Compact or mid compact with 11-28 or 12-25?

I've just gone from a compact to semi and the change is only evident on 20% plus climbs which means more effort and a slightly lower cadence than I previously enjoyed but also not suffering the embarrassment of dismounting and walking up anything I've climbed before on a compact.

when I bought my new bike I did think along your lines but after heading out and doing the steepest local rides and there's plenty the only conclusion I could draw was the whole compact/semi is marketing BS as I'm not the strongest rider.

hhmmm.....

I dont think the bike makes the difference to be honest.

Is a dogma a aero or climbing bike? Because Froome goes up hill quite well and Viviani wins sprints on it.
Roubaix was just won on a aero bike, beating specific bikes 'made' for cobbles.

I would agree with Imposter, its the gearing that changes the use of a bike, not the frame I am afraid.
Its called marketing.

rafregt1 wrote:

I suppose my thoughts are this...

Do I want to stop the bike from being used from its maximal potential by going for a climbing set up?

Any advice or thoughts from others that have knowledge or experience would be greatly appreciated.

With thanks.....

Well there's nothing to stop you from buying more than one cassette? Size you chain for an 11-28 then you can put the 12-25 on when you're wanting to ride the flats.

As for the semi-compact, at the risk of starting another 100 page thread. Well is 36-28 a low enough gear for you to do the climbing you want to do? Only you can answer that question, nobody on here can, including me.

Edit: Seems exactly the same advice was posted at the same time!

Different viewpoint: I have several bikes, but one in particular which I use only for laps of Regent's Park. It's an 'aero' bike and I run a 52/36 with a 12-25. I can get it back up Swains Lane on the way home, but not enjoyably. The rest of its component choices reflect this singular role (Zipp 808s, 3T Zefiro bars etc) and as a result it's not that light either. It would take a good deal of work to make it into something it would be pleasant to use for a Hertfordshire club run, so I use a different bike for that. The result is that for its intended purpose it's very focused and (by my standards) fast - certainly faster on the flat for the same power output than my climbing bike. If you can afford it, having bikes that are specialised to a purpose is effective; nonetheless there are plenty of people who'd go round RP faster than me even if they used my climbing bike, and doubtless no shortage who'd outclimb me even if they used my RP bike. This has to be about your own performance and pleasure.

bsharp77 wrote:

If I read the OP's post correctly, I don't think he's saying the bike will make a difference - he is wondering what gearing to use to get the most out of the bike and not compromise on speed.

Gearing depends on fitness, so the only person who can answer that is the OP himself...

As everyone said it depends entirely on what you need and how often you really need a really low gear. For me I've used compact, semi compacts and full size chain sets but always end up with a similar gear range. Used to live in Surrey and always used a 53/39 with a 12/23 and pretty much used all my gears at some point. Took that setup to the Alpes and found I needed a lower gear so bought a 13-26 which was lowest available. Then 10s came out and I got a 12-25 which was perfect for me. Bought another bike and decided to try a compact but found it a real pain with a 12-25 as I needed a bigger gear and rarely used the little ring so fitted an 11-23 which was fine; basically the same hearing as the 53/39 12-25 combo so that's the gearing range I need. Moved to Norfolk and have recently put on a semi compact with a 12-25 but haven't needed the little ring so am thinking of putting on a 11-23.
To me you want gears that you will use, no point carrying gears you don't need and you can always put on a different cassette if you plan to ride a really tough course. My point is that semi compact, compact etc is irrelevant, you just need to work out the ratios you need and purchase accordingly.

I'd look at it this way...

How often will you spin out a 50-11? If the answer is regularly, get the 52... If the answer is (almost) never, may as well buy the compact because you almost certainly WILL use the 34x28 somewhen... and you'll probably be glad you've got it when you do.

Choice of gears is a pretty personal choice. I've got both of my main bikes set up as 52-36 on the front and a 28 speed cog on the back, and this suits me and the terrain I ride on. I don't see the advantages of semi-compact as being about the big ring, more that I prefer tackling my local climbs on a 36 tooth ring.

I have found myself wishing for a few more gears on some of the long, steep climbs in the Peak District, so might well get myself a compact chainset for the Summer. Alternatively, if you have a long-cage derailleur, you actually get a wider range of gears with a 52-36 and a 32 tooth cassette that you get with a 50-34 and a 28 cog. Now we're (mostly on 11 speed) I don't think the gaps between are such a big deal.

^ He means regent's park.

It's not really about 'spinning out' on 50x11. I have a 50x11 and it's when you want a good cadence to suit your own preferences with sufficient resistance to really hammer it in sprints and, possibly get a good chainline.

I would say there are times when in a chaingang when we're smashing it and I want a heavy enough gear to keep rolling along and I want to turn my legs more slowly when in the draft to give them a break! 50x12 has definitely been insufficient at times.

That said, if you mostly ride solo, then 50x12 is probably fine.