According to this: https://www.gamefaqs.com/gamecube/516710-mario-kart-double-dash/faqs/43542

(Scroll down to the real stats, not the star stats)

The Barrel Train's top speed is 57 mph rather than 58 mph and its acceleration is in the bottom third of the pack.

It does have a rear end drift though, does that make snaking easier? If so, why not use the Green Fire which also has it and has a 58 mph speed?

Is it because of the bounciness stat where it is tied for first place with the Piranha Pipes and Boo Pipes?

http://mariokart.video/mkdd-opedia/

All it says is that the Barrel Train is the fastest but it doesn't give an explanation why

Barrel train has good offroad, isn't as bumpy as some as the other karts Lightweights have longer miniturbos, I think it's half a second where middleweights have 1/3rd and heavyweights 1/6th of a second

Thanks for the answer, I didn't know that the mini turbo lengths differed. In that case though, why not the Bullet Blaster with its 58 mph speed and better acceleration?

Is offroad and bounciness really that important? I would have figured that the BB's boost in mph would have more than made up for its lower offroad and bounciness overall.

Yeah at first it was mostly the bounciness that made people use the barrel train, it matters a lot, even with the smallest of bumps You're Mini Turboing most of the time anyway so that 1mph difference vs better offroad and a lot less bumpy is minimal. Besides, acceleration doesn't matter much in (high level) time trials especially since you can drift to get your speed back up.

In fact, the bounciness matters so much that the toad kart is considered the 2nd best kart just because it's really good with dealing with bumps and accelerating fast, being a great kart for bouncy tracks or people starting out (not used anymore tho)

Then on top of that, once a-tech got found out they realized that it works best on barrel train out of like all the karts as well, solidifying it as the best kart

In what tracks does the bounciness come into play?

Every track that has bumps cmon man

What do you specifically though.

Mean

lil bumperinos that make u bounce and get some a i r

I find the barrel kart very useful

I’ve gotten 6m and 17s in mushroom cup with toad & bowser j.r. With that kart. I didn’t take a video of it, but it’s on my records in the games data.

would mushroom bridge or city, flat tracks, or baby park be good for barrel blaster, which has a decent A tech

blaster's a-tech is still kinda bad. The tracks are decent for the blaster as there are no bumps but there's not really a point in using the blaster over the barrel train as there is no clear advantage.