carcentric
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| posted on 29/1/06 at 06:33 PM |
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The CARCENTRIC Trikester
This has probably been done a million times, but I woke up at 3:00am and had to get up and PaintShopPro it.
See concept here
M D "Doc" Nugent
http://www.carcentric.com
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Chippy
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| posted on 29/1/06 at 11:27 PM |
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Hmmmm! think it needs a bit of work, like maybe a complete rethink.
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Peteff
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| posted on 29/1/06 at 11:37 PM |
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Yup!
I think I'd have turned over and written it of as a bad dream as well  .
Do you really hate the bike that much.
[Edited on 29/1/06 by Peteff]
yours, Pete
I went into the RSPCA office the other day. It was so small you could hardly swing a cat in there.
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Triton
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| posted on 29/1/06 at 11:39 PM |
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But it's a CX .......
My Daughter has taken over production of the damn fine Triton race seats and her contact email is emmatrs@live.co.uk.
www.tritonraceseats.com
www.hairyhedgehog.com
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RazMan
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| posted on 30/1/06 at 09:52 AM |
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Didn't Stimpson do something like this?
Cheers,
Raz
When thinking outside the box doesn't work any more, it's time to build a new box
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Spyderman
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| posted on 30/1/06 at 05:43 PM |
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Think I'd rather keep the bike as it is!
Spyderman
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carcentric
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| posted on 30/1/06 at 06:45 PM |
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Sorry, gents, the old CX won't stay a bike. My diabetic feet can't keep me upright at a stop any more, so I gotta be free on three!
Riding the Trikester would be very similar, I imagine, to sitting on a scuttle-high, padded console between the seats of your Locost (windscreen
removed, helmet on) except you have a handlebar instead of a steering wheel. And it'd be a lot lighter. What's missing behind you (the
4th wheel) won't be noticed unless you're backing up.
Now put your thinking caps back on and critique the build issues, please.
It's either the Trikester or going "American trike" (1F-2R layout) like this:
(click HERE for that page)
I don't want a "sit in" trike - even without a steering wheel and side-by-side seats, those don't tend to be registerable as a
bike/trike over here. The authorities refer to them as cyclecars and start requiring automobile specs and equipment . . . .
M D "Doc" Nugent
http://www.carcentric.com
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smart51
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| posted on 30/1/06 at 07:25 PM |
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I can see where you're going. The flared wings are a bit 30s in design whereas the bik is more 50s. Keep the halves a bit more coherant and
you might have something. A chrome bike but with 2 front wheels.
Handlebar steering without any lean. Will that be a bit twitchy? You might get a lot of turn for not much hand movement.
I say stick with it, but work on the front.
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carcentric
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| posted on 30/1/06 at 08:35 PM |
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Thanks, '51. Rorty's Hammerhead was a key inspiration for me (especially the steering method), but I'd rather go '30s (e.g.,
Locost roadster) style with both the front/lower half and top half. Considering that, what would tying the two together (visually) require if the
'30s look was the goal?
Painting the chrome (probably black) is easy, and I could fair the tank into the body so it looks more "of one piece," but what else needs
tweaking?
None of the Morgans I've seen have "sit on" designs - they were clearly meant for people who wanted, but couldn't afford, a
car. If there was a tadpole trike of that era, though, it might help me to see it.
Or is it just too long? This is exactly the same as my first Trikester except for the length:
[Edited on 30/1/06 by carcentric]
M D "Doc" Nugent
http://www.carcentric.com
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RazMan
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| posted on 30/1/06 at 09:07 PM |
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I know what's driving you now - I'm an ex biker (had over 30 bikes all over 1000cc) and have had my biking days numbered by a dodgy back,
which is a legacy of some extreme sports which went .... a little too extreme.
I had a thought about a similar conversion to my last Goldwing. Like you I didn't want a sit 'in' trike but wanted to keep my knees
in the breeze. Some of the US Wings have been 'triked' in typically American style with a live axle and diff nailed on the end of the
shaft drive (which of course the CX has) These look really good when done well and the handling is suprisingly good too.
As for your proposed 'two up front' idea, the steering will be the biggest challenge IMO and you will have to introduce some kind of
cantilever arrangement to reduce the handlebar 'lock to lock' gearing or it will rip your shoulders out of their sockets 
Cheers,
Raz
When thinking outside the box doesn't work any more, it's time to build a new box
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carcentric
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| posted on 30/1/06 at 09:42 PM |
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quote:
Originally posted by RazMan
. . . As for your proposed 'two up front' idea, the steering will be the biggest challenge IMO and you will have to introduce some kind of
cantilever arrangement to reduce the handlebar 'lock to lock' gearing or it will rip your shoulders out of their sockets
This is Rorty's Hammerhead design
(http://www.rorty-design.com/content/Hammerhead.htm). While not easy to see, I
don't think there's a steering rack (or recirculating ball gearing) at all. What I think it uses is a simple lever off the steering shaft
with tie rods going to each wheel hub directly (at roughly right angles to the steering shaft lever, they're orange in his CAD drawing). The
length of the steering shaft lever (relative to the handlebar width) would provide whatever mechanical advantage you'd get. I don't know
what size wheels/tires his uses, but with 13" car wheels/tires, a steering stablizer (shock absorber) is probably needed.
