Yet another compact vs triple thread

[Borbus]

This is yet another compact vs triple thread, but I have a concern that I couldn't find addressed in any of the other threads.

I like the idea of a compact because I haven't used the granny ring on my mountain bike for years, so I don't think I really need one on a road bike. But what concerns me is the rather large "gap" in the gears when shifting from the small to big ring. On my mountain bike when I shift up on the chainring I downshift by one on the rear (7sp) to get a smooth change. It seems that with a 10sp rear and a compact I'd need to downshift by 4 gears on the back to get a smooth change. Can the Shimano 105 levers do 4 at once? Or is this not really a problem?

 

[Chris James]

Your granny ring on your mountain bike is probably something like a 22 tooth. The middle ring is probably 32 teeth.

A road granny is 30 teeth and the wheels are slightly bigger, increasing the gearing again.

So road triples are 'harder' than MTB triples.

You can change down 3 cogs at a go on 105, although only up in single increments.

 

[Borbus]

Actually I have a 50-39-30 chainset on my "mountain bike". It used to be a mountain bike but now it's more like a heavy road bike...

 

[aberal]

My triple drops from a 42 middle ring to a 30 small ring, a difference of 12 teeth. A compact will drop from a 50 large ring to a 34 or 36 small ring, a difference of 14-16 teeth. What this really boils down to is that I often have to shift up a gear or two the instant I drop onto the small chainring to maintain cadence. With a compact you may have to shift up two or three. It's no big deal, you get used to it very quickly. If I could wave a magic wand I would change to a compact in an instant. Last week on the very, very switchbackie Bealach Beag, the constant changing between the three front rings was a real pain in the rear end.

 

[Chris James]

I'm quite keen on my triple.

I find the 42 tooth chainring a very good all purpose ride. I can climb fairly steady hills on the 42 ring, maybe 1 in 10s. Anything steeper or long climbs and I drop to the small ring.

I previously had a bike with a 48/36 double and I found that I was constantly shifting front rings as 36 was too easy and 48 too hard. It was quite irritating. I would have though this would be even worse with a 50/34. I would spend all my time running terrible chainlines.

I think I would prefer a standard double and MTFU!

But each to their own.

 

[TrevorM]

I have a touring bike with 26, 36, 48 triple. Like you I never use the granny ring (unless heavy touring in mountains). But I was constantly changing between the 36 and 48 and adjusting the back gears each time on normal road rides.

My road bike is a standard compact double (34, 50) with 10 spd cassette. I only ever use the smaller ring when climbing and only change to big as I come off the climb and cadence increases. At that point the large increase is useful to accelerate on the downhill. If its flat off the climb I sometimes drop down 1 gear at the back as I change onto the big ring. Its not really a problem.