Road Cycling - 36 vs. 34: opinions needed

I need to make up my mind...

Right now my Tarmac has 50/36 at the front. I have an option of switching 36 to 34 but I just can't decide. Part of the reason is that the bike is brand new (I had it for 4 days only). The other part is that on my other bike I have triple.

Last Saturday and Sunday I rode a few hilly roads (for those of you in SFBA area: Hwy 84 up to Skyline, and Metcaf rd) trying to make it more clear. The first one (Hwy 84) is not as steep as second one (Metcaf). I spend most of the time sitting while climbing the first road. But I was standing most of the time climbing second. Metcaf isn't long (about 2 miles) with grades of 10-11%. My concern is that on longer steep roads (Sierra rd. like) I won't be able to stand for long time. On the other hand, to some degree this is a matter of fit: if I switch to 34 I'll be making my life easier :).

Why not keep the 36 and buy the 34? If you want have the LBS make the swap for you then learn to swap out to the 36 after a few months of climbing and see if you're able to climb with the 36?

Just a suggestion.

hmm, I haven't thought about this one. thanks!

I was like you. Bike came with 36. Everybody talked about a 34. Swapped it. Kept dropping my chain for no apparent reason, hated the large jump. Switched back to 36t. Very happy now.

Here is a chart of gear inches:

----------50-----------36-----------34
11--------119.54-------86.07--------81.29
12--------109.58-------78.90--------74.51
13--------101.15-------72.83--------68.78
14--------93.93--------67.63--------63.87
15--------87.66--------63.12--------59.61
16--------82.19--------59.17--------55.89
17--------77.35--------55.69--------52.60
18--------73.05--------52.60--------49.68
19--------69.21--------49.83--------47.06
20--------65.75--------47.34--------44.71
21--------62.62--------45.08--------42.58
22--------59.77--------43.04--------40.64
23--------57.17--------41.16--------38.88
24--------54.79--------39.45--------37.26
25--------52.60--------37.87--------35.77
26--------50.58--------36.41--------34.39

If you're going to be doing 10%+ hills often then take the 34 for certain, they should be agonising enough as is without a triple ;)

Don't let ego get in the way of your gearing. If you think a 34 would be better for you, get one, but keep in mind the monster jump to the big ring.

What cassette are you riding? That might be a better place to attack the problem.

Last Saturday and Sunday I rode a few hilly roads (for those of you in SFBA area: Hwy 84 up to Skyline, and Metcaf rd) trying to make it more clear. The first one (Hwy 84) is not as steep as second one (Metcaf). I spend most of the time sitting while climbing the first road. But I was standing most of the time climbing second. Metcaf isn't long (about 2 miles) with grades of 10-11%. My concern is that on longer steep roads (Sierra rd. like) I won't be able to stand for long time. On the other hand, to some degree this is a matter of fit: if I switch to 34 I'll be making my life easier :).

If you are having a hard time on Metcalf, don't feel bad. It's not an easy climb. Pretty much everyone needs to get out of the saddle for significant portions of that. I very seriously doubt that a 34 chainring will make much actual difference other than in your head. I'd say keep the 36 and just keep grunting it out on the hills. You'll get better at it (but remember the LeMond quote that 'it never gets easier, you just get faster').

As to Hwy 84: blecchh! That's a crappy climb...too much traffic and not enough room for cyclists going up. Old La Honda is a much better climb, plus you can gauge your own progress as well as compare your ability to other cyclists in the area by timing yourself (bridge-to-stop-sign). Coming *down* 84 is fun, though.

My own Two Cents....keep the 36 and play with cassettes if you have to.....the jump between the 34 and the 50 is big & awkward (to me).......I actually went back to a triple (50-39-30) from a compact and now I feel I have the best of both worlds.....95% of the time the 50-39 combined with an 11-28 cassette gives me what I need, and for the really big and/or long hills I have the 30t......plus the shifting is smoother than any of the compacts I ran.

I think the Tarmac compact comes with 12-27, is that right? If so, it's the same gearing that I have on my Roubaix. I hate 10% grades, but they're doable. If I had to maintain that for a long time or go much steeper, I'd want a 34 (if not a triple!). I find the 36 ring is great for the rollers I have around here--nothing like SFBA terrain.

If your big ring is a 50, I'd stick with the 36 for two reasons. The first is that 36 is generally a more useful ring than a 34. The second is that if you go 50/34, except when you are on hills, you may find that you are somewhat between rings. Compacts have great range, but if your cruising speed on the flats is around 20mph, you may find that you're too close to one end of the cassette or the other.

If you go with a 34, consider a 48 on the big ring -- this will put less of a gap between the rings and improve shifting. When you are on the flats, you'll be able to cruise in the big ring closer to the middle of the cassette. It is possible to spin out, but you have to be going over 40mph (i.e. down a hill).

Frankly, it's much handier to have gears that you can use all the time than ones that barely ever get used or provide little benefit when they are.

I like my 36, but I've not used a 34. What cassette are you running?

I have 12-25 cassette right now. No plans to changet, but it's always an option.
I haven't ride OLH on this bike yet, but it's on my "to-do" list for this week. As well as Page Mill.