In addition to that, what would your cantilever arrangement include?
[Edited on 30/1/06 by carcentric]
[Edited on 31/1/06 by carcentric]
M D "Doc" Nugent
http://www.carcentric.com
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RazMan
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| posted on 30/1/06 at 09:58 PM |
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Hmmm I can't quite see how the steering linkage works in the pic. I'm probably using the wrong terminology - maybe a progressive gearing
setup is more appropriate? I'm thinking of a compromise between normal road use (when very little bar movement is required) and parking
manouvering (lots of movement) A normal rack would require maybe a full turn or more to achieve lock to lock - obviously impractical for a handlebar.
Direct steering would be too much of a strain keep everything in a straight line.
I can still remember the consistent pull of my Bonneville / Squire sidecar when I went to the IoM TT - I had huge arms in those days! 
[Edited on 30-1-06 by RazMan]
Cheers,
Raz
When thinking outside the box doesn't work any more, it's time to build a new box
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smart51
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| posted on 30/1/06 at 10:41 PM |
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I think you mean a variable ratio steering box (or rack). movement of the handlebars near the centre produce small turns in the road wheels for high
speed lane changes, the same movement in the bars near full lock produce large movements in the road wheels, for parking or tight corners.
As for 30s styling, bikes were spartan and cars flowing. I'd think about a "streamlined" snail shaped rear mudguard like the rear
wing from a 30s car. perhaps make the rear wing wide with a very small cut out like a vespa.
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carcentric
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| posted on 30/1/06 at 11:05 PM |
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I haven't done the math (steam engine geometry), but a watt's link does some of that in that the push/pull motion drops off as the link
prepares to change direction.
The quick and dirty solution would be to make the steering safe for typical speeds and just live with insufficient turning whilst parking, but
there's probably some way to do what you propose without adding a power steering pump.
Here's a "closeup" of the steering shaft lever I referred to:
The longer the lever, the more "twitchy" the steering would be at high speeds (and the more effort it would take to park).
The shorter the lever, the more stable it would be at high speeds (and parking would require much sawing fore/aft to make a tight turn).
M D "Doc" Nugent
http://www.carcentric.com
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Peteff
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| posted on 30/1/06 at 11:10 PM |
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Rorty's designs.
Did you ask Bob before posting his pictures? Just a thought about common courtesy.
yours, Pete
I went into the RSPCA office the other day. It was so small you could hardly swing a cat in there.
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RazMan
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| posted on 30/1/06 at 11:13 PM |
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Ah I see it now.
A certain amount of leverage can be dialled in but to make it progressive would definitely mean introducing a variable ratio gearbox as Smart51
says.
I'm a bit out of touch with motorsport nwadays but what do the quad motocrossers use? They must encounter similar problems.
Cheers,
Raz
When thinking outside the box doesn't work any more, it's time to build a new box
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carcentric
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| posted on 31/1/06 at 12:29 AM |
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And if straight line stability needs to be increased, add in more caster, correct? I see racing karts use 12-15 degrees (compared to the typical 6
degrees of a car).
That'll increase high speed steering effort IIRC, and is easy to do during the frame build (rock back the front suspension towers).
[note to Peteff: I emailed Rorty a couple days ago to share my first thoughts and thank him directly for inspiring me. I haven't received a
response yet, but will ask if he minds us using parts of one of his drawings to further this discussion. If he has any reservations, I'll
delete his work from my posts.]
[Edited on 31/1/06 by carcentric]
M D "Doc" Nugent
http://www.carcentric.com
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Peteff
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| posted on 31/1/06 at 10:48 AM |
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I'd rather see the naked look with just a top fairing. Covering in the engine on an old bike will probably make it run a lot hotter as well.
Just stick a sidecar on it if you can't ride it on two wheels, that's what we did with my mates Goldwing (he's minus 1 in the leg
department}
yours, Pete
I went into the RSPCA office the other day. It was so small you could hardly swing a cat in there.
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blackbart
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| posted on 24/4/07 at 07:37 AM |
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Carcentric Reverse trike
I think your Idea is neat your just in the wrong place. The place to be for what you want to do and the help you need is a site called
reversetrikes.com There is a V8 trike similar without the fender flares. I have modified Ron Champion frame on a Honda Gold wing. You do need to have
a wider wheel track for the length you are looking at though for stability. 40 inches wont do the basic formula is two thirds the width, front wheel
track, to length.
Dont let the nay sayers stop ya. jus t join the right brotherhood.......yee ha better on three ....you can eamil me if you need other
info.....
 
Rescued attachment V8 Roadstercycle.jpg
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Peteff
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| posted on 24/4/07 at 10:07 AM |
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I can just imagine a CX500 trying to pull that lot round 0-60 if you're lucky? They weren't exactly blessed in the power department. I
like the two up front trike but it needs something more than 30 something hp. Here is another trike site to join.
yours, Pete
I went into the RSPCA office the other day. It was so small you could hardly swing a cat in there.
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