Ariel Plunger Leaner Sidecar Project
"I am looking at designing and building my own
tilting sidecar attached to a special I am
building that has two JAP 600 cc SV engines
set in tandem in a stretched Ariel plunger
frame. Attached are a couple of pictures of
the bike in its early stages. I will be able
to experiment with the firing order to get it
to sound like a parallel twin or V twin with
different angles between the cylinders. The
best power delivery and sound combination will
decide the settings. Can you tell me the size
of the Rod End bearings that are normally
used? The threads look about 20 mm diameter in
the pictures with the BMW outfit. Thanks
Unlike motorcycles, it is difficult to locate
specifications on the Internet when it
Most Ariel motorcycles provide little frame to
attach to. Likewise the BMW on the Kalich
Leaner website has little frame to attach to.
Using Google Translate, the website states a
sub frame is custom made for each motorcycle:
subframe is exactly adapted each type of
motorcycle and different in appearance and
The other examples on ADVRider website, also
have no frame to attach to and a Shadow Frame
was also fitted:
Therefore, it seems you will have to fabricate
a strong Pivit Bracket (Shadow Frame) in order
to attach the Pivits.
The Kalich Schwenker Website: http://kalich.de/html/schwenker.html
states the following:
technique is this necessary? Under the
bike a subframe is attached. Front and
rear of this are backlash-free ball joints
that lead to the sidecar chassis. Because
of the different height of the bearing
points of the side car when cornering
Example ball joints (up to 30mm) can be seen
I am not an engineer, however, while
consulting two engineers concerning our
wheelchair accessible leaner sidecar project;
both had concerns that this ball joint has a
weakness due to being press fit. Also that a
ball joint is not necessary as the motorcycle
will only rotate on one axis. Therefore, the
advice given was that a bush is all that is
required. But your Leaner will be lighter
because our sidecar weighs 140 kgs, the
wheelchair 110 kgs and the occupant 55 kgs.
Even if you did choose the bush option, you
still need a thread to adjust Tow In.
As it is not possible to determine the size
from a photo, if I were you, I would either
contact a manufacturer for specifications or
just go for the 30mm to give maximum strength.
Like me, you probably cannot speak German, so
I would try the Canadian company that have
built Leaner Sidecars:
ask the guys on the ADVRider Forum.
Hope your sidecar project goes smoothly,
I am sorry to hear that your family needs a
Sidecars can certainly be a lot of fun. You
are correct in saying bushes are only required
for a tilting sidecar however the rod end
bearings eliminate misalignment. I have had a
couple of rigid sidecars in the past. The best
was a 1930's Brough Superior 1150 outfit. It
took me many years to restore it. The
chassis acted as an auxiliary fuel tank
holding 1 1/2 gallons. You had to be
stationary and use a rubber hose plus a tyre
pump to pressurise the fuel. I sold the outfit
to a guy in Florida and it has won many shows
in the US.
The bike is a 1934 Brough Superior Model 1150
with a 60 degree 1100 cc side valve JAP
engine. The sidecar is a 1938 Brough Superior
Grand Alpine Sports with the Cruiser body. It
was a pure Art Deco design. As previously
mentioned the sidecar chassis acts as an
auxiliary fuel tank holding 1 1/2 gallons. The
sidecar wheel was fitted with a brake that
operated in conjunction with the rear brake of
the bike. It won many best of shows in NSW and
now in the US it has won numerous best of
show. Regards Terry
Dave attached are the pictures I mentioned.
They came from the BS Club archives.
The first shows an 1150 Brough Superior
motorcycle like mine with a period Garrad
sidecar plus a Garrard caravan. The caravan or
motorcycle van looks like very light weight
construction however it is immense and must
have caught the wind. This was on
the road in the UK for many years and probably
driven to death as it no longer exists
according to the BS Club register. The owners
used it on trips all over the UK and took
their numerous pets with them including cats,
a cocker spaniel and a ferret all together on
trips of up to 200 miles. Only the English !
The second group of pictures shows a double
adult sidecar attached again to an 1150 Brough
Superior like mine. The sidecar is bigger than
the bike. Apparently the four passengers
enjoyed numerous holidays together. This
outfit no longer exists either and was
probably driven to death. I can't imagine
riding four up the weight would have been just
too much for safe motoring. Cheers Terry
I looked at some rod end bearings recently in
a bearing suppliers. I was surprised to see
there is end float within the bearings. The
supplier explained that is normal and there
must be a certain amount in all of them for
normal operation. A bit too much movement for
me. With two of them basically in line the
sidecar would tend to pull back on
acceleration and push forward during braking.
I guess brass bushes are the way to go and
would be in keeping with the age of my bike.
When you think about it mounting a sidecar
rigidly to a bike is the worst thing you could
do to a bike frame.
I had been thinking independently about a
banking sidecar for years and figured two
pivots below axle height was the way to go.
Having the front pivot higher than the rear as
mentioned in your web page is an improvement.
Nice to hear from you.
I agree. I love the way the sidecar wheel is
steered rather than scrubbed as it turns the
corner. Thanks to the higher front mount. I
would so love a leaner.
This video is my favourite.
Hey imagine if the leaner sidecar was a
The passenger could have some "non
operational" handlebars. Don't think it's been
done yet. Would be handy for a motorcycle
instructor and student.
I'll put the feedback about the Pivot Mounts
on your webpage.
Maybe they are a bit light for the type of
work they will be doing.
Join the conversation. Chat on the Haul N Ride where
sidecar and trike enthusiasts can share thier
passion with others:
See Photos and a Detailed History of the
Brough Superior and Sidecars. Click Here
Terry's project updates will be added when we