Progress! Sometimes it's a little abrupt. After years of having no time or money to move this project forward, I momentarily had a little of both. I was moving my workshop and had to decide what to do with the Unisport, sitting inside these last several years while I did nothing on the project, while the donor Burgman 400 sat in my driveway under a tarp, not ideal. So I found a local machinist w/ the framing experience I've been lacking, agreed on some details, and got to work w/ a grinder and a short stack of cutoff wheels. My machinist came and collected what was left, and just a couple weeks later (and some fun nights cutting metal and tacking pieces in his shop) I had a rolling chassis!
Sacrilege? What do you think? I've skipped the step of joining the Unisport and Burgman together as Unisport originally intended w/ the bike bolted into the frame. That was always gonna be long, heavy, and unwieldy (and never fit in my much smaller garage). Now, width is moving towards 5' and track is 7.5', that fits my goal of a small, stable vehicle with optional tilt feature. Weight is in the neighborhood of the 440lbs of the original Burgman, with more lightening and some additions to go, performance should be solidly ok.
I've cut up the main body piece, as well. Some day I'll make an enclosed body, for now the goal is a functioning roadster.
It looks like a vehicle now, but there are big steps to go:
- restoring the front clip (ie replacing 100% of the electronics and, cleaning up the metal, and restoring the old linear actuators)
- updating the front hubs w modern discs & calipers
- placing the radiator and gas tank
- connecting the bike controls & gauges & lights
- roll bar, belly pan, seat mounts and rear firewall
What's next? More waiting, really. I've cleaned away all the electronics from the old CB450 so just the tilting circuit remains. Over the winter I'll try to identify and find good replacements for all the components - mostly just heavy-duty DPDT switches that series together two 12v batteries and cross-wire the linear actuators so one side pushes while the other side pulls, plus some limit switches to stop you at max tilt.
Next post will be details of the front clip, I'd love help and feedback here, let me know what you think.
Also, apologies to anyone offended by the slicing up of automotive history - there are much cleaner Unisports out there, though none of them are on the road, these steps get me closer to having the old tech working again.
Friday, August 11, 2017
Sunday, August 29, 2010
Spoke w/ a Unisport distributor
Well I just had the pleasure of talking to a Unisport distributor who was there at the end of the company. He said total production reached about 1500 kits before the 70's economy and a large stock of improperly stored firewalls took the last of the company's resources. Apparently the machine shop making the forward firewalls - the 1/4" steel plates that mounted the linear actuators & centered the tilting parallelogram & steering & lined up the frame, pretty much the linchpin of the design - at the end of production was storing them leaning at an angle instead of stacked flat. A slight bend started showing up and finished cars were wearing out tires quickly. The expense of dealing w/ this problem was the straw that broke the camel's back.
The linear actuators are military issue, from airplane landing gear (sorry not sure which plane), and even have a clutch that's plated off here:
I haven't had much time for the project this summer, but now I have a line to the original circuit diagrams and build manuals - once I've got them I'll get as much info online as I can, & I'll have an easier time replacing the broken old switches.
The linear actuators are military issue, from airplane landing gear (sorry not sure which plane), and even have a clutch that's plated off here:
I haven't had much time for the project this summer, but now I have a line to the original circuit diagrams and build manuals - once I've got them I'll get as much info online as I can, & I'll have an easier time replacing the broken old switches.
Wednesday, April 28, 2010
Where To
The goal of this restore is a drivable vehicle. Specifically, a fun ride for one or two that can handle freeways and rain, but that's longer term. This is a hobby, the project lives in the workshop I run my business from, so when I need a break from work, I'll try to make progress on the Unisport. Here's the plan:
-Step 1: Working tilt circuit-
I don't know how much of what's there is usable, several switches need to be replaced before I can turn anything on. My next post will map out the circuit, then I'll know where to jack in power to test. With the Unisport up on jack stands I won't be putting much load on the system, so I'll replace what's obviously broken, turn it on and see what happens.
-Step 2: Cleanup mechanicals-
Once I see the tilt system in action I can take everything apart and clean/replace. Some things will be updated instead of restored, like the brakes and possibly hubs and wheels, too.
