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madison
07-30-2007, 07:14 PM
hey I was wondering if anybody could help me? Im trying to work out the difference between all the cyclocross bike gears some have shimano tiagro and some have shimano 105,what do they all mean? i understand that some a more racy gears where as some are more built for hills, I want a bike that can go really fast and allow me to get up hills ok. At the moment I ride a basic mountain bike (no susp.) and can cycle up any hill without stopping but I would like to go faster on the flat,thanks alot :p

Zen
07-30-2007, 07:25 PM
I ride a basic mountain bike (no susp.) and can cycle up any hill without stopping

Any hill?

Harp Hill?
Putman Road (aka The Wall)?
Nemisis Hill?

any half decent road/cross/hybrid would make you faster on the flats.
as someone said recently, it's not so much the bike but the engine.

SheFly
07-31-2007, 04:46 AM
...some have shimano tiagro and some have shimano 105,what do they all mean?

Those are the levels of componentry that Shimano uses. Tiagro is the lowest level, then 105, Ultegra and Durace. As you move up levels, the componets get a little "better" - lighter, but also more expensive.

Unfortunately, you're going to have to still work to go up the hills, regardless of the componentry ;) .

SheFly

indysteel
07-31-2007, 05:44 AM
I'm going to take a stab at explaining gearing. You likely have three "chain rings" on your mountain bike--a big ring, a middle ring, and a small ring (or granny ring as it's sometimes called). By shifting your front derailleur, you will move your chain from one chain ring to the next. By moving your chain to the big ring, you will be able to access your biggest gears. They will take the most force to pedal. By shifting to the small ring, you will be able to access your smallest gears, which are easier to pedal.

But that's just half the equation.....

You also have a cassette in the rear of your bike. Depending on how your bike is set up, you probably have somewhere between 7-10 different rings or cogs in that cassette. By shifting your rear derailluer, you can essentially "fine tune" your gears. If you shift "up" to a smaller cog, you will be using a bigger, harder to pedal, gear. By shifting "down" to a larger cog, you will be using a smaller, easier to pedal gear.

Obviously, with three rings up front and 7-10 cogs in the rear, you have a variety of combinations that make up your available gears. Depending on the terrrain, the wind, how fast you want to go, how fast you want to pedal (your cadence or rpm), etc., you learn to pick the appropriate gear. The harder the hill, the smaller the gear. For descents, you'll likely want to be in a bigger gear. And on the flats, you'll likely want to pick a gear that allows you to comfortably spin your pedals between 80 and 100 rotations per minute.

When I first started to ride my road bike, I spent most of my time in my middle ring. There were two or three cogs in the back that I liked to use for most flat terrain and if I shifted to the biggest of cogs, I could handle most moderate inclines. It wasn't until I did the Hilly Hundred in Southern Indiana, that I had to become proficient at shifting to my smaller chainring in the front and finding a cog in the back that would allow me to climb really steep hills. I found out the hard way that it pays to shift to the smaller chain ring before actually climbing the hill. It's easier to shift, especially in the front, if the chain isn't under load.

As I've ridden more and gotten faster and stronger, I make more use of my big ring. Even so, there are several big gears that I just don't use much because I just don't have the strength to turn them (yet :)).

There is some overlap in your gears. For instance, you can be in your big chain ring in the front and a big cog in the back and essentially be in the same gear as you would be if your chain was on your middle ring in the front and a smaller cog in the rear. I would add that both chain rings and cogs are described by their number of teeth. For instance, on my road bike my big ring has 50 teeth, the middle ring has 42 and the little one has 30. In the rear, I have 10 cogs that go from 12 to 25 teeth.

I hope that helps.

K-

alpinerabbit
07-31-2007, 06:07 AM
You can adjust your gearing ratio by switching the rear cassette. If you have fairly large rings, and no problem going up the terrains you cycle on - but would like to go faster - switch to an overall smaller cassette.

In terms of grade of your componentry I would eschew the Tiagra and opt for at least a 105-Ultegra combo or pure Ultegra. Dura-Ace is top notch gear and probably too pricey. Not only are you saving weight, you also get quality, smoother shifting etc.

I see here Ultegra cassettes coming from 11-23 to 12-27 and you may be better off with a smaller sample.
I understand you are looking into a complete bike, do you have links?
are you looking into 9x, 10x, ??

