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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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Right back to the more humdrum order of the day.
Over some rough surfaces the tub makes a racket most akin to panel drumming.
I have checked/tightened all that can be checked/tightened but nothing looking like the possible culprit.
Cut a piece of left over carpet to size for the rear floor and bolted the ballast weights down on top.
Again not the most likely, more like neat upgrade because at it anyway.
Asked around and because the rear luggage compartment is a large empty grp box it ís prone to panel drumming under certain circumstances. Well apparently my use meets those.
Ergo self adhesive sound deadening matt should do the trick. The ubiquitous alu backed fibre is too light in my experience and bitumen matt probably overkill so rubber it is.
 
Went for another trial run. No rattles.
Now I did make a fundamental mistake ☺️ I changed THRÉÉ things:
Tightened all bottom bolts; tub and seat,
put a piece of tapistry under the ballasts ingots
ánd put a box with magazines on the seat as extra ballast.
Thus have not ascertained whether the ingots were the culprit or the seat was.
Reason for the box is that I am very cautious getting to know the rig as the tractor is heavy beast. Anyway, as is no disconcerting/distracting sounds.

Ah and tanked. A bit weird because the bike is upright.
Also very easy maneuvering on the pump yard and no double take on slippery surface putting the supporting foot down.
 
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As you have also seen in the photos I am meanwhile pottering about getting to know the rig.
It is my fifth but there is definitely a different, additional learning curve.
I remain that the pedal bicycle concept of bolting a ´stand alone´ sidecar to a ditto standard motorcycle is inherently compromised. Suspension (wheel travel) of the tractor and chair vs the rigid bicycle ancestor upset the concept another dimension.

The heavier/more powerful the motorcyle and/or lighter the chair, the more compromised. Generically a weight balance between the two of the chair weighing 30% of the tractor.
This is very rough though because the height of the c.o.g. and the wheelbase of the tractor affect the dynamics. The lower the cog and longer the wheelbase the lighter the chair can be.
Same thing the track width. The wider, the longer the arm over which the downward moment works. The resulting effects of the centrifugal force on the tractor vs the gravity on the chair are evident.

The ´obvious´ conclusion to draw is that a heavier char is safer. Well... yes, but; as usual with the sidecar concept, there is a big but: The heavier the sidecar, the more forces the front tyre needs to relay to the road surface. This puts equal strain on the fork and wheel.
The lighter the chair, the easier the fork/wheel/tyre can steer the rig and vv.

Ok, to the R18:
The base model is say 350 kg, making 30% some 117 kg.
A tc model makes the chair weight some 150 kg.
Calculate the total weight depending on the loads.
Back to the front tyre. Remember that all asymmetrical forces are compensated for by sideways forces through the front tyre.
It now becomes easy to understand why the heavier the chair, the larger the benefit of a swing arm fork and flat profile tyre.

Ok the learning experience sofar:

1. The R18 is so heavy, still, strong that the sidecar makes less impact on the riding than expected. In my case the chair is aerodynamically quite ´slippery´ i.e. less pushed back by the riding wind. All in all less effect on braking/accelerating.

2. The heavy tractor pronounces the effect of the motorcycle on the cornering. Best illustrated by right handers where the centrifugal forcers on the heavy tractor easily make the lifting torque on the sidecar outweigh the downwards torque of gravity.
You understand that this is same in left handers, just with sideways forces on the front wheel.
A lighter chair has a lower limit to the right and a heavier chair to the left.

3. The engine is silly powerful. Mine has the air entry improved so say 100 hp but more importantly more torque more instantly. In an instant the rig does 120 km/h. Corners/bends come up FAST. See point 2. :eek: The brakes though are easily up to the job.

4. The gearing is already on the long side for the solo bike and more so for the rig. The heavier the rig the more exaggerated this will be.

Right, looking at car type tyres for the R18 but no....
 
Texas Sidecar Comp. has just written an article on sidecars on Facebook. It is obviously from the p.o.v. of a hair dresser whom you have asked if you need a haircut. Their claimed 50 years of experience surely tought them that sidecars are an inherently compromised concept which no set up can change.
He also plucks the sidecars on the IoM out of the air for comparison which is total bs. Period.
As such I just hád to respond.
It is almost funny that their ´camber adjustment´ underlines the asymmetrical nature of a sidecar and that set up is a compromise. Stating anything else is misleading customers.

It must be understood that the classic bike with bolted on sidecar can in NO way be compared with integral three wheeled ´sidecar´ designs. Never mind racing rigs which have multi link steering/suspension and even the engine mid mounted for optimal weight distribution.

Classic sidecars are immense fun IF the user understands, expects the properties and compromises of the concept. When not it is a mishap/accident waiting to happen.

Rant over.
 
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Did another CRC alchemy trick: Now have 4 12,5 kg ingots with a handle.
2 bolted down behind the seat, 2 velcro-ed on the carpet right in front of the seat.
As such now have 50 kg QD ballast.
The idea is to minimise the difference between loads. Leave in take out ingots as needed.
 
