Eric called me last week out of the blue and was hysterically excited. His prodigy machinist had been working in total secrecy to bring their finest BBSHD chainring to life. Apparently this new chainring turns the tame stock 46T BBSHD into a different beast entirely. Although I was skeptical, I still got on his website and ordered one for $55 (preorders are available here should be in stock by Monday). When it showed up a few days later I couldn’t wait to install it on my Phat Phuk with a monstrous SunRace 42T granny gear and tear up some snow covered single track.
This chainring went on in about 5 minutes without any of the hassles of trying to figure out how to space it out because of that darn intrusive chainstay. This has a downside, as the chainline is almost 2 cm farther away from the bike than the Lunacycle Eclipse ring or the Lekkie BBSHD Bling Ring. This means that the chainline will be pretty wacked out in the granny gear, but I tested it with a massive 42T granny without any issues.
The 42T granny cog was a total overkill, using only the 36T granny with the 30T Mighty Mini I could climb any incline that I would ever want to climb on a bike. I spent most of my time in the middle of the cassette, which is actually pretty awesome because that is the best place to be when you’re putting lots of power through your wimpy 10 speed drive chain. It felt like the Mini trimmed a few mph off my top speed, although riding in the woods you would never notice. When moving at over 25mph the pedal cadence with an 11T cog was way too fast to even think of trying to keep up with.
The BBSHD is geared from the factory totally wrong in my opinion. The BBSHD was designed with a maximum pedal cadence of over 150RPM. No one except maybe The Flash can pedal that fast and the optimal pedaling cadence for normal humans is much closer to about 60RPM. If I had designed the BBSHD for Bafang, I would have made the maximum motor cadence around 100RPM and geared everything way lower so it would have much more power at the lower RPMs.
With the Mighty Mini you really begin to realize that this motor really comes to life at extremely high RPM cadences that are not achievable with a 46T or even a 42T chainring like the Luna Eclipse or the Lekkie BBSHD Bling Ring.
The trick with mid drive motor design is to match the optimal power output from the motor with the optimal cadence speed of your average cyclist. Right now the optimal power out of the BBSHD I would guess to be somewhere around 100-125RPM. The Mighty Mini lets you gear your bike way down and stay in the optimal motor RPMs to give you the ride of your life (but forget about being able to pedal that fast, not gonna happen).
Is 30T the optimum ring size? I think that 34T would be a better size as you would get some of that lost top speed back and still have plenty of torque. Almost all of my BBS02’s use a 34T Raceface Narrow\Wide chainring on an a BCD104 adapter. I found the Mini to be a much better solution for a small chainring than using a BCD104 adapter and a Raceface chainring is, and it is much cheaper at only $55 as well.
For people who are commuting they may find that the Mighty Mini is a little too small for them. It keeps their pedaling cadences at speeds of over 20mph a little too high for comfort. For hooligans riding single track trails this chain ring is the one to have hands down. It is lighter than anything else and gives your BBSHD massive amounts of power that you simply cannot access with a 42T or larger chain wheel. When you keep the motor down in the 100-150RPM range it’s just pure snow-flinging fun.
With my 5″ actual tired Phat Phuk I find that riding in 5 inches of powder is eerily reminiscent of downhill skiing in the woods, which I did obsessively for over 10 years. The motor is nearly silent and the bike slips this way and that as you roll over the snowdrifts. It feels like everything is right in the world and as you focus down and pick your line through the trees all the stupid, superficial reality falls away and all that is left is … peace.