Originally Posted by mrdoright0405
I meant they have "Shimino" and "Sram" parts. Kevlar tires, etc.
Shimano and SRAM make components at all levels. Just because the label says Shimano doesn't mean it's the same quality across the board. As an example, let's take a look at the Mongoose XR200. Its specs says it has a Shimano TX50 rear derailleur. Let's compare that to say a midrange full-suspension bike like the Specialized FSR XC that sports a Shimano M510 Deore rear derailleur. So what does this prove? Well, Shimano's parts designation belays its intended use. The RD-TX50 is part of the Tourney group that's intended for casual street and comfort bikes. The M in the RD-M510 denotes an actual MTB component intended for offroad usage. The MTB components are built to much higher standards and are much more durable than the Tourney components which may not have sealed bearings and use cheap plastic parts instead of metal.