Pushbike speedo drive conversion

[Agent Buchwald]

I've tried the search without a great deal of success - I'm going to attempt to put a pushbike speedo on the cutdown using the speedo drive so it's neat - is it just a matter of drilling out the speedo drive and fiting the reed switch with a magnet araldited to the worm gear, any advice welcomed on which unit to use, I've got a cateye on my pushbike that looks like it might work, thin reed switch and custom wheel size but any help appreciated.

[camel]

i use one from a bracket on my rear shock with the magnet glued to my rear wheel rim,i use a cheap sigma for a pushbike

[Agent Buchwald]

That could be a better way of doing it - thanks