RobbieTunes

Id rather kiss Katy Perry, but it’s interesting.

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1985 Cannondale ST-400

When I upgraded my ST-400 from its original components a couple of years ago I combined some vintage ideas with newer ones. So now it has 27" wheels with 9-speed hubs and a 3x9 half-step plus granny drivetrain. I have considered reducing it to downshift levers (I actually have a set of Microshift friction/index DT levers) and aero brake levers to follow a more vintage aesthetic, but it seems to work pretty well as-is.

davester

The original purpose of half-step gearing was to provide reasonably sized steps for widely spaced 5-speed (or less) freewheels. I don't quite understand the point of using half-step (or triples for that matter) for 9- and 10-speed cassettes as a few of the posters above have suggested. The percentage differences for those half-steps must be miniscule. Can you even detect that you've changed gears?

John E

Half-step or its relative, 1.5 step/"Alpine," makes a lot of sense with 8 cogs in back. It depends on how much range you need and how tight a ratio progression you favor.

On my mountain bike I use 48-40-28 / 12-13-15-17-19-21-24-28, for a beautiful 1.5-step-plus-granny. If I I ever convert to 9 speeds, I plan to add a 32T to the bottom end and keep all other chainring and cog sizes the same.

What I really like about half or 1.5 step is that most of the time I can simply skip a ratio and just move from cog to cog, but when I need in-between trimming, it is easily accomplished with a double shift, which is trivial to accomplish with thumbies or barcons and not bad with downtube levers.


True anecdote about "can you even detect that you've changed gears?": I copied the Nishiki Road Compe stock 1.5-step gearing, 54-44/14-16-18-21-24, for the 1972 Los Angeles Wheelmen Double Century. This was Nishiki's answer to the 52-42/14-16-18-21-24 combination that was becoming popular on European racing bikes. I downshifted as I approached a gentle upslope and passed a couple of riders, one of whom said, "He just shifted across his whole range, and it probably made about two gear-inches of difference."

HTupolev

Not all modern cassettes have tight spacing. Some are mostly just much wider-ranged. The biggest hindrance is really how evenly-stepped they are, but that's not always a problem. Take a look at the 9-speed Shimano 11-36, for instance: 11-13-15-17-20-23-26-30-36. That half-steps fairly well with somewhere around an 8% difference between rings. (It doesn't 1.5-step very well, though: the gaps on the ends are too big compared with the gaps in the middle.)

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I agree that the steps kind of lose their elegance when paired with a freewheel over seven speeds. It does produce steps that are like a very tight freewheel. So now I can feel like a racer on the flats, and a creeper on the hills. :-)

Road Fan

Very good! Slightly better would be to go 30-26-22 rather than 30-27-23, but the difference is very small. You want the actual step ratios divided by the ideal step ratio to cluster around 1, and the number of teeth different to increase monotonicly. Mine is 2-3-3-4-4, where yours is 2-3-4-4-3.
In this case it makes almost no difference in the gearing pattern.

Classtime 

Has any one played with a calculator to find a 9 speed or more range that would make sense using a 1/2 step in the front. Maybe with modern chains and chainrings you could do it and leave out the Granny. In my limited experience with 5 speed 1/2 step + Granny, I could use all cogs with either of the large chain rings. The only combo that sounded like trouble was the Granny ring and small cog but that combo was not needed.

BUT, There is nothing classic about 9, 10, 11, or 12 speed unless it is a corn cob. I think 1/2 step plus Granny 5 speed is classic and elegant.

bikingshearer 

You've seen how big I am and how amazingly (not) fast I climb up many of the same limbs you do. I am a walking, talking, pedaling epitome of the point.

smontanaro 

It seems unlikely you would find anything suitable. Think about the steps on a 14-28 five-speed freewheel. They are basically two gear changes apart, I think about a 20% jump between cogs. OTOH, the change in front on a 47-50 is one change. To preserve those properties with a six-speed you might add a 34 (just guessing) up top. Maybe a 13t small cog (but will you use it unless you reduce your chainring sizes?). To keep adding cogs, I suspect you might be limited to the big end. How big do those cogs need to be to maintain a 20% change from cog to cog? The largest cog in a nine-speed setup would probably look like the hubcap from a '57 Caddy.

mountaindave 

About the largest single sprocket one can find is a 34t - it’s on my 7s half-step bike (it starts at 11t). Any cassette beyond 8s (and most Shimano/sram 8s for that matter) is going to employ spiders for at least the largest three sprockets so there will be no mix and matching. It takes mixing two or more cassettes to get what you want.

