12/25??? 12/23??? 11/30???

[fatboysoontobeslim]

looking at possibly upgrading cassette on my giant defy 2 could someone please explain wh at these figures are when looking at cassettes and how do i know what mine is on bike already. excuse my thickness

 

[martint235]

looking at possibly upgrading cassette on my giant defy 2 could someone please explain wh at these figures are when looking at cassettes and how do i know what mine is on bike already. excuse my thickness

Simply put they are the numbers of teeth on the smallest and largest cog respectively. Use the number of teeth on the cassette with the number of teeth on the front chainring to come up with a gear ratio. (use Sheldon Brown here). The higher the ratio, the faster you'll be able to go before you spin out. The lower the ratio the easier it will be to climb hills. I have a Giant SCRA1 with 53/39 at the front and 25/11 at the back (and I struggled on the recent Hilly 50!!!)


Before anyone jumps on me, I did say "Simply put"

 

[GrasB]

It's simple the number is the tooth count of the smallest sprocket/largest sprocket. To work out what you have at the moment count the teeth.

A word of warning, when you start looking at things like a 11/32 cassette the intermediate gears may not be the same. SRAM tend to try & keep a tight bunch of gears at the small end of the cassette & then have bigger jumps at the larger end, while Shimano tend to have more even spacing between the gears.

 

[Fozz]

are they cricket scores???

 

[fatboysoontobeslim]

could be fozz

doing well if they are he he, ok then should i stick with the same size as on the bike already i f im upgrading???

 

[mr Mag00]

extensive use of ? i like

 

[GrasB]

could be fozz

doing well if they are he he, ok then should i stick with the same size as on the bike already i f im upgrading???

The safe bet it stick to what you have because you know it but which cassette to change to is one big can of worms to open:
Do you use all your gears?
Do you find you want lower gears?
Do you find that there are holes in the gears you have now?

 

[fatboysoontobeslim]

i sometimes find i want a lower gear when the chain is on the big cog on the front if that makes sense. to be totally honest im probably not using my gears right anyway, i really need to go out with a more experienced rider who can put the use of them in laymans terms if that makes sense

 

[GrasB]

You need to worry when you're on the bottom chaining (the smallest 'cog' on the front) & want to have more gears in the down direction, aka omg my legs are about to die & really NEED to change down...

Really you should only use the largest 2 sprockets on the back if you're only going to be on them for a short period else drop to the middle/bottom chainring.

 

[fatboysoontobeslim]

with regards to which cassette ill probably stay with shimano as thats whats on it and may upgrade it to a 105 or ultegra, i take it upgrading will benefit me in the sense it will go through gears better or last longer maybe, as i said im a novice when it comes to cycling so bare with me and thanks for the help

 

[2Loose]

If it is a 2010 model, you can't (easily) go for a cassette with more than 27 teeth (lowest gear\Biggest cog).
It will have a 12t to 25t range as standard already...

But as GrasB says, if you want a lower gear range and you are using the big cog at the front at the time, then change to the smaller front cog.

 

[HLaB]

If it is a 2010 model, you can't (easily) go for a cassette with more than 27 teeth (lowest gear\Biggest cog).
It will have a 12t to 25t range as standard already...

But as GrasB says, if you want a lower gear range and you are using the big cog at the front at the time, then change to the smaller front cog.

I thought that too but Shimano are selling 12-28 105 cassettes

 

[GrasB]

I tend to find Shimano 105 is the sweet spot for price & performance on most things, I also feel it outlasts Ultegra & DA.

 

[jugglingphil]

.........., i really need to go out with a more experienced rider who can put the use of them in laymans terms if that makes sense

Where are you based? You may live/ride close to someone on this forum who'd be willing to help.

Otherwise the question is, why do you want to upgrade your cassette?
Hard going up hills? To many gaps (i.e not smooth changes between gears)? Spin out going downhill? Worn out? etc etc

 

[rockyraccoon]

I agree with jugglingphil. What are the reason for upgrading? What do you need? First try to learn how to use them and improve the shifts. If the ones you have now are not ideal for what you need then you upgrade.105+ are better as long as you know how to use. Otherwise if you are not changing gears correctly you will not notice any difference with the upgrade.