W/NG - Horn Repair

 Well it's been a week of cracking through little bike jobs, alongside welding up rust holes in the fuel tank of yet another Eastern Bloc two-stroke, this time an MZ TS125 - but more of that later.

For some while the W/NG horn has been a little touchy, because the horn adjuster doesn't work very well due to a stripped brass lock nut, though I improved it a lot in the middle of last summer by squashing the nut slightly. It has an odd thread, 0.209" x 36 tpi which I found by luck on eBay - it's a bicycle tyre valve core thread!

The adjuster lives behind the tone ring nut:

The one that was fitted had a 10 mm hexagon and was a half nut - it may have been 0 BA at one time and forced on, but I suspect it was the original as it was cadmium plated, or perhaps faded nickel over brass. I made a new one out of 0.445" EN1 hexagon bar, turned with a significant chamfer on one side to clear the inside of the domed tone ring nut:

It works beautifully.

That's it for a bit on W/NG repairs. I still have the bum pad to make and the dynamo bearing felt to put in, and I have to monitor the new seal in the decompressor. The jury is still out on the field stand springs - they still have a safety chain on, though it hasn't made another bid for freedom since I tightened and retempered the bottom spring.