# motorcycle with sidecar



## Woodsmith (Jun 5, 2008)

Sounds like a good plan.

I think the car rear axle would make it easier but it depends on if it gives you the ratio you want. 

Using an IRS axle would mean the motor and diff can be very close coupled as it would only have a tiny range of relative movement. A rubber doughnut joint would probably be fine. Or you could rigidly couple the two together.
Hmmm, a 2CV transaxle with a small motor would give you gears too....

You could also then look at the option of mounting the motor above the IRS diff and belt/chain driving the diff pinion to get the best ratio. It moves the weight up a bit but that can be compensated for by keeping the batteries low and centered towards the rear.

Are you looking at a complete scratch build or do you have a base vehicle you are going to modify?


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## tchapin (Feb 2, 2011)

I also wondered about the sidecar approch. At least for battery storage. I then got to drive my neighbors Ural. It is one of those WWII bikes that are still made pretty much like they were in the 1940's. Fixed sidecar bikes are a real pain to "drive" (not ride but drive). The whole motorcycle experience is gone. No leaning into curves and you better know what you are doing when you do have to turn or you will end up in the ditch. I have seen leaning sidecars. Looks pretty complex but that would be the only way to go (imo). The fixed axle would just be more of the same as far as turning. Maybe another approach would be reverse trikes.. Single wheel in the back t wheels up front.


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## PaulinWA (May 19, 2013)

I like the idea and please bear in mind I am brand new to EV building but not trike building. After fixing the sidecar as permanent wouldn't it be easier just to build a trike? Like you mentioned a reverse trike. A reverse trike is MUCH lower to the ground and would recover some of that motorcycle experience you lost with a hard mounted sidecar. I have driven a reverse trike and they corner like they are on rails. Aftermarket VW front beam is a cheap way to go, if you look in kit car clubs forums or thesamba you can find fiberglass front clips to a host of kit cars you could use as a front end.


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## vmrod (Jul 2, 2010)

I'll have to provide my reverse trike link for fun...

http://xr3.proboards.com/index.cgi?board=diary&action=display&thread=19


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## mizlplix (May 1, 2011)

The thought was for the motorcycle/side hack look.

If I were to build a good looking and handling light weight vehicle, I would do a Lotus 7 (locost).

Way back, I raced hacks. It was grueling and required a good bit of body English, (please forgive the term).

Miz


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## HaclD (Jan 3, 2016)

Hi there:

First post and all that.. this thread caught my attention in a first google search on EV's, specific to sidecar rigs. While it's quite old, dating back to 2013.. it's worthy of a dead-thread revival (I hope) with some input.

For back-ground info, i'm an affirmed petrol-head, with experience on 3 different sidecar rigs over 25 years. 2 were your usual 'universal japanese motorcycle' bolted onto Jawa tubs, making them light-weights unsuitable for major changes from an economic perspective. My latest, is a heavyweight 1200cc sport-touring conversion using a 1980's Hannigan enclosed touring sidecar. A bit of an odd match at the time that took a lot of re-engineering and rework (it's no longer possible to be a solo motorcycle again), but it was a lot of fun. It's been off the road for a few years now due to health issues.. but i'm looking at reviving it - as such already being 'custom' and now with relatively high miles, an all-options open rebuild is a possibility. 












mizlplix said:


> Hi, Miz here:
> 
> I was brain storming the other day and came up with an idea I felt had merit.
> 
> A motorcycle/sidecar built in one piece. (the sidecar is not removable.)


Your photo is missing, unfortunately .. i can only guess at which one(s) you are referring to - I am familiar with the types that are of monocoque construction - dedicated, road-going, sport-sidecar rigs with a custom car-based running-gear, suspension, hub-centre steering, fabricated frame with fully integrating bodywork between 'bike' and 'sidecar'. High-dollar items, definitely.

