Thre are several ways to interpret that question. If you're asking about things that are actually called levers, then the answer is probably 4 - one pair of shift levers and one pair of brake levers. Unless it's a gripshift equipped bike, in which case it'll only be one pair of brake levers.
Or maybe it's a single-speed, in which case it also only has brake levers.
Or maybe it's a fixie, which don't use shifters or brakes.
Or its using rear gears only, giving it 3 levers. One shifter, two brakes. Or it's a rear gear gripshift - two brake levers.
Or maybe you're asking about the mechanical definition of levers, in which case there's be a lot more. The handlebar is a lever, each crank is a lever, the wheels may be seen as levers. If you've got quick-release wheels and seatpost, those are levers too.
There are too many good mountain bikes to mention.
Online, mountain bike parts can be bought from many online suppliers. Jenson USA and Go-ride are two examples of sites that dedicate their inventory to mountain bike parts.
There are many magazines that are relevant to mountain bikes. Some of them are Bicycling Magazine, Bike Magazine and Cycling Magazine.
Pacific Northwest. Tons of epic mountain bike trails, also California has many great trails.
Depending on the mountain bike that you have will depict the amount of gears. Most bikes for adults typically have about 21 gears. If this does no answer your question then what are levels?
IMB is a great Mountain Biking Magazine. It shares many stories about biking which includes stories from around the world. The stories are about races and show experiences that may interest you.
Yes there are many if you just google "Bike parks" and "Cornwall" as one search
Many tour operators arrange mountain bike holidays. Some of these tour operators are Skedaddle, Pure Mountains, MudTrek, Sierra Cycling and Mountainbike Tours.
There are many different brands of mountain bike gloves available for purchase. Some of the most popular brands for these gloves are North Face, Fox, Six Six One, Giro, and Dakine.
Many sites like autobrakes.com offer many educational tips and guides about repair. You will have to do some looking though.
Expedition Everest Primeval Whirl Space Mountain Big Thunder Mountain Rock n Rollercoaster Test Track?
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