6 speed kids bike derailleur

[danr2013]

I have a cheap kids bike with 20" wheel, a 6 speed right thumb shifter, single front chain ring. The derailleur needs to be replaced. I have an 18 speed parts bike that I plan to take the derailleur from. will that work?

Dan...

[DaveM]

Probably. If it mounts to the frame in the same way (integrated hanger vs. frame mounted hanger) and is of similar cage length, you shouldn't have a problem. If the 20" has index shifting and the two shifters are different brands, it might mess up the indexing.