From my perspective, i'm going to be answering these, based on my own experience and now somewhat dated knowledge based upon my own heavyweight sidecar project. 



mizlplix said:


> It opens up a world of possibilities:
> 
> 1- mount the motor IN the sidecar. Down low and transversely, with
> the drive end facing the motorcycle side, so the chain/belt drive can be
> ...


A couple of issues with this - 2WD in a sidecar rig is problematic. 

- Space - even with a large side-car, is at a premium. A sidecar rig, with a proper asymmetric setup (correct sidecar wheel lead, toe-in) will generally have the passenger directly in the way of any transaxle setup. There have been very elaborate gear and shaft indirect drives devised for a few, but they are both complex, and power robbing - and almost invariably, custom one-offs to produce. Throw in a motor, battery tray AND a drive-shaft/transaxle arrangement for 2WD, and you are raising the CofG of a passenger sitting on top of all components.

- Complexity - an asymmetrical, road-based, sidecar rig needs to be built on the KISS principle. There isn't much benefit to 2WD for street-based sidecar rigs - proper asymmetrical setup, with the ideal rake/trail figures designed into the front end of the sidecar rig, compensates for any rolling-drag coming from the sidecar corner of the suspension setup. 2WD would make a lot more sense on sport adventure setups, and of course factory 2WD has it's place in Dniepr/Ural based designs - they are the low-speed sidecar equivalent of a John Deere Tractor - and not particularly well designed for a higher-performance EV setup. Ideally - keeping the motor inline with the rear wheel reduces overall complexity, and improves efficiency. 

- Balance - a sidecar rig needs to be balanced, with proportional weight on each of the three angles of the triangle. Put too much weight into the sidecar rig, in addition to a passenger, and handling/braking issues are going to be introduced into the equation. Keeping the weight *down* on a sidecar rig, and keeping the whole rig 'flat' in terms of overall suspension movement - especially in pushing the performance envelope, is all important. If the sidecar rig becomes heavy on the front end (lightening the rear end and sidecar wheel) during a higher speed corner, it's in danger of spinning out. Overload the sidecar wheel by causing CofG to shift over to that corner of the triangle, can cause partial steering loss as the sidecar wheel 'skips' against traction laterally. Having the sidecar 'lift' due to handling or an unbalance is never a good thing. Too little weight over the rear wheel .. that one's a bit obvious. 

Dedicated sidecar rigs like these tend to use bespoke hub-centre front steering setups, variations on swaybar linkages to connect sidecar wheel to rear wheel, and run automotive rims/tires. 



mizlplix said:


> 2- that leaves the flooring of the "hack" for batteries as well as the
> whole motorcycle frame area.


Ideally, yes - sidecar storage places are the ideal spot for battery packs - you can ideally dedicate a few cubic feet for a battery pack AND fit a passenger.



mizlplix said:


> By having a solidly welded frame and sidecar structure, it be really
> solid and would look traditional while being Avant Garde at the
> same time.


You can go that route - but if you are looking at the rigs i'm suspecting that you are looking at - they are quite high-dollar to begin with. You can also retro-fit an existing sidecar design setup, as long as setup and modified to intended use, from the start. 

The Hannigan sidecar design (or similar), matched to a mid-weight or better motorcycle chassis would be an excellent basis. A lot of custom work would be necessary to make it better than a design compromise. 



mizlplix said:


> Of course it could use a single sided swing arm, as well as a single
> sided springer at the front, that way all three tires/wheels would
> be identicle and easy to maintain.
> 
> ...


Look at what those involved in the sports sidecar scene are doing for overall suspension, steering and wheel setups. A lot of engineering needs to be done, and a lot of ideas that can be adapted and refined upon.

An example:

http://hpsidecars.com/WebAlbums/Past Pictures/index.html


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## ken will (Dec 19, 2009)

If you keep the weight low and use the clutch lever for the side car brake, they handle pretty good!


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## evforme? (Jul 23, 2015)

I had a similar idea, but for me I planned to build a rather standard ebike from an 80s Kawasaki twin with short to moderate range and make a removable side car that would give a 200 or 300% battery capacity boost for longer hauls.


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