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RV Adventure: Replace a Mountain Bike
Part 3
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What makes these bikes go and what has made mountain biking the most popular cycling sport over the last 25 years is the gearing. Old Blue has seven cogs in the rear with three in the front giving (in theory) 21 speeds. The Trek has nine cogs with three chainrings so 27 speeds. Much of this is sales talk because several of those speeds on both bikes are identical gearing depending upon which chainring and which cog is chosen. There is a proper way to shift gears. As a bike shop owner, I used to give |
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mountain biking lessons for the North Lake Tahoe Parks and Recreation department. The lesson was four hours long and much of that time was used to discuss how and when to shift from one speed to another. Both these bikes use the top-of-the-line Shimano Deore XT rear derailleurs and even though there is 18 years difference in age, I can't tell the difference in the shift.
Note the size of the largest cog. The Trek has a larger rear cog. This is going to give a lower gear range and in theory, an easier ride up hill. The problem is a lower gear means the bike is moving forward at a slower |
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speed. The slower the speed, the harder it is to stay up-right especially if you are being tossed from side to side by rocks or uneven terrain. I do like the lower gear however.
The front set of rings are called "chainrings". Both bikes have three but the quality of the chainrings on Old Blue are superior to the |
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Trek. I noticed that the $2,200 Trek (the bike above my bike) still used the same chainrings so I guess you have to spend $3,000 to get the really good chainrings. Again note the size of the rings. A larger chainring means you can continue to peddle going down a steep hill, a smaller ring means you will have yet a lower gear for climbing. |
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The Trek on the left has a presta valve while Old Blue has a schrader valve. The presta valve is a bit more "high-tech", lighter weight more reliable but can't be filled at a gas station pump. I've always favored the presta valve but 18 years ago, they were only available on road bikes. It's not a big deal but I'm glad to have the new valves. |
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Finally, you may have noticed in the photos that I have some strange looking pedals on both bikes. These are "Frog" brand pedals where a cleat on the bottom of the shoe locks to the pedal. The foot is released from the pedal by swinging your heel away from the bike and pulling up at the same time. I've been using |
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these pedals for 18 years so I'm almost use to them now... a long learning curve. Cleated pedals give you about 10-20% more power and are especially nice when road biking. They also make sure your foot is in the perfect position for the most power and control. This is another one of those things you would not want to do if only |
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riding casually. As I mentioned before, I've been pretty serious into cycling as a sport since 6th grade so I don't consider myself a "casual" rider. I'll tell you more in the pages about road riding which I haven't had the time to complete yet. Finally, if all you need is a bicycle to ride a mile to the grocery store once a month, then nearly any bike will do. But if you want to ride for exercise and or endurance/stamina, I highly recommend buying a bike from a reputable dealer who will fit you properly to the different sizes of frames (the wheel size does not change) that are available. |
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Return to Part 2 |
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