nick_a

Hi all,

I'm considering an arrangement for my hilly commute, where I would run 46-38-28 in front, with 9sp 12-36 in rear. Is this folly?

Thanks.

BobbyG

I've never been good at figuring gear ratios, but I've been commuting in hilly Colorado Springs for 30 years and a wider spread of gear ratios is always better. I have five bikes and have modified three for lower gearing while keeping or extending the highest gearing (for high-speed descents). The lower gears are especially important now that I'm in my 60s and straining hard against pedals is not good for my knees and other body parts.

I bought a used set of wheels for my 26" studded snow tires which came with one of those crazy-low bail-out gears, which felt comically low with my snow-bike's wide-range triple, until that first time I needed to ascend a steep blocks-long hill against a still winter head-wind in the snow with a full commute bag made heavier by winter-weight office clothes. Sure, it required a fair amount of spinning to reach only 4mph, but my knees were happy, and I didn't have to dismount and try to push the bike uphill a few streets at 2mph.

My latest purchase is a light, close-geared road bike with a compact double and I am going to figure out if I can get a significantly smaller ring up front, or a wider spread in back.

pdlamb

Only you can say; I suspect your low gear may be lower than you really need, but when you've got a heavy load and hit a steep hill at the end of the work day, you may be very happy to have it.

OTOH, gearing like this will make weekend rides a breeze when you venture into the foothills and perhaps even Skyline Drive/BRP.

timdow

28 ring 36 cog gets you down to 21.1 gear inches, which should be plenty low enough. The stepping isn't bad, either. I personally would go with 26/36/48, but I carry a heavy load on occasion.

Gear calculator:
https://www.sheldonbrown.com/gear-calc.html

Darth Lefty 

Your described setup is not half step. I'm not really seeing how it's different from most inexpensive hybrids. It will be fine.

Korina

Ooo, I see you have a Privateer. How do you like it?

grolby

This isn't half step gearing, the gap between the middle and large chainrings is slightly smaller than typical these days but not by a lot. Half step gearing would have those rings very close in size, no more than 4 teeth difference and maybe less. That said, no folly here, this will work just fine. Half step gearing is a relic of days long gone when freewheels had many fewer sprockets and front derailleurs weren't very good for large shifts. Most people find it too annoying to actually use properly and it's not really necessary with modern rear sprocket clusters and powerful, effective front derailleurs, and that's why it isn't really a thing on modern bikes. You would have a hard time even setting up true half step gearing with modern components - most cassettes are too closely spaced to really make it work.

nick_a

Thanks all for your input. I'm going to start out with 48-34-28 up front and see how I do.

Edited to add, I have a pretty brutal uphill climb out of the city to my house on the way home, which is what prompted the change in the first place. 46-34 just wasn't cutting it, and hot weather is coming.

Darth Lefty 

You can find a zillion cranks that are 48-38-28. Sometimes two teeth off from there. They are fine. The 10-12 tooth mid-top shift is what the triple derailleur is designed for. What are you trying to do? Your choices are strange.

nick_a

Ha why thank you! I started with a 28-38-48 Sugino VP triple from my parts bin. The 10-tooth difference wasn't enough between the two largest rings for my ultegra FD (also on-hand) to shift to the 48.

So, I ordered a modern bog-standard Altus FD, and the cage is too wide for the Q of the cranks and couldn't shift to the 48 without interfering with the DS crank.

Thus, 28-34-48.

nick_a

IMHO, it's kind of a sleeper out there for anyone that may be looking into Surly or Marin steel bikes, but a bit cheaper. The geometry is almost identical to the Surly Cross Check, with a taller head tube to allow for more upright riding if that's how you want to build it up. It can fit 700x42 slicks, and any kind of rack. It was my "poor man's riv" before I bit the bullet and got the real thing, and now it's my commute/around town/basket with sweep bars bike. I've put about 3500 miles on mine, and have found it to be extremely versatile, comfortable, and useful.

79pmooney

Can't resist - I'm old enough for a two steppin' granny.

My three geared bike have:

The good bike - 50-38-24 with a 9-speed Campy that I between 13-23 and 12 (to 14) -28 depending on ride, wheel, conditioning and mood.
Raleigh Competition - 52-42-24 with 13-26 7-speed
Pro Miyata - 52-42-30 with 13-26 7-speed. (Campy Chorus crankset. Haven't looked into BCDs and chainring options yet. It is pure race so muscling is appropriate.)

I've never worked out the steps. They are probably horrible. I shift racing style, trying to stay in the ring up front that allows me to tackle what's in front of me with the rear.

Darth Lefty 

I've seen a Sugino triple crank like that with really close rings on a Rivendell. But it also had friction shifters and a double type FD. Not a recipe for good shifting but that's sort of their thing

Leisesturm

If the cage width of the FD is causing interference with the DS crank, I don't see how altering the tooth counts of the chainrings is going to help! You might look at the high limit screw, or BB spindle length even, but if a 28,34,48 will work, then so will a 28,38,48 unit triple, and that will be massively easier to find.

nick_a

Not wanting to buy another FD, I went with a tooth count difference that works with the Ultegra FD I had on hand. BB spindle length has no impact over the distance between crank and chainring.

The setup I went with works great, and I'm not clear on why it seemingly confuses and upsets you so much.

Leisesturm

Upset? No. I'm not upset. I thought there was a problem implied in the o.p. If you have it all sorted why are any of us here?