Better climbing cassette

[Kies]

I was cleaning the bike after Fnrttc and have noticed my top 5 gears are looking like shark teeth. With 2500 recorded miles on the clock, it's time i look at a new chain and cassette.
Transmission:


Cranks Model:
Shimano R565 50/34, 172.5mm cranks

Cassette:
Shimano Tiagra 11-28

I know nothing of gear ratios but i'm aware how hard i find climbing hills. Looking at the wear on my cassette it's obvious i use the top 5/6 gears a lot more. Would a change in cassette help me?

 

[Peteaud]

I use a 30T and although some say there isnt much difference, there is to me.

 

[Mr Haematocrit]

i use 50/34 compact with 11/28 on my tarmac which seems to be a great compromise a change in cassette may help you climb better but you have to be aware of rear mech clearance.

 

[Milzy]

Different Opinions, it depends on your strength. I can grimace up 30 % climbs on a 28. I'm fine around most of the uk with a 28 but if I went overseas to the Pyrenees for example I'd most certainly want a 30 or 32.

 

[Kies]

@Peteaud - will investigate this cassette a little more . So much to learn before i make a decision

 

[BimblingBee]

If you've done 2.5k miles and know that you are still finding it hard then a new cassette is a reasonable decision. Small changes can have a big impact so going to a 30t one may be just enough. Obviously you need a new chain and it's likely you may need a new rear mech but I'd leave that until you've tried it out. Shimano mechs are often capable of more than they advertise!

 

[Peteaud]

If you've done 2.5k miles and know that you are still finding it hard then a new cassette is a reasonable decision. Small changes can have a big impact so going to a 30t one may be just enough. Obviously you need a new chain and it's likely you may need a new rear mech but I'd leave that until you've tried it out. Shimano mechs are often capable of more than they advertise!

Tiagra should take 30T as many 10sp are now 12-30 standard.

I run a 30T on my 9 speed Tiagra without issue.

 

[slowmotion]

Personally, I would go for some seriously easy gears on your cassette and chainrings. Nobody will force you to use them but they will still be there when you really need them.

 

[Mo1959]

@Kies That's the same set up as my bike and I would check with your local bike shop as I know mine has what is called a short cage derailleur and, I could be wrong here, but I think 28 is the max it will take without further modification to a longer cage as well.

I agree that the 28 is fine for 95% of the time but I have stumbled on the odd really steep bit when I could do with an extra couple of gears too.

Be interested to hear how you get on with this since I'm not getting any younger and may have to look at doing the same in the future.

 

[Peteaud]

@Kies That's the same set up as my bike and I would check with your local bike shop as I know mine has what is called a short cage derailleur and, I could be wrong here, but I think 28 is the max it will take without further modification to a longer cage as well.

I agree that the 28 is fine for 95% of the time but I have stumbled on the odd really steep bit when I could do with an extra couple of gears too.

Be interested to hear how you get on with this since I'm not getting any younger and may have to look at doing the same in the future.

28T is not the max, its what Shimano say is the max.

Look at the 10 speed Felt Z5, that has a 32T cassette.

It depends on the hanger length, bike frame etc.

Ive even had my 9 speed Tiagra with a 32T on and although right on the limit, worked fine.

 

[Kies]

Sorry guys I should have given you my full transmission spec. Giant Defy 1 - 2012

Transmission:


Cranks Model:
Shimano R565 50/34, 172.5mm cranks
Bottom Bracket Model:
Shimano, press-fit
Rear Derailleur Model:
Shimano 105, short cage
Front Derailleur Model:
Shimano 105 braze-on
Shifters Model:
Shimano 105 STI
Cassette:
Shimano Tiagra 11-28 (10 speed)

So mainly 105 which is why I will be looking for a 105 cassette. From what you learned chaps have said so far a 12-30 cassette would give me a slightly better ratio for hills without affecting my top flat speeds. Given the wear is on the 5 biggest cogs. Petaud is running similar without issues so a visit to the lbs to confirm.

 

[Andrew_P]

I would say you would get away with it, the main issue might be chain length if you cycled 11t back & 34t front the rear derailleur might run out of spring loading to hold chain tension.

28 to 30 won't make a huge difference, SRAM do a 12-32t

 

[PaulSecteur]

Shimano updated their rear derailiers a while back. The 5700 had a max size of 28 teeth, the newer 5701 would accept 30 teeth with a triple, or 32 with a double.

You can tell which one you have by looking at the back plate of the parallel link. It will be marked RD-5700 or RD-5701.

 

[I like Skol]

IMO I think tinkering with a couple of teeth on the cassette will make marginal difference to your hill climbing experience. If hills are such a problem then I suggest a total drivetrain rethink and switch to a triple chainset. Some may scoff and ridicule this suggestion but it can give you an enormously flexible gearset that will see you climb anything you may contemplate.

This will be a much more costly exercise than a simple cassette swap (shifter, chainset, front & rear mech + chain and cassette) but will give you the bike you need. On second thoughts, it might be simpler/cheaper to swap bikes.

 

[Kies]

IMO I think tinkering with a couple of teeth on the cassette will make marginal difference to your hill climbing experience. If hills are such a problem then I suggest a total drivetrain rethink and switch to a triple chainset. Some may scoff and ridicule this suggestion but it can give you an enormously flexible gearset that will see you climb anything you may contemplate.

This will be a much more costly exercise than a simple cassette swap (shifter, chainset, front & rear mech + chain and cassette) but will give you the bike you need. On second thoughts, it might be simpler/cheaper to swap bikes.

I am an average climber,hills don't fill me with dread. I'm the sort that picks my lowest gear and spins (slowly) until i reach the top. It was an idea to change the ratios slightly as my cassette and chain will need changing in the near future. I have a triple on my T3 and Sirrus. Next time i attempt Ditchling maybe :-)