-Step 3: Suzuki Burgman 400 donor
The big scooter donor is pretty capable, but I'll need the Unisport cabin & front clip to weigh no more than 400lbs to run the engine in it's normal range. I'm not too worried - there are a bunch of almost 700lb Messerschmidt & Isetta replicas running 2 people w/ Honda 250cc scooter donors - but I'd like to carry a passenger if I can so I'm curious about the actual weight of the Unisport parts. Rather than hook up the Burgman at the header tube like the original design, I'll slice up the scooter frame to save weight and length.
This biggest consideration is always moving forward, I want this project on the road.
-Step 1: Working tilt circuit-
I don't know how much of what's there is usable, several switches need to be replaced before I can turn anything on. My next post will map out the circuit, then I'll know where to jack in power to test. With the Unisport up on jack stands I won't be putting much load on the system, so I'll replace what's obviously broken, turn it on and see what happens.
-Step 2: Cleanup mechanicals-
Once I see the tilt system in action I can take everything apart and clean/replace. Some things will be updated instead of restored, like the brakes and possibly hubs and wheels, too.
-Step 3: Suzuki Burgman 400 donor
The big scooter donor is pretty capable, but I'll need the Unisport cabin & front clip to weigh no more than 400lbs to run the engine in it's normal range. I'm not too worried - there are a bunch of almost 700lb Messerschmidt & Isetta replicas running 2 people w/ Honda 250cc scooter donors - but I'd like to carry a passenger if I can so I'm curious about the actual weight of the Unisport parts. Rather than hook up the Burgman at the header tube like the original design, I'll slice up the scooter frame to save weight and length.
This biggest consideration is always moving forward, I want this project on the road.
Tilting Overview
Here's a first look at the Unisport's tilting system. Start w/ 2 of the buttons on the steering wheel (R1 & L1 are turn signals); L2 was once a toggle, connecting the ignition switch to the main relay controlling power to the linear actuators, so I'm assuming that's the switch that enables/disables tilting. R2 is a 3-position spring-centered switch (also needing replacement) that moves right & left to lean right or left...
And this is where the leaning happens, w/ the front wheels connected in a parallelogram hinged at the corners. The two linear actuators get power at the same time, so one's pulling and the other's pushing on the base of the parallelogram. Bottom and top horizontals are hinged in the center against the 1/4" steel firewall, so the push/pull creates lean for the body and for each wheel.
The circuit is pretty simple - 5 PRD relays & two "snap switches" w/ piles of dusty goo under them - routing power to two electric motors crosswired so when one is going up, the other is going down.
Thursday, April 22, 2010
General Condition is Better Than Expected
Having had a little time to look over the Unisport I'm pretty happy about the overall condition of things. Lot's of surface rust & degraded rubber & brittle plastic, but much of what is there looks usable.
A big part of this project is appreciating the work of the designers - it's simple and sturdy design, no clutter. With the fenders and wheels off the hubs/brakes are on the heavy side but not as much as I'd originally thought.
The biggest unknowns are old switches (some brittle and broken) and old linear actuators w/o labels (dirty & a little beaten up, will they still work? force, speed, stroke? Who made them?). But overall the restore looks very possible, it's encouraging.
Saturday, April 17, 2010
Unicar Corp Logo
This is the sun-beaten Unicar Corp sticker on the center of the nicely molded & simple dash. I haven't spoken to anyone who's driven a Unisport as an adult, but I know of at least 2 others sitting in garages, and it only took 15 minutes in Illustrator to restore the logo, so here's an oversize JPG:
EPS version in actual size 3/4"X2" is available if you need it. And I have to wonder about the Star Wars theme, very tie fighter, and George Lucas woulda been writing the first movie right about the time Unicar Corp existed... sorry to geek out, I worked for George at ILM for 10 years.
Friday, April 16, 2010
Walkaround Pics
Before getting into the systems in detail, here're a couple photobucket folders full of pics:
a full-frame walkaround -
http://tinyurl.com/y2dyqkx
& a closer view all around -
http://tinyurl.com/y25rr3u
The windshield is missing in these pics, but I do have it for install later. Otherwise you can see in the "clothed" pics that I'm missing the bottom side panels & belly pan (possibly all one piece?). Oh well.
a full-frame walkaround -
http://tinyurl.com/y2dyqkx
& a closer view all around -
http://tinyurl.com/y25rr3u
The windshield is missing in these pics, but I do have it for install later. Otherwise you can see in the "clothed" pics that I'm missing the bottom side panels & belly pan (possibly all one piece?). Oh well.
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