munkymack

I recently moved up a fairly wicked hill, and would like some more climbing power, so I'm considering upgrading my baby, a parts bin special - Ross Centaur w/ standard 2x chainring, 7sp 11-34 cassette (with Deore XT long cage mountain derailleur) and downtube paddle shifters (7 speed index).

My plan was to put a compact crankset on this, but I think the front shifter paddle's internals might be broken, and the front derailleur isn't in great shape, so I might have to replace those as well if I stick with 2x.

I'm inspired by this Youtube video where he uses a generic 8-speed 11-42 cassette (converted to 7 using the old 12T cog) to turn his mountain bike into a 1x wide range 7 speed. (Shows it at 9:31, explains it at 19:54). I'm thinking this might be a better, cleaner solution.


Whether I replace the cranks with a 1x setup or switch to a compact crankset, I'll be building this out of the parts bin at the local bike co-op (apart from the things I absolutely have to buy new).

A couple of questions:
1. Would I be able to retain my old index paddle shifter (it matches the look of the bike, so I'd like to keep it - the front shifter I'd keep on for looks but it wouldn't be connected to anything)
2. Would I even need a derailleur extender, considering the fact that I already have a long cage derailleur on it?
3. Are there other issues that I'm not considering that might make this a dumb choice?

I'll add photos of the existing setup below, but would love advice before I head down to the bike co-op to start working on it. Thanks!

Commuter Bike:


Commuter: 11/34, Deore XT long cage.

Commuter: Standard 2x Crankset and Suntour front derailleur

Commuter: Sante 7 speed indexed paddle shifter

Iride01 

If you really want the best range of gears to climb with, then I don't know why you wouldn't go for a 3x with 9 maybe 10 on the rear. For 1x you really will have to consider some of the newer and more expensive offerings from Shimano or SRAM.

And even then I don't think you'll get the lower ratios you might want with out giving up the higher ratio's you might want for going down the other side.

Of course the rear spacing is pretty much going to dictate what you might be able to put on it.

Bill Kapaun

If you have "regular" commuting along with your "fairly wicked hill", going 1X is the last thing I'd do.
You don't specify what chain ring you want to use, but will assume small enough to use a 42T cog and barely get you up the hill?
This will result in rather wide jumps between your cruising gears where you'll probably find one gear too low, but the next higher gear too high too frequently.

Personally, I'd get a cheap 22-32-44 mountain triple and something like a 12-28 or 13-26 cassette. Largest cog being what will get you up the hill on the 22T ring.
A friction front should have enough travel if set up carefully.

munkymack

Right now I'm climbing the hill (which is about 3 blocks) in my small ring and biggest gear (39t x 34t, so a gear ratio of 1.15). I can make it up the hill, but I'd rather be less sweaty once I do.

But you are right. Running the numbers, if I do a 42t chainring for a 1.00 gear ratio at the high end, then the smallest gear on the proposed cassette (12t) would end up approx. equaling my current flat cruising gear (53t x 15t), with no way to go any lower if I want to pick up more velocity on a decline.

Thanks for talking it through with me, that's exactly what I needed. I think I'll stick with the original plan of going with a compact crankset...That way I get an extra bump in climbing power without sacrificing too much in my normal cruising gears.

Bill Kapaun

You've got higher & lower gears reversed. Lower for hills, higher for speed.
As far as "racing" down hills-
Most people are better served by conserving their energy for the uphill. The faster you go, air drag increases very disproportionately.
Tuck in and make yourself "aero" instead.
Have you practiced panic stops when doing high speed descents? After an embarrassing incident some years ago, I realized it gets much more difficult. OTJ training wasn't the best idea. I would have been better served if I had some experience.

dsbrantjr

Absolutely, if you need a wider range of gearing going to more front rings, not fewer, is the way to go. Or go with a compact double and coast downhill. I have triples on all of my bikes BTW.

bwilli88 

I rather enjoy 1x setups.

1x9, it works great. Shimano 12-36 9 speed, 42t chainring give me fairly evenly spaced gears with 33.3GI to 100GI.

munkymack

Yeah, I always end up doing that. I also consistently confuse my lady when I signal for a right turn but yell out "turning left" because I'm signalling with my left hand.

Oh, I coast down most hills...I'm just talking about slight decline, need a little extra speed to beat the light kind of velocity.

munkymack

I ended up sticking with the 2x. I dug around in the parts bin at the bike co-op and found some 110 BCD Deore cranks and two non-branded chainrings (50t and 34t) that were in pretty good shape. The ride home that night was Interesting, as I had to figure out new cruising gears, but the final three blocks were just a bit more relaxed, which is what I was aiming for.

Thanks everyone for the advice!