I have 12-25 cassette right now. No plans to changet, but it's always an option.
I haven't ride OLH on this bike yet, but it's on my "to-do" list for this week. As well as Page Mill.
Page Mill will test you, for sure...especially "the wall" at the top, just when you think you're almost done :D

36

Page Mill will test you, for sure...especially "the wall" at the top, just when you think you're almost done :D

that's precisely the plan ;)

50/36 with a 12-27 is a great combo.

well, I'm not sure if I want 12-27. I understand that this is an "ego-driven" decision, but I'll keep 12-25 for now.
I'll post an update later today after I come back from Page Mill :)

I could see how a 34 over a 36 would be usefull for climbing, however for everything else I find the jump from 50 to 34 to be to much. Another possibility would be an MTB rear der and an MTB wide range cassette.

I have a bike with a 50-34 compact. Since I came to that from a standard road double background (53/39), the first thing I did was to order a 36 to lessen the jump from the big ring to the small ring. By the time I got the new ring, though, I had adjusted pretty well to the 34. Since I do a fair amount of climbing, it'll probably stay on there most of the time, with the option to put the 36 on when I know I won't be heading to the mountains for a bit.

Climbing in NC is much more pleasant with the 50-34 and an 12-27 than it was on my previous setup! Since I'm a spinner by nature, this gearing allows me to perform much better than I was previously able to. (When I'm not in the mountains, I run an 11-23, so I don't lose out on top end and close ratios).

well, I'm not sure if I want 12-27. I understand that this is an "ego-driven" decision, but I'll keep 12-25 for now.
I'll post an update later today after I come back from Page Mill :)

Ok...you don't want to get a 12-27 due to ego factors, but you'll consider getting a 34T chainring....

:rolleyes:

With the 34 you'll get a gearing that is about 2" lower than your current lowest. Considering the overlap with the 36 aqnd 50, you aren't really losing any gearing on the higher end of your gear spectrum. So with the 34 you'll get a wider range of gearing options.

The only real issue is the jump from a 50 to a 34, which may or may not be an issue for you or your bike.

Ok...you don't want to get a 12-27 due to ego factors, but you'll consider getting a 34T chainring....

:rolleyes:

That's nothing.

I have a 50-34x11-23.

That's nothing.

I have a 50-34x11-23.

You live in Wisconsin though.

I was looking at getting the Shimano R700, is a 36 even an option with that one?

You live in Wisconsin though.

You saying I don't ride hills (http://www.dairylanddare.com/)?

(Ok, I used a 25 on that ride)

Ok here is my input. If you currently have a 12-25 then get a 12-27 and keep the 36t. Don't forget that the rings are matched...with that 36t inner you have an outer designed to shift well with a 36t inner...have a look at it and it will have some comment about this engraved on it. The ramps and pins are different for the 50 that works with the 34t and the result will be a loss of shifting performance. Your other option would be to get an aftermarket cassette as someone else mentioned that is 11-28 thus giving you an even wider range and even lower bottom end.

Honestly I never had an issue with my Roubaix with a 50/36 and a 13-26 (I run Campy) and I have many hills in my area that are over 10% grades and longer climbs that avg in the 7%-9% range and I am a clydesdale.

I had the same issues with the large drop. The 34 was just useless for me; I never shifted into it except when stopping. This is with a 12-25 cassette.

I have a 38 in the mail right now, which should be great as it's pretty flat around here unless you go looking for hills. I really wish my bike didn't come with a compact at all...

Personally I think you should go with the 36. 34 is very small and no matter how good your adjustments are I guarantee you will drop the chain on a hill at some point. I'd change the cassette if you wanted one more "fall-back" gear.

You saying I don't ride hills (http://www.dairylanddare.com/)?

(Ok, I used a 25 on that ride)

Ok, so your hills on that ride look a lot like around here....lots of 100-400 foot climbs....

Sorry, I was thinking of Minnesota.

I went from a 36 to a 34, it was most helpful. I have a 25-12 but will change to a 25-11 shortly when I get my new frame.

I went from a 36 to a 34, it was most helpful. I have a 25-12 but will change to a 25-11 shortly when I get my new frame.

Where did you find the 25-11? Seems to be a rare combo.

I run 50/34 on both my bikes, one a 12-27, one a 12-28. I find I can big-ring most rides, unless I head west (i.e. the climbs of the front range and beyond), where I much prefer the 34 over the 36; the legs just feel better going a few rpms faster....

Where did you find the 25-11? Seems to be a rare combo.

Campy......I believe it is a new combo this year....available in Record and Chorus..

Ok...you don't want to get a 12-27 due to ego factors, but you'll consider getting a 34T chainring....

:rolleyes:
:)
well, if you'll read my original post you'll see that ego is preventing me from saying "I'm switching to 34 right now" :).

anyway. I just came back from riding Page Mill. Bottom to top in almost 56 minutes (personal best with triple is slightly shy of 50 minutes). Not bad. More important, no leg or knee pain. I found myself standing more than usual (not all the way as it happened on Metcalf), but to my surprise it actually felt pretty good.

Looks like I'm going to keep 36.

That's nothing.

I have a 50-34x11-23.


me too!!! i Also use an 11-27 9 speed...I'm keeping the 11 b/c by buds always drop the hammer on the down hills and think its funny to see me spin out...