speedlever

I had a thread here recently about compact doubles and triples and here are some more thoughts.

My incoming bike is going to be a compact double (50/34 and an 11/26-10 spd cassette). I'm used to running a standard triple (52-39-30 and a 12-25 10 spd cassette). For the last 500+ miles I've been running a CD on a borrowed bike and am more or less used to it, but find I'm still fumbling with gear selection from time to time.

Here's where I run into a problem with a CD setup. I like to keep my cadence in the 90-100 range, more or less. If I've been in my mid chainring climbing a hill and have a level run for a while, I like to shift into my big chainring at an appropriate point. Typically, that's around 22 mph where I do that doubleshift.

On the triple, I'm running 39/14 at 100 rpm which is right at 22mph. A double shift with a full handful of cassette (3 cog) change and I'm at 90 rpm and the same speed.

Sheldon's gear chart looks like this:

39/14 - 21.8 mph @ 100 rpm
dbl shift to 52/17 - 21.5 mph @ 90 rpm, perfect to continue to build speed on the level or downslope.

It has worked very well for me. Hope it makes sense to you.

Now on a CD setup, I seem to have to do a double shift and add a 4 cog shift in the rear. That's a handful plus 1 to accomplish the same thing.

Sheldon's calculator shows:

34/12 - 22.2 mph @ 100 rpm
dbl shift to 50/15 - 23.5 mph @ 90 rpm. Which means I'm gonna be well under 90 rpm until speed builds back up. Or I can shift one more cog to the 17t which is 20.7 mph at 90 rpm.

Perhaps I could modify my technique a bit and run up to 105 rpm or so before changing so as not to get below 90. Not that there's anything magic about 90 rpm, but I've found that the more I bike, the more I like higher rpms. I'll often be in the 115 range spinning up a (short) hill.

But do you see what I mean? With a max cog shift of 3 with a full shift, the triple setup seems perfect for me. I will admit that in actual practice, the reality may not be as severe an impact as this post makes it seem.

But I wanted to get your thoughts on riding techniques and see if I need to peek outside my comfort zone and expand my knowledge and experience some more.

Is this much ado about nothing?

melville

You're thinking too much about it. Just go to the big ring a bit earlier, so you're using the 19 or even the 21 cog, and fewer shifts will be necessary to get the gearing jump you want.

You should also get shifters that go more than 3 at a time.

speedlever

Heheh... probably so. I'm a bit frustrated waiting on the bike to arrive.. it was supposed to have been here earlier this week.

Are there shifters that go more than 3 cogs at a time?

melville

Never had a problem grabbing all five (I'm old!) with downtube shifters, bar-ends, or thumbshifters. Even works with all seven shifts on an 8S hub, and would probably do 10S just fine.

speedlever

I had a top tube shifter on my old Schwinn Collegiate (5 spd). Otherwise, it's been indexed thumb shifters on my hybrid or STI shifters on my road bike. The Collegiate is long gone, so I don't remember what I could do with it. The others are max 3 at a time.

Ah well.. no big deal.

DMF 

Much ado about nothing? No, I don't think it is.

The triple suits you fine. Now you have to change technique in order to use a different setup. The question you should ask is, What does the CD give you that the triple doesn't? If it doesn't counterbalance what the CD takes away, you're trading down. That's all there is to it.

Now, if you're asking whether you should be happy about trading down, that's a question that only you can answer.

Al1943

Another possibility would be a 50/36 compact with possibly a bigger cassette. Shifting from a 50 to a 36 would require fewer shifts in the back.

Al

speedlever

Fair enough. Maybe an old dog can learn a new trick. Only time will tell.

speedlever

That is true. But I still get confused as to what changes I can make without having to change the STI shifters, DRs, etc.

The interplay between the components is still a mystery to me.

With the stock components, I don't know what changes I can make without adversely affecting the operation of the stock shifters and deraillers. I'd prefer not to change them.

For now, I'm gonna leave it stock.

John E

... or even a 48-36 or 46-36 combination. Without swapping over to a compact crankset, one can also try something like 48-38, which, with a 28T granny ring, was a popular mountain combination for many years.

I still like my old-school combination of an 8-tooth drop in front and a 2-tooth progression in back. One can work quickly through the gears as needed, then double-shift to fine-tune while cruising. 50-42 / 14-16-18-20-23-26 works well, as does 48-40 / 13-15-17-19-22 ... .