Hitchcocks Forum

About a year ago I obtained the flea which was manufactured in 1948, really a RE125. The engine was rebuilt by the previous owner and when dismantled I could see that he had done a good job. The bike started but would soon wet the plug, the spark was feeble. When wired to a battery and coil it ran well and most people who own these bikes seem to settle for this system. I purchased an off the shelf ignition coil, (not Hitchcock), but the spark was no better. The flywheel was remagnetised but this did not help, the crankcase seals were leak free. There is lots of information on the internet about coil rewinding so I thought I would replicate the ignition system on the RE2, primary coil in the flywheel feeding an outside ht coil. On stripping the original coil so as to be able to use the core I think that I might have come across the original problem. I am no expert. The ht coil is in a confined space and much smaller than the ht coil used by Villiers. From my research it seems that for a 6 volt system there should be about 200 turns of about 22 swg copper wire. The Miller ht coil has approx 100 turns which probably explains why it wouldn't power an external coil. Because I did not intend to include secondary windings this gave me enough room to put on the required 200 turns. This now feeds an external coil under the tank. The result is a good spark which works under pressure which the original and replacement didn't. The copper wire cost £3 and about 2 hours work, my lathe was turned by hand so as to make the rows tidy. The replacement coil cost £60 and didn't work, the firm that supplied it were not interested. The easiest solution is to use a battery and it is possible to de earth the lighting coils and use them to charge the battery through a rectifier, the total cost would be about £15.

Well Knock me down with a feather, clevor Trevor......

That is very useful information for anyone with a similar set up.

Well done Trevor. Back when Adam was a lad, one of the projects in my physics class when I was aged 12, was to make an electric motor, out of a few bits of wood, some nails, bare copper wire and a few bits of other wire.
Mine was the best effort in class. (That was a rarity.) However that was back in the days where the physics/science lab had a gas point and a Bunsen burner on each desk with a rack of bottles of dangerous acids and alkalis on each desk as well.

It just goes to show that a lot of those jobs which would seem impossible are indeed quite possible with the correct knowledge.
Isn't the internet wonderful?
It would have been even better, Trevor, to have filmed this and put it up on You Tube.
I'm always thinking that AFTER I've done a job