Thanks to everyone who responded so far! I love all the opinions and speculation! Based on the way the answers are going, I have some insight because I'm a lawyer, and I have actually done some defense work for amusement parks- not Disney related. Generally, the insurance companies only require that you go in accordance with manufacturer's recommendations and ATSM Amusement Ride Safety Standards, which are utilized throughout the industry. I haven't seen an insurer actually impose a height requirement on their own. My 1st thought was some strange California law too, but unless it has changed, California law only provides:
"The operational limits of the ride and the specifications used to evaluate testing results shall be established by the owner or operator using all manufacturer-originated information that is reasonably available and relevant as well as whatever additional information is necessary to ensure that the operation of the ride is within the design limitations of the ride."
This would mean that it would be Disney in accordance with the manufacturer which would determine the height requirements. If the ride base is the same, generally you would think you would see the same height requirements at both parks.
That means for some reason, Disney has selected the different height requirements. I think Doconeill may be onto something. If KRR has pull down bars, and GRR does not, that may be the explanation for the difference in height requirement on that one. Does anyone know whether GRR has the pull down bars? If not, I bet we have the answer to that one! If they do, maybe Princess Sleepy is right that there may be a different angle or speed that comes into play?
I thought I read the ride vehicles and tracks themselves were the same for Dinosaur and Indiana Jones, but I could be wrong about that. Anyone know if there is a difference? I still have no clue why there is such a difference in height requirement on that one.
Space Mountain, I am almost positive the difference in height requirement is due to the ride cars themselves. That is just my guess, but I would bet money on it. DL has completely different ride vehicles than WDW. Two riders sit side side by side in the DL cars so you can sit beside your child, where at WDW, they are single file, so you would be in front or back of your child. Because the ride car structure is completely different, that could easily lead to different manufacturer height requirements.
