Jago Swizz
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| posted on 7/2/07 at 11:36 PM |
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A mate of mine builds fwd three wheelers with bike engines. He's retired and does it as a hobby basically, and manages one a year. The last one,
and the latest nearing completion uses a Moto-Guzzi engine mated to a Citroen 2CV gearbox. He aims for a weight of around 420kg to gain motorbike SVA
classification, and only reqs a bike license to drive them.
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Ratman
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| posted on 9/2/07 at 11:45 AM |
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Sound like just the ticket. Are they like the old Morgan, or more inovative in general layout? Any pix? I was sort of hoping to be able to use the
bike gearbox to get that tasty 6 speed sequential shift that bikes all seem to have these days.
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Jago Swizz
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| posted on 22/2/07 at 06:01 PM |
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Hi Ratman,
I'll sort a few pics & post them asap.
Swizz...
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akumabito
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| posted on 23/2/07 at 11:35 AM |
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Well, there's more 2CV based kitcars around...
2CV-based kitcar club website
From their site:
Le Patron, Cygnus, Dauville, Manx, Pembleton, Lomax, Charon, Voglietta & Burton.
The Pebleton is my favorite, especially the 4-wheel version, the Pembleton Brooklands. With the BMW flat-twin conversion that car looks and drives
great!
Pembleton website
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Jago Swizz
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| posted on 23/2/07 at 07:58 PM |
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Here it is:
This was built with 2cv engine & box - the guzzi engine being added after, which is why it looks a bit 'added on', as he had to chop
the bodywork about a bit with the v-twin.
His latest, which is nearing completion also uses a guzzi engine/citroen box & has the bodywork built to suit so looks really good.
They are both single seaters, weigh very little due to a new chassis & coil/shock suspension & really fly
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Ratman
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| posted on 25/2/07 at 10:16 AM |
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Thanks Jago
I'm interested in any others similar you know of.
Cheers, Brian
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boxsterund914
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| posted on 16/3/07 at 04:24 PM |
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Interesting topic. I just went out to the garage and pulled out a five speed Porsche 914 gearbox (901) that I've had sitting around. I pulled
this box out of my 914 when I converted to a Chevy V8 with a Porsche 930 turbo gearbox.
I think that this box would work well with a Harley Davidson motor doing a little front drive Morganesque type thing. Vintage looking with a
twist...what do you think?
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3GEComponents
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| posted on 16/3/07 at 04:33 PM |
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Here's my favorite, rwd, but cool none the less
 
Rescued attachment sub2.jpeg
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wilsongt
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| posted on 21/3/07 at 02:54 AM |
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Hill climb trikes
Hello Brian,
I take it you have seen these FWD Trikes? (images hopefully attached)
The only other bike engined FWD trikes I know of are:
1. Lomax - Supa Vee and Guzzi variants
2. Pembleton
3. A mid-80's US one-off which had a Yamaha Virage v-twin motor arrange a la Morgan. Beacuse that bike has shaft drive, it was then a chain drive
to the diff. From memory the builder used the gearbox/diff from a FWD car
I think most of these have already been mentioned by others
My 'in head' fanatsy FWD design has always featured a v-twin like a TL1000 or Aprilla. The other key feature being inboard front brakes. So
that means either the motor out front like a Morgan, with a connection from the output shaft to something like a Citroen GSA or an Alfasud
diff/gearbox, or else out front (crank parallel to axle line) with chain drive to a diff with inboard brakes.
The weight out front is not an issue in my opinion, given you as the driver weigh more than the engine...but the aesthetics could be. To lower the
bonnet height you could always move the motor behind the front axle line, but then you start to take weight off the front wheels, which is not so
good. And there will be sprockets and support bearings and chains all over the place.
Alternatively - how about AWD? Have the motor behind the front axle line, but driving all 3 wheels? Allows for skinnier tyres, lower bonnet line. But
adds complexity, and the need to make the chassis stiffer to keep that driven rear wheel in place
Regards
Glenn
 
Rescued attachment hc_trike1.jpg
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wilsongt
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| posted on 28/3/07 at 10:58 PM |
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Another website
Just to let you know you are not alone...
http://www.clevislauzon.qc.ca/Professeurs/Mecanique/ethierp/3-wheels/index.htm
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Ratman
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| posted on 30/3/07 at 10:39 AM |
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Glen, buddy, thank God, there are others out there. Huge relieve.