Pedal Wench
07-31-2007, 06:53 AM
hey I was wondering if anybody could help me? Im trying to work out the difference between all the cyclocross bike gears some have shimano tiagro and some have shimano 105,what do they all mean? i understand that some a more racy gears where as some are more built for hills, I want a bike that can go really fast and allow me to get up hills ok. At the moment I ride a basic mountain bike (no susp.) and can cycle up any hill without stopping but I would like to go faster on the flat,thanks alot :p

I think you also might be asking about the differences in the components. All the information everyone provided above works for ALL bikes. All of those gears are available in Tiagra and 105. Those are just different names of models. The 105 is a higher-end system, but with the same gears. It's just a little lighter and more durable. Shimano ranges from the low-end (cheaper, heavier) Tiagra to the highest end Dura-Ace (light, and VERY expensive!). It goes Tiagra, 105, Ultegra, and then Dura-Ace, being the very best in the Shimano line.

Hope that helps!

Grog
07-31-2007, 08:19 AM
Sora is actually the lower level in Shimano.

mimitabby
07-31-2007, 08:20 AM
hm. do you suppose Madison is going to come back and read all this good stuff?

indysteel
07-31-2007, 09:23 AM
Sora is actually the lower level in Shimano.

To clarify: Shimano's road line is--from low to high end: Tiagra, Sora, 105, Ultegra, Dura Ace.

Do you wonder whose job it is to come up with these names?

I'm just embarrassed because I thought she was asking about gearing, so I wrote a dissertation on that. In rereading her question, I see that she was expressing confusion about groupsets. Or maybe not. It's not totally clear. :o

Grog
07-31-2007, 10:17 AM
To clarify: Shimano's road line is--from low to high end: Tiagra, Sora, 105, Ultegra, Dura Ace.

Actually according to Shimano's web site it's, from low-end to top-end:

2200
Sora
Tiagra
105
Ultegra
Dura-ace

indysteel
07-31-2007, 10:37 AM
Actually according to Shimano's web site it's, from low-end to top-end:

2200
Sora
Tiagra
105
Ultegra
Dura-ace

Grog. Thank you....I was obviously mistaken. That, and I've never even heard of Shimano 2200!

Grog
07-31-2007, 12:47 PM
Grog. Thank you....I was obviously mistaken. That, and I've never even heard of Shimano 2200!

You probably don't miss much!!

Pedal Wench
07-31-2007, 01:00 PM
Grog. Thank you....I was obviously mistaken. That, and I've never even heard of Shimano 2200!

And I was just afraid of overwhelming Madison. Which I think we still successfully did!

madison
08-01-2007, 03:21 AM
hehe, i guess i sounded abit cocky! i just mean any hill in my area .:p

madison
08-01-2007, 03:35 AM
hey thanks for all the replies greatly appreciated and although I was asking about the different groups of gearing I still really appreciated indanas reply so thank you-it help me understand the different words associated with gearing (derailler e.t.c) which all helps in getting to understand bikes. theres a few bikes Im pretty keen on SPECIALIZED TRICROSS 2008, KONA JAKE THE SNAKE, KONA SURLA and the GENESIS SCOTT I have been looking at all of these and I think I'm probably going to go for the first one, what do you all think?

madison
08-01-2007, 03:39 AM
specialized tricross SPORT that is not COMP as my budget really cant go any further than £700- can't believe im gonna even spend that much-I was only planning on spending £400 when my search first began!

indysteel
08-01-2007, 06:17 AM
And I was just afraid of overwhelming Madison. Which I think we still successfully did!

Probably so. Heck, half the time I manage to overwhelm myself!!!!

madison
08-01-2007, 03:04 PM
don't worry I'm not overwhelmed just grateful for the feedback:D

Somerville
08-08-2007, 06:17 PM
Indysteel ...

Your dissertation on gears 101 was much appreciated by me ... even if it's not what the original post was asking! I can't wrap my head around the relationship between big and small rings, high and low gears, and easy vs. hard to pedal. I know which ones I like to use in which situations, but I am utterly unable to explain it to anyone else! Thanks for the explanation. I think I'll print it out and study it while examining my bike gears.