I have been looking around gen 1 a lot for chansy but yet I never seem to find one. Can someone tell me where they spawn and thier spawn rate and the time between spawn?
They are classed as a rare spawn and so will only spawn on the odd occasion! You can find them in spawn area and on the path to fortree. You can also check #rare-spawns on discord as it can be easier to find one from there.
#113 Chansey Wild: Extremely rare (0.297% with 2h between spawn times) in normal biomes, trainer level 14 required. Evolutions: X Purchasable: Can be found in Rare Eggs. This is from this thread doc: http://forums.pokefind.co/index.php?threads/how-to-get-every-single-pokémon.359/ That thread also contain a map showing normal biomes areas.