Based on great experiences with Boyesens on my KDX-200, I got some for my sons KX-60 as part of my effort to make the bike less motocross tuned and more suitable for Enduro.
I put these reeds in at the same time as I put in a Moose Torque Spacer and a bigger rear sprocket, so I can't say for sure which changes had the most impact, but the overall setup made a big difference in making an MX bike a lot more woods friendly. (The torque spacer was a PITA because of the choke knob, but that's a different topic for a different review).
These reeds are cheaper then OEM, and work better, and reeds are a wear item, so I don't see how you could really go wrong with them...
Boyesen reeds are great. They fit great, great quality, and great performance. I feel a lot of the other companys are over rated and that Boyesen should be more recognized, but when you put out products like this you just let the product speak for itself. Great job and I'm sure they will continue satisfying motor heads for years to come!!!
The Boyeson Power Reeds certainly woke up my old RMX. At the same time, however, I added an FMF powercore silencer and had the cylinder re-nikasiled. Overall, these reeds work great, providing extra torque from low to high RPMs.
Bought these to help the bottom end on my sons KX65. They do work as advertised, but it is a subtle change to the power band. My best results included a Moose torque spacer and a Steahly Offroad 10oz flywheel weight. The bike is way easier to ride and much more fun for my son.