Any idea what sort of steel alloy a modern frame is made of - should I just use ER702-2, or something more versatile like 309L? I asked KTM, they just told me not to weld their frames under any circumstances!
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And given the large amount of electronics on a modern bike, is disconnecting the battery enough? Disconnecting everything electronic would be a big task! And does earthing close to your weld help to prevent damage?
Sorry, a lot of questions!