Douglasmotorcycles.net
General => General Douglas Discussion => Topic started by: twirl on 23 Dec 2015 at 14:10
After some testdrives on my MK4 and difficulties with my topgear I found the 3/4 selector fork badly worn out. It's the one on the top of this photo. Maybe the flank to engage the topgear wasn't hardened enough. Everything else would be ok. Today, it's my birthday, I succeeded to get a rather bad looking gearbox (B3574). Gearchange cover is missing, kickstart spindle is broken and it was filled up with dirt and dust. But after dismanteling with much care, I found a useable 3/4 selector fork. On the 1/2 selector fork (on the right) I found some welding. Must have been done by Mr. Douglas, maybe because of a lack of the molding. Can't see anything has ever been broken. Frankly, I would like to repair the 3/4 selector fork, anyone knows how?
You could run a bead of Stellite or bronze along the edge and machine it back to the original profile. Bronze would require less heat and not effect the rest of the part as much. Here in the USA they have a silicon-bronze filler wire called Everdur that works well with tungsten inert gas welding. I have heard that in the UK they have a nickle based filler rod called Colmonoy, that has wear resistant properties and is easy to apply with a oxyacetylene torch.
-Doug
Thank you Doug, I'll try it. That probably will take some time. If I succeed, I will post it.