As such nothing out of the ordinary here
So why mention?
Well I had an embarrassing epiphany.

In a way I knéw, know, I just did not have it this crystal clear.
I have driven lightweight MZ sidecars, a 2WD lardy Dnepr and a rigid Nimbus. Vastly different but for various reasons sort of compromised and thus one instinctively expects the performance restrictions, especially cornering.
Now have the R18 and... cornering restrictions are THE SAME!

It stands to reason of course and as observed I knéw really but it was not in the forefront of my daily technical awareness

Bolting a generic sidecar to a traditional road going motorcycle is compromised by design. All laws of physics apply the same way and result in pretty much the same cornering performance.
Depending on engine power and the brakes, the rig accelerates faster and stops shorter but cornering is set by weight, c.o.g, weight distribution and centrifugal forces.

The above mentioned road is hard confrontation with this.
I was stúnned by my hard tailed 89 year old Nimbus cornering better than the R18 rig, better than the MZ and Ural/Dnepr. Mind the 1939 motorcycle is not a practical proposition and the R18 is absolutely awesome but mán, the realisation of the conceptual boundaries is

 

[Red64]

Yesterday evening drove to an exhibition and performance art by a friend. Twas up in Iznajar Castle (do look it up) high above the Iznajar lake.
The ride from Salinas to Iznajar is It is a continuous string of curves and bends with perfect tarmac and great views. As such nothing out of the ordinary here
So why mention?
Well I had an embarrassing epiphany.

In a way I knéw, know, I just did not have it this crystal clear.
I have driven lightweight MZ sidecars, a 2WD lardy Dnepr and a rigid Nimbus. Vastly different but for various reasons sort of compromised and thus one instinctively expects the performance restrictions, especially cornering.
Now have the R18 and... cornering restrictions are THE SAME!

It stands to reason of course and as observed I knéw really but it was not in the forefront of my daily technical awareness

Bolting a generic sidecar to a traditional road going motorcycle is compromised by design. All laws of physics apply the same way and result in pretty much the same cornering performance.
Depending on engine power and the brakes, the rig accelerates faster and stops shorter but cornering is set by weight, c.o.g, weight distribution and centrifugal forces.

The above mentioned road is hard confrontation with this.
I was stúnned by my hard tailed 89 year old Nimbus cornering better than the R18 rig, better than the MZ and Ural/Dnepr. Mind the 1939 motorcycle is not a practical proposition and the R18 is absolutely awesome but mán, the realisation of the conceptual boundaries is

I can only imagine how challenging it is. But I guess same as when i had the rig on the Z1300 judicious use of front brake and down a gear and hard acceleration helped with cornering. With the torque of the R18 I can only imagine the improvement. Down side: High fuel consumption! And front brake
wear.

Of course brake and throttle usage opposite to what I was used to in Australia with the rig on the opposite side. So hand full of front brake swing into the left handler and down a gear and accelerate into the Right handers

 

[Petrus]

judicious use of front brake and down a gear and hard acceleration helped with cornering.

unfortunately the weight/air resistance/rolling resistance of the R18 vs that of the Velorex makes that accelerating and braking have very little ´cornering´ effect.
It is best illustrated by up shifting during hard acceleration; next to no effect on stability.

Next is a lead ingot more in the chair. Currently 3 x 12.5 kg. + 5l. reserve gasoline and some tools.