The R18 sidecar thread

[R2K]

“Mmm… if I can swim to that house, I never have to get into that sidecar thingy again”

lol

 

[Petrus]

“Mmm… if I can swim to that house, I never have to get into that sidecar thingy again”

there are >2 m. long catfish in that lake and he is quite clever enough to not go as far in as wetting his chest even.

 

[HUNTS]

there are >2 m. long catfish in that lake and he is quite clever enough to not go as far in as wetting his chest even.

Looks like a Rescue Helicopter needs to be called then

 

[Petrus]

Looks like a Rescue Helicopter needs to be called then

Nah, grown up running over the rough he does near top speed anywhere and goes around the shore close to 1 km in a minute. He also sees a lot better so does not perceive distance as we do. It is amazing.

These are two other pets so have my own Aesop´s fable

 

[Petrus]

After some riding around wanted to check all fittings, change the angles of upper front and fifth mounting a bit and with all loose give it a mm more lean out.

The upper front is now more vertical and all more directly angled, meaning less rotating forces on the fittings.

The anchoring of the mid/fifth on the sidecar chassis I have shifted more forward so it is now more angled forward. This is the reverse angle direction as the top front and to rear thus triangulating better.

All fittings were pretty tight btw.

 

[Petrus]

I am an avid reader/student/researcher. Even though I have several decades of experience with four sidecars, you do not know what you do not know; there is always more, állways. Applied to sidecars this is accentuated by the unique asymmetric nature of the anachronistic contraptions.
As such I never get tired of reading about these misfits, oops sorry outfits.

Currently reading experience based practice generously shared by a professional old skool outfitter. 'Old skool' not because he has not kept up with modern times like CANbus or reprogamming ECUs but because since the seventies he has worked on traditional rigs. Urals, Jawa, Velorex are his main interest but he will expertly make a reliable, good handling rig of nearly ány modern motorcycle.
Anyway his proza is delightfully practical to the pint of being amusing.

An example:
'If you have only ever ridden solo bikes turning the bars will feel odd, they need to turn further than you think. All direction changes should be done by pushing with your palms, always add weight to the bars, never pull with your fingers. Pulling the bars gives much less control, and takes weight off the bars. Pulling is much more likely to cause handlebar shake. If the front wheel is not pointing in the direction you want the combination to go it will not go there.'

Or:
'If you only pick up one tip from my writings it is this: You should feel the pressure of the bars in the palms of your hands and never in your fingers.'

I lóve it.

 

[Petrus]

There is thing with sidecar rigs which bugs me.
All traditional rigs, the rare exception confirming this rule, shake their head within an akin low speed window.
A steering damper will mask it but the tendency will still be there.
My MZ with three point fitted Elastik and Dnepr MT16 2wd both did.
My Nimbus with hard tail and rudimentary undamped front fork does as does my R18 Velorex rig.
Even rigs with a leading link fork will.

As such it must be a thing dictated by laws of physics specific for the asymmetrical concept.
Since I like to understánd things it bugs me.
Can´t squat thís bug so I ignore it but every now and then it pops up again.
AI being a new thing tried thát but no way.

Back to my Nimbus I noticed that the change from a motorcycle tyre with round profile to a sidecar tyre with flat tread shifted the wobble. Not necessarily improved; slightly less pronounced but at a slightly higher speed. The friction steering damper easily sorts it out but it is there.

 

[Rider0974]

All my sidecars have had a bit of a head shake, I found experimenting with tyre pressures,
by raising or lowering them a few PSI, made a difference. It is a case of try it & see what works,
& what doesn't. I never completely cured the wobble, but did get it so I could ride one handed
without any issues

 

[Petrus]

All my sidecars have had a bit of a head shake, I found experimenting with tyre pressures,
by raising or lowering them a few PSI, made a difference. It is a case of try it & see what works,
& what doesn't. I never completely cured the wobble, but did get it so I could ride one handed
without any issues

Thanks for sharing.
You illustrate my 'issue'; they all do but... whý??
For one it then would not be trial and hopefully not too much of an error but more importantly for mé; understanding.
I mean front tyre drift/creep seems to be a factor but sometimes the happiest medium is more and sometimes less is.
Then there is the rider. A different body position or simply holding on to the handlebars differently affects the shake.
The whý bugs me.

