Gear Ratios?

furiousox

Hi all.
I'm currently running an Ultegra 6600 groupset with a 52.39 chainring and a 12.23 cassette.
I find that I struggle on some steep ascents and tend to use more caution than speed when I'm descending.
For that reason I'm thinking of changing the cassette to an 11.28.
Just wondering if the 11.28 would work out ok with the 52.39 or would it mess everything up?
Thanks!:)

niceonetom

An 11-28 will work with a short cage 6600 r/d (though I think it's technically beyond its design specs). Shifting will be slow and feel imprecise though compared to running an 11-23.

I've used 11-28 in the Alps where the consequences of being over-geared are serious but I'd avoid using one here. Why? Because of the gaps - they're bloody massive at the thick end of the cassette and the each shift requires a big jump/drop in cadence to maintain momentum. I found that hugely irritating.

You don't sound like you reed the 11 so maybe consider going to 12-27 instead. The gaps are still big but not as extreme and you get nearly all the benefit.

Alternatively change to a compact. That's what I use with an 11-23 and find that it works very well. I still have a decent ultimate climbing gear and 50/11 is enough for all but the fastest descents. The only downside to that set up is, of course, the big jump when changing chainrings, but comparing how often I shift at the rear to how often I shift the front I think it makes sense to sacrifice front shifting in order to run a tighter block.

cdaly_

Should be fine but I wouldn't bother with the 11. I went from a 11-28t to a 13-28t because I didn't like the gaps between gears. I suspect you'll find a similar issue. Mind you, I did make that 13-28t up myself by taking the 24t and 28t from my old 11-28t and putting them on a new 13-25t. Easy enough task, just punch out the three retaining pins from the cassette and it all comes apart. Don't put the pins back in though or there's a risk they could migrate into your spokes...

Zorba

Yes i'd go with a compact 50/34 and it's up to u but i've then got a 12/25 on the back which is all i need, well would've liked a 27 on the back for the Sean Kelly.

If u do go with the compact as niceonetom said the gaps between the gears won't be anywhere near as big, nothing worse than one gear is too low and the next one is too high.

furiousox

Thanks for the advice so far guys.
So, to gain a couple more low gears for climbing, with no clunky gaps between shifting, a 12-27 would be the best option?
(Without changing the 52-39)

Rowery

Furiousox, I'm afraid I can't offer a lot of help but I would like to ask another related question on this, before I do, I will say, I changed the cassette recently going for lower gears and now find that on fast decents I have to spin like a madman to get anything from it in a 52 chainring, of course much nicer cadence in 39 on the ascents.

My question - would people race on a compact ? or would people change cassettes around on a double to suit what they are up to.

furiousox

What cassette did you change from/to?

niceonetom

I've raced with 50/34 - 11/23 this year without issue. 50x11 is a bigger gear than 53x12 which was as much as anyone used (pros included) for a long time. If you're on a descent and you're "spinning like a madman" in your last gear you'd probably go faster if you stop pedalling and do your best impersonation of a bullet - elbows in, chin to stem, arse on the tip on the saddle.

You should be able to spin well up to 120 or 130 rpm, which'll bring you into the 70+kph area. How fast are trying to go?

Where are these races in Ireland where you really need 53x11?

paddymacsporran

I agree Tom, I've raced on a compact too this year, never had a problem with spinning out.

It's covering the gaps that bothers me!!!

ashleey

Try a 12/25 on the back. I swapped out an 11/23 after realising I never used 11 with my 52/39 tiagra. I did the skyride with the 12/25 and it was fine and is cheaper and simpler than swapping to a compact. Better then to buy a new bike with a compact and wave goodbye to your credit rating.

furiousox

Ideally I'll replace with an ultegra cassette but I assume a 105 cassette would be compatible too?

paddymacsporran

Yes, no problem.

n-dawg

I had very similar issues last year. I used to have a 53-39 crank set and 11-23 cassette. I swapped for a compact and haven't looked back. It give a good few extra gears the same as swapping the cassette for a 12-27. but without any of the gaps.

I picked up the crank set from ebay for €125. A cassette would cost about €50 so its a bit dearer but really worth it.

Rowery

furiousox wrote: »

What cassette did you change from/to?

I went from a 9 speed 12-23 to a 14-25, this was a combination of lack of knowledge and impatience. Just wanted a cassete for some wheels I had just got.

Rowery

niceonetom wrote: »

I've raced with 50/34 - 11/23 this year without issue. 50x11 is a bigger gear than 53x12 which was as much as anyone used (pros included) for a long time. If you're on a descent and you're "spinning like a madman" in your last gear you'd probably go faster if you stop pedalling and do your best impersonation of a bullet - elbows in, chin to stem, arse on the tip on the saddle.

You should be able to spin well up to 120 or 130 rpm, which'll bring you into the 70+kph area. How fast are trying to go?

Where are these races in Ireland where you really need 53x11?

This is great news, I haven't raced yet but was worried I was going to be needing a double for some reason, I love the compact I have.

70Kph would be a new record for me, and probably not one I would like to be at for too long.

Now I can go about project upgrade winter bike from a tripple to a compact, some might say a waste of cash but I disagree, I think its vital I keep the cadence in synch.