My personal favorite is 50/45+(28, 26 or 24) paired with 14-17-21-26-32. This is a hard FW to find, but they existed. (It drives me crazy to see how many touring bikes came with half step cranksets improperly paired with regular FW’s, but I digress.) One can make a 6s system by adding an 11t (only possible with certain hubs) or 12t high end.

Drifting back to the question of shifting: DT or bar end. I prefer bar end, but I’m biased that way with or without half step, so take that with a grain of salt. I also slightly prefer indexed shifting, especially with more sprockets in back.

More drift: Shimano’s 7s bar end came with a little plastic clip (rare as hen’s teeth) that inserted into the cable routing track to change the cable pull from 7s to 6s. The cool thing is that 6s and 5s use the same sprocket spacing and a 6s shifter can be used to index with standard 5s FW’s! (Another alternative is to mount 6s DT levers on bar end pods.)

After all that ranting, I have to be honest: I find that I very rarely use the half step on my rando-ized Trek, but it is nice to have when I need it. I use it much more frequently on my go-fast 7s half-step RB-1 which I suppose makes sense because I’m usually hammering and trying to maintain cadence.

Oh, and when you start obsessing over gain ratios and want to find the ideal setup, let me know and I’ll send you the spreadsheet coding to completely lose your mind.

L134 

Yes. To me, the key is to forget about the original purpose. My purpose is to fine tune my cadence for grade, wind, or simply how I’m feeling, and sometimes the shift is just about improving the chain line. I like to shift, I friction shift a lot half step or not. I can get a wide, ride anywhere range and closely spaced gearing.

smontanaro 

L134 I think your use of the term "half-step gearing" muddies things because what you describe seems distinctly different than what the term typically means. There's nothing wrong with what you're doing. It's just not half-step gearing. At its simplest, half-step gearing means something like a 10% difference between the two chainrings and about 20% difference between the rear cogs. Something like this. (Actually, 46-50 up front would be closer to what I describe, but 47-50 was common as I understand it. It's how my Frejus was equipped.)

L134 

45/42/26 with a 12-32 9 speed cassette. 47/44/26 also good. Give almost perfect half steps? I acknowledge not using it for the “original purpose.” In city traffic I have the “simplicity” of a 1x9. For longer rides or touring I can do my fine tuning and take on steep sustained climbs. Why would this muddy the waters? Half step to me means the shift up or down up front gives me a step half as big as the shift in back? So what if the percentages are 5% and 10% instead of 10% and 20%? That seems rather arbitrary and limiting to me. Is it even possible to get a 20% difference in cogs on a 9 speed cassette? If not, then by your definition there can be no such thing as half-step plus granny with a 9 speed, in which case the question that I answered is moot?

Unfortunately the scarcity of odd tooth count chain rings is the most limiting factor.

HTupolev

Half-step means that the ratio difference between the rings is around half the size as the ratio difference between the cogs, so that you can use front shifts to interleave the ratio gaps in the rear shifts. A 10% front difference paired to ~20% rear differences is half-step, but so is an 8% front difference paired to ~16% rear differences.

If someone thinks that the 1-tooth jumps in their 13-14-15-16-17 freewheel are just too big, and solves the issue with a 60-58 crankset, that... well, it would be unusual and draw a lot of funny looks, but it would be half-step.

droppedandlost 

Here's one that works pretty well.

Classtime 

Nice! Now if the chain can swing from the 12 to the 32 from both chainrings, that is pretty cool. And that cassette is a stock item? And who doesn't have a 42 and a 39 laying around! Bravo!