 

[Petrus]

The training continues:

 

[HUNTS]

The training continues:

View attachment 20999
View attachment 21000

As a Dog Groomer of the past 12 years, I absolutely love your fur child. I would love for you to get a nice photo in your sidecar with a great background and if suitable, I would love to post it on my Facebook page (see Jaffles Mobile Dog Grooming) with your permission, of course.
Once I have a suitable pic, I’ll get some more info for my followers to read about.
See, isn’t the world of R18 a wonderful connecting place .
R18t is Might.

 

[Petrus]

As a Dog Groomer of the past 12 years, I absolutely love your fur child. I would love for you to get a nice photo in your sidecar with a great background and if suitable, I would love to post it on my Facebook page (see Jaffles Mobile Dog Grooming) with your permission, of course.

will be happy to as soon as he is fully at ease in the seat and it would be an honour

 

[Petrus]

btw @Rider0974 do you remember / have you logged what your rig's geometry settings were?

The R18 being a HÉAVYweight bike with long wheelbase and quite a bit of trail with a featherweight sidecar was a bit of a challenge as the ubiquitous ball park dimensions did not pan out.

I now have the sidecar axle lead at 340 mm which is 19.6%.
Track width is 1250 mm.
Toe in is 16 mm.
Lean out only 2 mm.
Rear suspension preset on 170 kgs.
I have the mode in Roll as Rock is imo too brutal.

I find that the heavyweight vs featherweight makes for a delightful combination although it should be noted that with extra petrol, tools and ballast, have 60 kg load in the sidecar. Take the 50 kg ballast out when loading up charming company.
The weights make that the sidecar has very little effect on directional stability.
Reduced lean is because the centrifugal forces on the heavyweight otherwise make me feel uncomfortable in right handers.

The preset I had maxed out but that was too much for mé. Now it is about on par for the load.
Note to other builders: The R18 has a limited max. load and about half the weight of the sidecar should be counted as load. This means no more pillion ride (bad idea anyway with sidecar) and also the rear shock may need be replaced for a beefier one.

Depending on the use, where one lives I would suggest NOT fitting 'camber adjustment'. This is nothing more or less than ride height adjustment of the sidecar suspension. That affects the lean out of the tractor. It thus changes the stability of the rig. Unless one travels a straight road with smooth tarmac to beyond the horizon, the negative outweighs the positive.
Additionall a for mé unacceptable negative is that if one needs to swerve/cross over the crown of the road, the rig immediately changes to wanting hard left. Not something you want to add to avoiding manouvres.

 

[Rider0974]

Hi Petrus, I have never had to worry about the settings of any of my sidecars, as I
have bought them used, ready to ride. The exception is my current outfit which I
had fitted by Watsonian Sidecars. I have never bothered with ballast in any of my
sidecars, & have ridden them solo, with my wife as pillion & empty sidecar, & with
my wife as pillion & my Mother & 2 children in a Watsonian Oxford 3 to 4 seat sidecar.
My current outfit is a Kawasaki VN1600 & Watsonian Monaco single seat sidecar.

 

[Petrus]

Hi Petrus, I have never had to worry about the settings of any of my sidecars, as I
have bought them used, ready to ride. The exception is my current outfit which I
had fitted by Watsonian Sidecars. I have never bothered with ballast in any of my
sidecars, & have ridden them solo, with my wife as pillion & empty sidecar, & with
my wife as pillion & my Mother & 2 children in a Watsonian Oxford 3 to 4 seat sidecar.
My current outfit is a Kawasaki VN1600 & Watsonian Monaco single seat sidecar.

Ok and THÁNKS for sharing.
I only bought 2 ready to ride. The others ... a worry

I guess I am rather OCD concerning the asymmetric dynamics
I have per example even calculated speed vs corner radius for rigs
This is btw why I would be VERY hesitant and cautious with a pillion unless the chair is loaded up which in the case of the R18 would grossly over the max vehicle weight.

