There are many ways I can attempt to justify Tuesday’s actions. Here are three:
- I needed a hard workout
- I needed a bike to race on Sunday, and was torn between two options.
- Why not?
I took a couple of our demo bikes to Yankee Springs to get a hard workout, figure out which bike I’d ride on Sunday and mess around a little bit. Like a fool, I figured I’d ride each bike on an 11-mile loop of Yankee and compare lap times. Lemme cut to the chase: bonk city on lap two, so let’s not worry about that mess.
The first contestant was an 18″ Kona Big Kahuna, a carbon 29er with a 2×10 mostly-SLX drivetrain, a 100mm Fox fork, tubeless-ready wheels, Maxxis Icon tires and all the trimmings. I’d taken this bike for a spin before, and found it very groovy. Today it felt great. Familiar. Fun. Fast.
Next up was a 17″ Kona Explosif, a steel 650b with a 120mm Rockshox Recon fork, a 2×10 mostly-SLX drivetrain, tubeless-ready wheels, Maxxis Ardent tires and all the trimmings. The Explosif impressed me to no end when I rode it in Washington state, and I was anxious to see if it felt as excellent on my home turf. It did.
- Almost identical drivetrains.
- Similar forks.
- The same wheels but for the size.
- The Explosif is a tad bit smaller, but not by more than 1cm in any meaningful dimension.
- Big Kahuna: 25 lbs. Explosif: 29 lbs.
Before I give my opinions on these guys, it’s worth mentioning that I’m not a great mountain biker. I have friends who can ride rings around me. I have other friends who can ride incredibly complex three-dimensional shapes around me. So there.
The bikes are more similar than different. I put 25 psi in all the tires and found plenty of grip and a decent amount of rear-end compliance. Handling-wise, both of these bikes occupy that nice middle ground between twitchy and lazy. They go where you want. They don’t go before you want them to go, nor do you need to force them to do your bidding; they inspire great confidence. Due no doubt to the smaller gyroscopic force of its wheels, the Explosif was a bit easier to turn, still without feeling the least bit twitchy.
The brakes on both bikes were fantastic. I have nothing to add.
Newer 10-speed mountain bike drivetrains have super-big cog spreads in the rear (11-36!) which dictate really long derailleur cages to support all of the possible ratios. All that chain and a long derailleur cage typically mean a good amount of chain slap going over bumps. Shimano Plus and SRAM Type 2 rear derailleurs have mechanisms to keep the cage tight in place when not shifting, eliminating chain slap. The Explosif has an XT-Plus rear derailleur and it worked great! It was a serene experience to bounce down the trail without the clank clank clank of chain on bike. Very nice.
What about the (ahem) rather significant weight difference? Because I’d put them both on top of the car, I figured the steel bike was a bit heavier, but I was surprised at the difference when I put ’em on the shop scale. Wow. I’ll tell you this: you’d never know it by riding them. Seriously.
What’s left? Ergonomics — extremely similar. Looks — I think they’re both beautiful. The shapes and colors of the Big Kahuna are terrific in an understated, purposeful way. To my eyes, the Explosif looks a little more brutal, more like a tool, something you might find in a machine shop.
What’ll I ride on Sunday? Probably the Explosif. I think, deep in my black little heart, I’m just happier on a 650b. This day was supposed to empirically prove which bike was faster for me, but poor nutrition, sporadic training and an over-ambitious plan laid waste to that goal. Still, what could be better than riding sweet bikes all afternoon, watching Michigan grudgingly accept that fall is here?