Southie

I fully retired in April 2025, and was searching for a project when I came across ‘Cycle Karts’. Love the idea. Raced enduro motorcycles in my youth and rally cars in middle adulthood. 
My thoughts: wanted a period correct build with front and rear suspension, and wanted roll-over protection without an ugly roll-hoop. Also wanted the challenge of front engine, rear wheel drive, and low seating height. I’ve built stuff before - usually with a basic drawing and then straight into manufacture. This time I decided I’d learn to use CAD and do a lot of planning before getting out my MIG and grinder. Onshape is a free modern CAD cloud-based tool and I’m slowly learning to use it. I have verified my basic packaging and have begun accumulating sources for materials and have purchased some of the parts.
I initially hoped to purchase a CAD file of the W154 body and re-scale it, but all I could source were STL files which I couldn’t scale - so I had to start from scratch.  It’s certainly interesting learning new skills. 

My first purchase was a brand new Honda GX200 - sitting unstated, with no oil or petrol to date! I think I bought it as a sign of commitment. Basic body shape is pictured on my profile page - the crest behind the cockpit is too high and I’ll have to redo it. That in itself won’t be easy, as a lot of the shaping was done in my very early Onshape adventure, and I don’t think I can undo it. Hopefully it will be easier the second time around. 
My plan for the next step is to start a mockup of the basic frame and chassis in wood (I don’t want to keep cutting/welding/grinding metal repeatedly) and see how real-world packaging works. 
Rear end: De Dion as per W154. Differential fixed to oval section longitudinal chassis rails (cattle yard rails). Half shafts with CV joints. Lateral fixed via mid section of De Dion tube sliding up and down in a housing fixed to the chassis at the rear of the differential (as per W154). Rear springs: longitudinal torsion bars (a Porsche patent apparently) as per W154. Sourcing plan is to obtain some VW Beetle (pre-1964?) front torsion leaves and stack one or two together. 
Front end: Independent double wishbones and coils as per W154. 
Transmission: Comet 40 TAV, gearbox with forward, neutral, and reverse. 
Electric start. 
So - a heap of work to do. 
Much thinking so far, and much more to do. 
I’m looking forward to starting the actual physical build. The running chassis will be easier than the body I feel. I have made complex parts out of fibreglass and carbon fibre previously using various techniques but this will be the biggest I have tried. 
Considered aluminium shaping (English Wheel etc) but I think I’d drive myself mad with both the process and the gear I would end up buying and then needing space for storage. A bridge too far I fear. 
Anyway, that’s it for the moment. Not sure if I have posted this in the correct place - it’s my first venture into public forums. 
I will attempt to post developments, musings, and photos over time. 
Cheers for now. Trust you have a great day and enjoy thinking, making, talking and driving. I just hope I get to that final stage!

Southie