We have measured the bending modulus of several different CVD (chemical vapor deposition) grown MWNTs using a vibrating reed technique. The MWNTs are produced from a thermal decomposition of three different precursors: (i) xylene/ferrocene, (ii) xylene/ferrocene/melamine (nitrogen-doped), and (iii) trimethylamine (TMA)/ferrocene. The first two precursors are used to compare the mechanical properties of typical CVD-grown to bamboo-type MWNTs. Nanotubes prepared using the third precursor shows relatively fewer walls (∼ 4–20 compared to ∼15–40)) and defects compared to those prepared from the xylene/ferrocene mixture. The resonant frequencies of these nanotubes were measured optically in air using a dark field light microscope. The diameters of these nanotubes range from 50 – 160 nm as determined from TEM and the average length is ∼ 10 microns. For the xylene/ferrocene and trimethylamine/ferrocene tubes, the average bending modulus is estimated to be 0.1 and 0.3 TPa, respectively. However, the bending modulus for the nitrogen-doped tubes is ∼9 GPa which is significantly lower compared to regular MWNTs implying that the bending modulus decreases with an increase in wall defects. These findings are in reasonable agreement with those reported previously by Wang et al.