cassettes

catchingup

hi all, im new to the forum after just been looking in for a while and looking for some of advice.
Ive found this forum a great help in the 18months or so ive been cycling.
Ive bought a new set of wheels and was looking at buying a new cassette to fit on these so i can just change
wheels and use both.
At the moment i have 10 speed tiagra with a 12-30 cassette and was going to buy a new shimano 105 5700 cassette 11-28 for my new wheels.
Will this work and would i be able to change wheels without doing anything to chain?
I go up a lot of hills were i live and just get up them with current gears so will i notice the differance between the 2
as im looking to use new wheels for weekends and the old ones for commute?
thanks for your help
mark

smidsy

Chain length should be fine. Tiagra/105/Ultegra etc. does not matter - all will fit.

catchingup

thanks very much smidsy

catchingup

just reading up on fitting it myself when it arrives and there is talk of a spacer?
can anyone help me with this.
will i need to buy 1 or will it come with cassette?
thanks

dmclite-3.0

If you already have a 10 speed cassette fitted to the bike there will be a 1mm spacer on your hub behind the cassette you have now, just use this.

northpole

I didn't know you could get a 30 tooth cassette for a road bike! Dropping down to a 28 tooth max cassette will mean that the most difficult hills will require a bit more effort from you. I'm not sure what the second largest cog would be on your 12-30 cassette but I suspect that the 28 ring will be not dissimilar to the second largest ring on your existing one. Hopefully that will give you an idea.

The 11 tooth smallest ring will give you a bit more drive going downhill or on the flat with a tailwind!

The difference between old and new will be partly dictated by whether you have a standard chainset or a compact.

Peter

mroli

Sram/Shimano chains and cassettes are also interchangeable.

wishitwasallflat

catchingup wrote:

At the moment i have 10 speed tiagra with a 12-30 cassette and was going to buy a new shimano 105 5700 cassette 11-28 --- I go up a lot of hills were i live and just get up them with current gears so will i notice the differance between the 2

If you can

just get up

your hills with a maximum rear cog of 30t why on earth do you want to swap to a maximum of 28t? It will be harder and you will notice the difference. As someone else suggested if the second largest cog on your 12-30 was a 28 and you never use the 30t this makes sense - if not it doesn't (unless you want to force yourself to have no option but to wokr harder on those hills but

just get up

doesn't seem to indicate that plan).

arlowood

I moved in the opposite direction earlier this year when I was struggling on some sportives with the short steep hills. Swapped my Ultegra 11-28 for a Tiagra 12-30.

The change was an immediate benefit and, although I now rarely if ever use the 30 cog, it is a comfort to know that it is there if needed.

One advantage of the switch is that the gear ratios are indentical over 95% of the cassettes. So effectively with the Tiagra cassette you loose the 11 tooth cog and have the two low end cogs as 27 and 30. Otherwise all the cogs are the same so you will not be struggling with cadence issues if you swap from one to the other.

Contrary to earlier comments, the Tiagra 12-30 cassette does not require a spacer so the OP should make sure a spacer is supplied with his new 11-28 if he goes ahead with purchasing one.

However, as others have said, it is probably a step in the wrong direction to drop to a max 28 cog if he is already struggling on hills with 27 and 30 cogs as his low gear options.

catchingup

Reading the replys would seem i,d be best to go for the same cassette as i have then.
Plus i wont need the 1mm spacer.
Thanks for the reply,s been a great help.