How about using the early 1600/1800cc subaru 4WD mechanicals, but putting a motorcycle shaft drive rear wheel onto the end of the rear drive shaft.
Find the right sized wheels to suit the resulting gearing. This early scooby engine has good power for it's light weight and the later ones are
single OHC and turbo to boot. 125hp or so I believe. These don't have inboard brakes... but the hand brake works on the front wheels, which is
handy for a 3wheeler as there is not much weight on the rear wheel. the only major challenge is to change the front suspension from strut to
something else.
Brian
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CGILL
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| posted on 18/4/07 at 06:01 PM |
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Hi,
Having grown up with minis, I know how much fun it can be with all the weight on the front wheels driving, and the rear end tagging along, so this
idea has always interested me. I've been drawing up ideas for some time now, as we have a huge choice of lightweight fwd setups avail in NZ, I
was looking at a transverse set like a swift GTi or mazda mx6 v6, for the main reason that the tail of the gearbox wouldn't intrude into the
cockpit area as a subaru would, and with the height of the crank in the subaru there wouldn't be too much difference in the cog. I'm
looking at a making a backbone chassis from 1" rhs and round tube for diagonals, with outriggers to at the rear to hold a cockpit tub that would
be glassed marine ply, the outriggers would give me fixings for belts etc and the ply tub would stiffen up the whole thing and add some protection. I
think the great thing about this setup is that as there is no diagonal weight transfer across the chassis as such, it will not twist like a 4 wheeler,
and the weight transfer either piviots across the front axle lie, or side to side at the front, so effctivly a very rigid chassis without being all
that heavy. For the main body I'd use segments of flassed foam for the lightweight aspect, and try and use the donor front struts to make it
easily serviceable, hopefuly the height of them can be absobed by the topers lining up the where the a-pillar would be at the bulkhead. I plan on
doing an open top, canam style. The rear end will be from 3mm RHS, and using the rear stub of a fwd corolla (they bolt on with a flat 4 bolt flange)
complete with the brake, utilising the handbrake aswell, I was thinking of using a rear brake regulator off a van, the ones that restrict the pressure
dependant on load, and lever this off the rear trailing arm to avoid lockups and still pass as having a rear brake, similar to a mini, but in a
warrent station on the brake roller, there will be no weight transfer to the front, the rear will still be low, and so the regulator will be open for
a strong brake, while on the road with slight tail lift the pressure will be throttled back.
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WanchaiWarrior
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| posted on 19/4/07 at 01:26 AM |
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Perhaps its just wishful thinking, but would it be possible with some thought to convert the back end of the MK Sprint R to a single wheel, perhaps
chop off part of the back end a reshape the chassis ???
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Clubmanic
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| posted on 23/4/07 at 11:37 AM |
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Fwd bike trike
The Berkely probably was/is the definitive example of parallel twin cylinder bike-engined front-drive installation, was produced in four- and three
wheeled forms.
Today, though, hooking up a BMW or Guzzi twin to an Alfasud/Subaru/Audi/Renault fwd transaxle might be a better proposition.
Front-drive has several advantages for three-wheeler. Two wheels up front is inherently the more stable layout; concentrating the mechanical mass at
that end furthers the stability aspect; and front-drive (with an open diff) confers an element of roll-over inhibition because if the machine
lightens, let alone lifts, the inside wheel, the outer wheel is robbed of torque to the detraction of cornering force.
But bear in mind that the vagaries of front-drive may require more sorting (then with a rear-drive car, for example) to avoid torque steer and other
nonsense. Anyway, an interesting adventure.
Pls keep us posted about developments.
Cheers
Clubmanic
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Ratman
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| posted on 29/4/07 at 11:42 AM |
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Thanks CGILL for sharing your thoughts and plans. I'm not sure that the requirement for torsional stiffness in such a vehicle is that much
lesser than for a 4 wheel car. In a 4w car, low torsional stiffness can mean that the car flexes and the suspension will not work properly unless it
is much softer than the chassis. In a 3w car, poor chassis torsional stiffness might not be so critical to suspension, but because the moment caused
in cornering by the C of G being a certain height above the ground can only be resisted at one end of the car, the car can actualy twist and the
single rear wheel lean over if there is not enough torsional stiffness. Only 1 or 2 degrees of twist is very noticable and looks awful. This picture
demonstrates this problem..
