Don't confuse the 50 and 65. They are completely different bikes. The "
EC50 boy" is a "
TXT Boy 50" trials bike with seats and moto tires. Motors are very similar to a KTM mini adventure, but unique to Gas Gas.
The "
MC50" and "
MC65" are Gas Gas/Derbi hybrids.
And for fun, there's the "
EC50 Rookie" or "
SM50 Rookie", whose motors were based on the "
TXT80" trials, but in downsized EC frame.
Clear as mud?