This morning walked up to the local shop who has a print service to collect a Spanish red tape essential.
Got stopped by a police officer.
´Are you home today?´
Later yes, how come?
´We would want to come by. Please note this local station phone number and call us when you are in.´
Two hours and this particular red tape solved later I drop them a call.
´Ok we will be there in 10 minutes.´
:eek:

8 minutes later PingPong...

If they could see my sidecars as they lóve motorbikes 🤪

After some :cool: they observed that they also had come to mark the official no parking exit I had asked for at town hall.
I said I needed 2.0 meters wide and ´Nooooo..., you want 2.5!´
After some deliberation they generously marked the corners for the council workers to paint my exit.
(y)(y)(y)
 
As sideways mentioned my wife did, wonderfully inconsequently, NOT agree with me buying a sidecar. ´Am nevvahevvah going in it!´
Thus I went on the test drives with lead ingots in the tub: ´Why do you nevvah take me along; do you want me not to come?!´
So I offered to take her for a ride to a Venta up the road for lunch: ´Now I not hungry´.
Thus I drove her back. ´It is horrible; I am scáred stiff in it.´
So next day went out with the lead again. You can guess...
I refused as the lead at least does not spoil any ride!

Since the rest of the relationship suffered much of the same I have pulled the plug.
If I were 35 I would have tried make it work but at the threshold of 70 .... not.
The next challenge is to find a female passenger more charming than the lead ingots. You would think that bar not very high but realistically it is. The pond I can fish in has plénty of fish but very few lively 😒 Very sad but there you have it. Better train my dog to like it (y)
 
Today first session of good company sidecar passenger training.

Asked my ex+1 to tell my dog I was coming and put him of the front terrace.
He totally understands it is me and this way the R18 was good news.
She let him out jumping and running, playing about around the rig to greet me.
Started the engine. Repeat play and fun.
Engine off, coffee inside.

Phase two.
Gave him a treat. ´Sit´ofcourse.
With the second treat seen by him in my hand outside.
Put him in the tub, ´sit!` treat. when calmed down a bit ate two treat while on the seat.

Ok, quit while you are ahead.

Next time same routine and depending on how relaxed he is with engine running. If too excited then no step up, just consolidate.
To lower the bar, will next time put his sleeping basket in the seat.

Following step when confident with engine running is ex+1 in the seat, him on her lap.

When thát confident, a short ride. with him on her lap.

Etcetera till eventually him with his basket on the seat.

Seems a bit too cautious but this is a very highly strung ´piccolo´ and it is like with racing horses. ´Saw tooth´method. Two steps forward, one back. The néxt second step forward only when confident with the previous. If you go to fast, it is waywáy more effort to get it built up again.
My male Frenchie would been in at a flash. The challenge being to keep/get him oút 🫣
 
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Petrus said:
Today first session of good company sidecar passenger training.

Asked my ex+1 to tell my dog I was coming and put him of the front terrace.
He totally understands it is me and this way the R18 was good news.
She let him out jumping and running, playing about around the rig to greet me.
Started the engine. Repeat play and fun.
Engine off, coffee inside.

Phase two.
Gave him a treat. ´Sit´ofcourse.
With the second treat seen by him in my hand outside.
Put him in the tub, ´sit!` treat. when calmed down a bit ate two treat while on the seat.

Ok, quit while you are ahead.

Next time same routine and depending on how relaxed he is with engine running. If too excited then no step up, just consolidate.
To lower the bar, will next time put his sleeping basket in the seat.

Following step when confident with engine running is ex+1 in the seat, him on her lap.

When thát confident, a short ride. with him on her lap.

Etcetera till eventually him with his basket on the seat.

Seems a bit too cautious but this is a very highly strung ´piccolo´ and it is like with racing horses. ´Saw tooth´method. Two steps forward, one back. The néxt second step forward only when confident with the previous. If you go to fast, it is waywáy more effort to get it built up again.
My male Frenchie would been in at a flash. The challenge being to keep/get him oút 🫣
Click to expand...
It would be nice to see some pictures of the process
 
HUNTS said:
Your fur child either dislikes sidecars or R18s… looks terrified.
Click to expand...
He is like a highly strung pure bred racer. Well not líke; he is 🤪
It shows the sense in the sawtooth training method.
We´ve progressed to eating treats in the chair.

Next sessions a bit delayed because of mé being :oops: as result of the separation/divorce proceedings. Not a confidence inspiring state 😒
That observed, life is too much FÚN!! to :cry: over.
 
Un píccolo!! Italian ´greyhound´.
His coat is called brindle but over here such guised sighthounds, ´galgos´, have a different name just for them; ´barcino´.
He is a bit on the corpulent side because he has the run of the farm; literally.
Sighthounds are very much appreciated here. So much so that per example in Málaga there is a specialised pet shop.

1776753823721.png
 
Petrus said:
Un píccolo!! Italian ´greyhound´.
His coat is called brindle but over here such guised sighthounds, ´galgos´, have a different name just for them; ´barcino´.
He is a bit on the corpulent side because he has the run of the farm; literally.
Sighthounds are very much appreciated here. So much so that per example in Málaga there is a specialised pet shop.

View attachment 20893
Click to expand...
“Mmm… if I can swim to that house, I never have to get into that sidecar thingy again” 🐾
 
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