Originally Posted by Optimumrun

Yeh, I was thinking of the B2 with the nvision 2058 pipe which seems to be an identical pipe as the Werks 2058.
This combo seems the most bang for the buck!

Now if the B2 and the B5 are about the same weight and I got nothing to loose there performance wise, might not be a bad idea to pay an extra 40 bucks for the B5 and have all the power that I will ever need. I could tune down the power to be track specific when I need to via all the other variables such as, clutch springs, clutch shoe material, change the dual rates and expos, etc.
I imagine the 3 extra ports of the B5 doesn't only buy me more power but must has a smoother stable acceleration and a bigger window for holding the perfect tune/ mixture.

Another thing I like about the B5 is the alumimum carb, which is rare, most engines seem to have composite (plastic material)

Than again, of course the B2 would do a little better on the milage I presume?
Giving me what?, 10 to 12min on a 125cc running on a average size short course?