you should be okay.
I weld on all manner of motorcycles (stell and aluminum frames) on a nearly daily basis, and have been for two decades.
I always disconnect the negative terminal from the battery. This is especially important if using an arc welder, (stick weld)
Most of mine these days is tig, which the hi frequency style welding doesn't seem to have the risk of damaging expensive little block boxes in modern electrical systems.
I still disconnect though, just to be safe.
'72 BMW R75/5 (Col. Klink),
'02 KTM 400 E/XC,
'05 ktm 125 sx (for sale)
"Hey, are you okay? Can you get up?
I thought you said you could ride"
All the best