As discussed above.. using a car transmission , e.g. Renault, has conveniences, but I really like motocycle gearboxes for their lots of gears and
close ratios.
One problem is that if you have light weight construction and an engine (and transmission?) ahead of the front wheels, you have to have all the weight
very close to the ground to avoid the risk of standing the car on it's nose in hard braking. I was thinking of making the car extra long and
with a back seat, in part, so that this problem can be addressed. I have been using 1G as a design value for braking resistance in these
calculations.. is this reasonable?
Some models of Fiat car have that same sort of rear brake pressure limiting valve that is mentioned above.
.. Brian
[Edited on 29/4/07 by Ratman]
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CGILL
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| posted on 30/4/07 at 05:49 AM |
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Hi Brian,
One unit that I looked at for a driveline, was the engine and box from a subaru ace van, it's transverse, and in the van, the engine is in the
back - behind the rear axle, it is also mounted on a canter to give a lower deck height. I was thinking in a 3 wheeler setup that the engine being
behind the front axle and low would prevent bringing back memories of front wheel stands on BMXs from front braking... haven't layed out boxes
and seats to see what the legroom would be like though. 
It's a little 3 cylinder 1000cc, but I'm sure with a small turbo it could be made scarey enough.
Perhaps a bike engine could be used and drive a chain driven quad bike diff, or a sierra like drive coupled to the bike output through a CV to take up
movement (was thinking of the CV in the middle of driveshafts as used in commodores, SD1's etc.
Was looking at a backbone similar to this www.spydercars.co.uk/practical_classics_pg1.htm
I believe the doran is similar, but looks like its made from huge sections of rhs fron the few images I've seen.
Seeya
Chris
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Ratman
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| posted on 30/4/07 at 08:09 AM |
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I was looking at one of those vans... a pick-up version actually... just last month thinking about it's posibilities. Hadn't thought of it
as a FWD donor, but you're right. That would work well. I have some reservations about gear ratios. It's nice to have lots of gears but if
you take a power unit from an "underpowered" vehicle it is bound to have wide spaced ratios, and this means one or two low gears that you
never need to use in a lightweight car.
Seductive as they look, I'm not a fan of backbone chassis. It seems a bit redundent. You still have to build a structure to protect the
driver... so why not make it the main chassis as well. The only downside of this thinking is if you want an open car with doors. Then a backbone is a
handy solution.
I was wondering about side mounting motorcycle V twin just behind the front axle and offsetting the driving position a bit to one side to balance the
weight. drive could be by chain either to front or rear. This gets all the mass close to the front axle.. ??
Cheers, Brian
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CGILL
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| posted on 4/5/07 at 03:38 AM |
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How about mounting the center of a subaru viscous diff between sealed bearings, fitting the toothed gear to where the crownwheel gear bolts...
although I'm not a fan of LSD on fwd, it is a sealed unit.. and a vtwin behind this centrally between footwells so the chain drives forward to
the diff?
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Ratman
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| posted on 5/5/07 at 08:27 PM |
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Yes.. I like that option. Cooling might be a problem. Maybe use a watercooled v4 like a Honda VRF*** .chain drive could add to the width of the power
unit a bit, but you could just add more front wheel base for that, or use up some passenger side footwell area.
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CGILL
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| posted on 6/5/07 at 01:28 AM |
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A leaf blow fan attached to the crank? lol....
Was thinking that as the foot wells will be lower than the scuttle, there would be a gap between the bonnet line and the top of the foot wells of
about 6-8 inches, the vtwin between them, an undertray that ducted air from the front under the motor, up, and out the sides of the bonnet, would
probably need an electric fan for when not moving, but still a bit of a worry for the bottom of the rear cylinder. I wonder how much flow you could
get through a trans tunnel .
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CGILL
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| posted on 6/5/07 at 01:35 AM |
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Also thought worth a mention, the subaru rear diff splines are the same as the front, so the struts can be cut down, and top hatted to provide
uprights and axles that will plug in nicely, subaru rack is infront of the hubs, and with the rack with power assistance removed would give a neat
pseudo quick-rack .
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Ratman
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| posted on 6/5/07 at 10:50 PM |
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That is very usefull information. Thanks for that.
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