My reason for ballast is threefold. The first it to improve the weight balance between bike and boot. Next is keeping the rig safer when driving solo. The third is that I want as little as possible difference in dynamics with/without passenger. I think the rig responding to the changing road conditions is enough. I take the ballast out when loading a passenger.

Cool combination you have now. The Monaco is a tried and tested design going back to the fifties if I recall correctly. The VN1600 x Monaco is a wayway more stable, read sensible, combination then my R18 x Velorex. Adding insult to injury I prefer my rig to be narrower rather than wider.


Chapeau to you btw for driving that Oxford loaded up ánd pillion!

 

[R2K]

Saw this on Facebook

 

[Petrus]

Saw this on Facebook

Thanks for sharing.

Looks véry nicely done no money spared. Just look at the lighting.
And the front fork is WOW

About the leading link and trail reducing triple clamps there are two schools of thoughts:

The obvious one is making the steering lighter.
The second is directly resulting from this as making it lighter also reduces the feel. Reducing the forces means also reducing the feed back from the road. Per example about how much traction the tyre has; warning about whether you are on the limit.

I am almost in between towards the side of the latter. I deleted the power steering from my MR2 which I lóve to slide about on/over the limits for that reason. With the rig I want to stay well on the safe side because when things go pear shaped it is even more tricky to control/correct than a mid engine car on a wet road.
Even though sidecar rigs are NOT inherently unsafe, they are asymmetric and thing wíll go wrong very fast if you don´t respect ample safety margins because the unforeseen is a certainty. Shit wíll happen; you just don´t know what/when.

The latter observed I had nicely confirming safety feed back yesterday:
Went to the farm twice. This means crossing the main street of the village I live in. This is a léthal place because of shops at both sides with lost of mostly women double parking and not looking for anything which is directly life threatening to them. Ergo throwing the door open unless there is a bl@@dy huge John Deer about to roll over them.
Also crossing the neighboring village which is typical zigzag through the narrow white house alleys. Anyone exiting such an alley can not see upcoming traffic unless half exiting into the path of said traffic.

Right first time went with the rig. I notice a woman about to throw the door open. Gave her wide birth and she NOTICED the sidecar, halting opening the door!
In the next village akin experience. One car coming from the other side stopped swerving around a double parked car to let me continue. Around the corner a car reverse exiting a garage (even worse visibility than a side street) hastily mover a meter forward when he noticed me.

Second time I was in my car, following a motorcyclist. He narrowly avoid two shoppers then was nearly collected again twice by car drivers simply not seeing him.

The notable difference being me on the rig not nééding to avoid whereas he saved himself four times.
The rig is noticed. Not just by any passer by on the street but most importantly by other road users!

 

[Petrus]

just tripped over an awesomely informative table from a rig builder:

 

[Petrus]

My current outfit is a Kawasaki VN1600 & Watsonian Monaco single seat sidecar.

Thank you for the photo.

It coincidentally illustrates the unfortunate lack of flat tread tyres. I totally understand that the tyre industry cannot justify manufacturing fthese but rigs really benefit from a flat tread hence dedicated special (no traditional motorcycle with bolted on sidecar) builds most times go car rims.

p.s. me with my ODC and fetish for numbers:
The load under my sidecar wheel is only 19% of the total. None too much it is slightly compensated by the 50 kg ballast being on the floor at the outside.
My own weight in the saddle raises the center of gravity of the bike and as such worsens the centrifugal problem in righthanders (tub mounted on the rhs).
A pillion passenger would worsen the situation considerably whereas in the sidecar seat it improves balance.

I have done same exercise for the Nimbus and a pillion worsens the situation even more because the whole rig weighs only 225 kg meaning rider and pillion literally weigh heavy in the centrifugal forces.

Obviously the heavier the sidecar, the less issue.
Yes I am @n@l about the geometry and balance.

 

[Petrus]

here the above build in earlier guise with stock front fork. Also notice no steering damper.