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Old 09-25-17 | 09:07 AM
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cyccommute
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Originally Posted by Shadowx
I have a Marin Larkspur CS2 hybrid. Im struggling with the gearing cant get comfortable got a little over 500 miles on her. In the high end on the middle ring and cant go low enough on the big ring.

It comes with a 170mm crank arm 48/38/28 shimano chainring 11-32 8 speed sunrace casette . I keep finding myself on the upper end 6-8 in my middle ring and when i jump to the large ring I have to drop down to 4-5 which clicks on the derailer. I can go up hills in 1 and the middle ring.
Your problem is that you are thinking of bicycle gearing like the gear box of a car. It's not a straight linear progression. This calculator will help you see how your gears work. You shouldn't be trying to get into the big/big combination because that gear exists elsewhere. Generally, on a triple, shift off the large ring in the middle of the gearing (the 18 tooth cog in this case) while downshifting and use the middle. If the hill becomes too steep, shift off the middle to the inner before you get to the lowest gear on the cassette as well. In the other direction, shift up when you hit the middle of the range.

Originally Posted by Shadowx
I'm thinking of going to a 2 ring crank. keeping the rear casette in a wider 11-36 (36 since my bottom ring is larger) in a 10 speed casette, and going with a compact 50/34. I'm hoping it will reduce the cross chain since it wont have to travel as far either way and let me use the lower gears in the 50 ring. Does this sound right?

What are you guys using, whats working for you. I'm struggling to decipher the gearings.
MRT2 has a point. Here's what your proposed gearing looks like compared to what you have now.. If you look closely, you'll find that you'll need to use the two rings mostly independently of each other. The transition from the outer ring to the inner ring is large and the difference in cadence to make up that difference is difficult to accomplish. For example, if you are riding along at 90 rpm and 15mph in the 50/24 gear combination and you need to downshift, you have to slow down 5 mph for the gearing to catch up or your have to increase your rpm to 130 to maintain that speed. It feels like you have dropped the chain.

There's also the issue of expense. Swapping from an 8 speed (possibly freewheel) would require new shifters, new cassette, new brake levers and, maybe, new wheel. It's not impossible to do but it would add significantly to the cost of a relatively inexpensive bike. I suspect about $200 in parts and $100 in labor.
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