I run mountain marathon year round, but I then soon found out riding bike and running use muscles somewhat differently, not exactly the same set. So I need to add bike training to my already busy training schedule, replace some running time with bike time. I consider that cross-training. Of course, anything to do with mountain, it's not a bad idea to lose couple of ponds of weight.
How about bike?
Bike price can range from several thousands of dollars to just few hundreds. The differences between a 2K bike and 2 hundred bike aren't going to be so dramatic. Shake off few minutes of time maybe; but not the key of pass/fail for climbing mountain. However, most of store available bikes are not tuning for mountains; but rather touring or cross mountain. So if you couldn't find a perfect bike, get a best available one and put some upgrades for your special purpose.1) Change gears. You need lower gear ration. I use a Crankset that has 22 tooth small gear, and a cassette that has 34 tooth big gear, which is not common for a 7 speed cassette. But you can still get that from online. For these set, I have the lowest gear ration of 22/34 = 0.64, which is pretty low already.
2) Brake upgrade. It's better to start a bike already has disc brake, at least for front brake. There aren't much you can do with rim brake. It's pretty affordable to upgrade a brake rotor. Like this 203mm Ravx SL Disc Rotor of mine, I only paid $33, and a adapt bracket to relocate old caliper for couple of bucks. This is already biggest bike brake you can get. Bike brake should match your weight, regular 160mm disc should be good for anyone with middle weight, such as 160lbs. For heavy person like me, I need a little bit more.
Mountain bike riding skill: TBD
