Fully fabricated and highly customized CH250

Starting with a donor engine from 1985 Honda Elite CH250
and married it to a stretched and lowered  CN250 frame.
I used the rear engine mounting frame, but lowered the seating position by 8 inches.I also incorporated the front suspension and steering shaft but stretched the foot pan by another 18 inches and moved the gas tank from under the seat to the foot pan, as it was in a Helix of the same year

I started the build up the overall shape with sheets of high-density styrofoam, purchased from the local building supply. By laminating the sheets together and able to achieve the thickness needed. First carving away the excess foam with whatever cutting implements which were handy.
Once the shape was roughed out it was time to search the local art stores for plasticine… lots and lots of plasticine!
Over the weeks and months I carefully defined the overall shape and began to incorporate the idea of access and panel management at this early stage.
First I needed access to the modified electric panel, which was to be located in the front below the headlight light and above the rad.
I also needed access to the fuel tank and battery and finally the rear section for electronics and access to the rear signal lamps.
These pictures show the progress after the first summer and heading into the fall. It was slowly coming along, but the tank shape and placement was still up in the air.
I had briefly toyed with the idea of an old fire extinguisher, but the amount of extra work wasn’t worth the effort to have it legally certified.
I eventually decided to keep the Helix tank and mount it in the same location, on the floorpan

There were several complicated steps that all needed to be completed before I would have a finished piece ready to cast. I decided to do them in three sections. Front, middle and rear panels. The front panel would have to be two pieces as access was required to the electrical junction box and radiator, plus… the sides had to be mirror images of each other… not an easy task for a homeschool DIY.
Many templates and measurements later and satisfied with the accuracy of my mirror images, I was finished casting each of the sections, ready for molding

Now the hard part!
Two casts are required to get the final piece.
First you cast the negative from the mold and then you use the negative to cast the final piece… that was a lot of fiberglass and resin, luckily I stumbled across a local boat builder and he supplied me with all the fibreglass, resin, hardener and release that was required.

The original idea was to build a steampunk themed scooter and had decided early on not to use any chrome, choosing instead to use wood for the running board and then replacing all the chrome features with hand cast brass.

The problem with casting in brass is that I wouldn’t be able finish the body of the Helyx until the beauty pieces were final cast, as each of the pieces would shrink a little in the actual casting process. The precise amount of shrinkage wouldn’t be known until we actually had them polished and in hand.

Getting into the summer of the first year and the brass pieces are back, raising another casting problem… I had to make custom LENSES and mounting plates for the bulbs.
Using a clear acrylic and adding the colour that, closely, matched commercial signal lenses.
Getting down to precision measurements here and taking a lot longer than expected, but the results were gorgeous and the final result turned out better than I could have hoped for.
The seat was done by the same shop that had done the upholstery for my 61 falcon. Their craftsmanship was impeccable and the seat turned out perfect.
The paint job was done in the garage and a custom colour that I had mixed up for me. It appears darker in the shade and sparks up with copper tones in full sunlight, flawless.

Bodywork completed, lenses cast, engine rebuilt, including new pistons, rings and honed cylinder.
New rollers, new carb and it’s time for a custom exhaust.
I went with an exhaust from a CR250 and played with the shape of the pipe. Because of the location of the exhaust port and hanger position for the muffler, it was necessary to come up with a rather shapely exhaust down tube.
The sound! Very throaty and with the reducer plug removed it’s just loud… so it’s going to stay in.

I was only able to ride it a couple of times as I discovered a front suspension problem and frustrated put it back into the shop, where it sits to this day.
My long, long term goal is to fully convert it over to a 3000w electric motor and get it back on the road over the next couple of years.
Helyx isn’t dead, just E-volving.
Thanks for reading

The CH250 was one of the most exciting 250cc scooters ever made
The CH250 was one of the most exciting 250cc scooters ever made
I eventually decided to go with a fuel tank from an “84 Helix
Top: Along with the custom rear signal light mount, these eyebrows were also custom cast solid brass.

Left: The hand cast original fiber glass shell is finally ready for paint
Helyx is ready for the first ride.