Laser vibrational overtone activation has been used to investigate the reaction channel competition in the isomerization of 1-methylcyclopropene (MCPene). The vibrational overtone activation of three types of CH stretches (methyl, methylenic, and olefinic) in the 5 nu(CH) and 6 nu(CH) transitions initiated the isomerization and all three products (2-butyne, 1,3-butadiene, and 1,2-butadiene) were detected by gas chromatography. Stern-Volmer plots were constructed for the appearance of each individual product and the derived experimental specific rate coefficients were compared to those of the Rice-Ramsperger-Kassel-Marcus (RRKM) theory. The rate coefficients for the 6 nu(CH) transitions were in good agreement with the predicted values but those for the 5 nu(CH) transition were as much as a factor of 5 too large. Product ratios of 1,3-butadiene to 2-butyne and 1,2-butadiene to 2-butyne were independent of pressure. In general, these ratios were lower than the RRKM predicted ratios due to collisional deactivation. No evidence of mode specific behavior was observed in these product yield ratios.