2lo8

Funny because upgrading from the 105 RD is probably the only component listed there that will actually make you faster (by a watt)

cydewaze

Cadence is 85-100 usually, and I do like tight spacing. The thing that I worried about with the compact big ring is that for the same speed, it would put me on one cog smaller, and as cogs get smaller, the jump between them gets bigger, so if you're still 2 teeth between each cog, it would be icky.

Now that I compare a 6800 cassette to mine, I see that it actually doesn't give me any more usable gears. It just adds the stupid 11 and another one near the bottom. I'd need to drop a buck fifty on a DA cassette to swap the 11 for something I'd use.

Maybe what I really need is the 50/34 with something like an 11-23 or 25. My current low gear (39x27) gives me 38.1 gear inches. A 34x23 would be a little taller at 39, so I'd probably be looking at an 11-25 which gives me 35.9. Then at least I'd have a 16t. But maybe with a 50t big ring, I wouldn't even be on that cog much.

What a pain in the rear this all is, but I'm glad I asked, because it's better than getting something I don't like. I think I probably need to go ride something with a compact to see how I like it.

2lo8

The 12-25 is a really tight cassette if you're willing to give up 50x11. Available down to 105 level too. I think Shimano is actually phasing out 11-23 with their second generation 11 speed.

12-13-14-15-16-17-18-19--21--23--25

dksix

Just an FYI in case you haven't checked. Ribble has the 6800 group for $486.79 Shimano Ultegra 6800 11 Speed Double Groupset - Components - Ribble Cycles that's about $80 less than Merlin has it listed. I emailed Ribble recently and asked about not having an option for a press-fit BB and they said if I contacted them they would sub a press-fit for the BSA.

cydewaze

Oh, that one would be perfect! I have no desire to lug around an 11t cog that I'll never use.

Good info. I'm still not sure if I'm going to do that or piece together something.

cydewaze

OK, so I remembered that I had sitting around a FSA Gossamer Compact that originally came on my wife's Serotta. She hated the shifting so I swapped it out for an Ultegra. I decided to toss this crankset on my bike and see how I liked the gearing. We'll assume that I can't tell the difference between her 170mm cranks and my 172.5mm usual length. Also keep in mind that I tend to over-analyze everything.

The good:

• a 50x17 combo is the perfect gear for me on the flats. At 95-ish rpm I can do 22mph, which is about right for me.
• I can stay in the big ring for anything less than 5% uphill grade
• there's enough low gear to climb the side of a building, although I'd change cassettes if I went compact.

The not as good:

• when in the 50x17, any shift, up or down, is a bigger jump than it was on the 53x, because the smaller the cogs in back get, the bigger the difference between each one.
• unless a different cassette changes things, I feel like I'm basically going to treat this like a 1x11 with 2 or 3 granny gears off the small ring. I doubt I'd even stay in that small ring beyond climbing, but maybe that's not a big deal.

So my conclusion is that if I had a compact, I'd really REALLY want a 16t cog, and ideally an 18t one as well. The good news is that the Shimano 6800 cassette has all the gears I need.

12-13-14-15-16-17-18-19-21-23-25

So it looks like that's the ideal setup for me. A little more low gear and nice, tight spacing right where I need it.

2lo8

You can also get that gear combo at 105 level too.

cydewaze

I actually plan to piece-meal it together, since there's no savings in ordering the complete groupset. I'll probably get a better FD and save on other components. On my two 9-sp bikes, one DA and the other 105, I'm sure I'd be hard-pressed to tell them apart blindfolded.

dr_lha

I've got over 4000 miles on mine, and it's as good as day one. Well apart from the hood being ripped from where I crashed, but that's a $5 fix, when I get around to it.

That's the first time I've heard someone bad-mouth 6800 mechanical, and I must say, I'm a little surprised.

BTW I wish there was a 12-28T cassette also. I ran 12-30T Ultegra 10 speed on my previous bike, and it was great.

Instead with get this 14-28T cassette, which I'll be honest, I'm a little tempted to try.

noodle soup

He "threw it away" , and replaced it with SRAM.

dr_lha

What are you implying?

noodle soup

I doubt he actually threw it away, and if he did I can't trust his decision making. JMO

cydewaze

I'm going to go out on a limb and assume that the new 6800 stuff will shift as good as (or better than) my old 9-sp DA stuff. And maybe save a little weight. My old DA7400 brake calipers are listed on Velobase at 432g. I think the 6800 set are 335 or something, so that's 100g there (not to mention the springs in my old brakes are shot, so the rear one won't release properly). But mostly I want to be done with the mix-and-match 9-sp/10-sp thing.

noodle soup

That is a very safe assumption

cydewaze

Got lucky today. Performance is having a huge sale so I stopped into our local one. They had three items in stock and are ordering the rest. The best part is that the manager gave me 20% off the entire lot because the shifters were taken off a stock bike for a customer who wanted to upgrade to DA. They were never ridden so I had no problem with it. Once I get the team perf rebate I'll be in it for under $500.

f4rrest

You'll definitely want the 16T with the compact chainrings, given your stated cruising speed.

I miss it on every single ride.

cydewaze

Yep! I'm getting the 12-25 which has 12-13-14-15-16-17-18-19-21-23-25.

I also ordered the medium cage RD, in case I ever want to drop the 11-32 out back for more serious climbing.

noodle soup

The 12-25 11spd cassette with a compact crankset is a great setup. It gives you corncob-like spacing, but gears that mere mortals need.

My old TT bike had a 12-19 8spd cassette that I loved for flat rides, but the 52-42 crankset made big climbs a challenge. Now I rarely find myself trying to find an easier gear that isn't there.

Maelochs

Now you have me wanting to save up for the 12-25. Do you guys work for Shimano?

cydewaze

Not to mention, it's much more of an ego boost to look down and see yourself in the middle of the cassette, rather than being semi cross-chained in a 53x19.

cydewaze

SRAM has an 11-25 that's close, but you use the 18: 11,12,13,14,15,16,17,19,21,23,25

For me, the 18 is far more useful than an 11.

Campy lists a 12-25 but I'll be damned if I can find a list of cog sizes for it.

Maelochs

Yeah, the Shimano range seems perfect with a compact---I spend the vast majority of my time between 12 and 19, and single steps in there make sense. 50x12 is a little low for a top gear, but for how often I would use it I could just spin faster.

I have 11-28 now, which is great for all-around but I don't need the lowest gears that much on most rides. I'd keep the 11-28 if I traveled anywhere where a highway overpass or bridge wasn't a "climb."

cydewaze

Finally got everything installed.







Needless to say, the shifting is amazing compared to the old, worn-out 9-sp stuff. The shifters don't rattle over bumps because the return springs aren't worn out, and I can actually run the brakes near the rims and have them actually release enough not to drag. Best $500-ish I've ever spent!

noodle soup

I suspected you would be happy with the new components. Any thoughts on the 12-25 cassette?

cydewaze

By the time I got is done and adjusted, I only had time to ride it around the block a few times, but I plan a short ride today after work, then a long one tomorrow. I'll post an update then.