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       #Post#: 14807--------------------------------------------------
       1924 Supercharged Sunbeam
   DIR By: Mark L
       Date: April 15, 2026, 1:52 pm
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       Hello, I should introduce myself properly as I signed up for the
       forum almost a year ago and didn't at the time. I live near
       Reading and have been thinking about building a cyclekart for
       about 8 years, ever since I built my children a Stevenson
       Projects Bugatti pedal car (see first image). I thoroughly
       enjoyed making the pedal car, learnt a great deal and the kids
       have loved playing with it.
       It was when looking at the plans for the pedal car that I
       clicked on the links for the cyclekarts and thougt to myself
       that I'd love to build a powered version of the pedal car one
       day. My wife gave me a copy of "Grand Prix and Sports Cars" by
       Rex Hunt for Christmas which is a fantastic collection of scaled
       drawings of racing cars from 1894 to 1964, and from here I was
       drawn to the 1924 Sunbeam as an inspiration car - specifically
       the "Cub" version in the attached photos.
       So I ordered the steel for the chassis last year, taught myself
       the basics of Mig welding and set to work putting the chassis
       together - I've learnt a great deal and made a ton of mistakes
       (like the time I made a wooden plug to hold the sides of the
       tubing apart having cut the top off for the profile of the
       front, then welded the top piece on over said plug and realised
       that I couldn't get it out...cue lots of drilling out with the
       largest auger bit I could find).
       I've been taking my time, watching lots of youtube videos (if
       "Old Guy Does Stuff" is a member here, thank you!) and have got
       to the stage where I have a Hyundai 212 electric start engine
       and Comet TAV mounted to the chassis, a rear axle with brake and
       drive disk, painted wheels, a 420 chain and a mounted front
       axle. Next steps are to: Build a floor, fix the steering, work
       out how to mount the old motorbike brake caliper and master
       cylinder, fit brake and throttle pedals and plan out the body
       work which I'm intending to make out of aluminium as I'm really
       enjoing learning the metal work side of things - would recommend
       "Professional Sheet Metal Fabrication" by Ed Barr as a really
       good place to start for a total novice.
       I'm also enjoying learning about the engine, and the
       modifications that can be made...given the profile of the tail
       of the inspiration car I'd like to make the engine profile as
       low as possible so I'll mount the fuel tank elsewhere and
       replace the stock exhaust box with a new one and the stock carb
       with a Mikuni - I've also had the engine open and removed the
       oil sensor and the governor (removed the flywheel and simply
       knocked it out from the back)...which leads me a question I've
       been puzzling over.
       I would like to keep the electric start if possible as the
       thought of having a big red "push to start" button appeals to my
       inner child...but that requires a flywheel with a ring gear.  If
       the governor is removed and the valve springs uprated,
       everything that I have read so far has recommended replacing the
       original conrod with an aluminium one, and the original flywheel
       with an aluminium one. However the only aluminium flywheels with
       ring gears I can find are billet aluminium jobs from America
       that are a) expensive and b) against the rules. I think it would
       be possibe to remove the ring gear from my standard flywheel,
       machine a cast aluminium flywheel to allow an interference fit
       and get things to work that way...but would that be allowed
       under the builders rules which mention no machined flywheels? I
       would love to know what others with electic start engines have
       done, even it is simply "used the original and took our
       chances".
       Thanks for reading, and I'll be updating this as the build
       progresses (albeit probably quite slowly).
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