I will start out saying I am brand new.
I bought a very cheap used train a couple weeks ago (my first one,I feel like I am 8, but I am almost 4 decades older than that). I set it up under the christmas tree with EZ Track. It absolutely flys, even with the small 5.5VA transformer it came with.
I got a Bachmann 4-8-4, SP 4449 for Christmas. Lubed axles as per the hobbie shop we bought it at, railed it (what a chore compared to the little junker), and started running it slowly to "break it in", again according to the hobbie shop. After a couple hours, I sped it up, but even at full throttle, it seemed very slow (about 1/4 speed of little junker).
Went today and bought a bigger transformer, 18VA, and it gets a little more speed, but not much. It takes about 40% throttle to get it started moving, just a crawl, and at 75% it is still moving fairly slow.
Is this normal for these "bigger" locomotives?
Everything depends on your definition of "fast." Some models have a prototypical top speed which might seem slow when compared to other engines.
Since you are new to the hobby there may be some things to check. Are all the rails properly connected to one another? You can loose power that way.
Is there a bind in the locomotive mechanism? Is the engine slowing down on curves?
Since you mention a hobby shop, maybe you should bring it in and let them give you their opinion. This is the best thing to do since, while you are there, you can buy some other goodies for your layout!
As Woody says, top speeds vary. Older locomotive models tended to be gear like they were Bonneville speed title applicants. Newer models tend to be closer to actual top speeds. A GS-4 was a passenger locomotive primarily, so it maxed out at something like 90-100 MPH, but probably ran somewhat slower most of the time.
Merry Third Day of Christmas
Gene
Well, everything seems slow compared to my AHM 0-4-0 that I put a new motor in- it will jump the tracks on a 22" radius curve. If it doesn't jump the tracks, it'll make it around a 4x8 layout in 4.5 seconds. I would consider that to be fast. Slow to me would be the B-mann shay. Average to me would be an Athearn S-12.