The bikes may have hidden stats, but if they do they're not showing up on the DestinyTracker database entries, even though they Do show hidden stats on guns. One of the primary handling differences I've noticed is between the perks Quick Brake (QB) and Destabilizers (DS). Old bikes with QB (basically all of them) handle poorly for me (whether I use the brake or not), while old ones with DS, like Lysander's Cry, handle better. All the new-style race bikes have DS and handle best for me. So, I'm not saying that use of the perk makes them handle differently, though it certainly does that, I'm just saying it feels like the perks have some kind of unseen, passive effect on handling. I spent a good few races last night swapping between Lysander's Cry and SnowScream. Lysander handles better than SnowScream (for me) so the difference between DS and QB does seem to affect handling. I ran a few others too, just for comparison, like the Vector Infinite and even the basic S10. All the old-style sparrows, in both QB and DS variants, seemed to either take corners very tight or get thrown way, way wide. Vector Infinite does drag-race a little better due to it's slightly higher boost stat, and I assume the SR-1 Swiftriver would as well, but I don't have it to test. I then switched to a race-type, Aeon Glow, and noticed a marked improvement in handling. The newer-style also seems to be more forgiving in the turns, if somewhat slower on the straights. The newer ones also seem to respond better to throttle-feathering. Most times I tried to feather on an old-type my boost would die completely, forcing me to let off the trigger momentarily before hitting it again to re-engage. Never has happened on a race-type. So, with a sample-set of one, it seems to me that the old style sparrows, with QB, handle the worst, the few old style with DS (Swiftriver, Tumbler, Lysander) handle better, and then all the new-style sparrows with DS handle the best. But that's just my experience.