Fifty Plus (50+) - Doubles vs Triples

Cranks, not drinks:) Since getting the cheapo Windsor dialed in I have been putting miles on both bikes and have had the opportunity to closely compare riding a triple to a double. I had always assumed that riding a triple would be easier than a double. Ah, not so Grasshopper! I live in a hilly area (edge of the Blackstone Valley), they can be short and steep, long and steep, or long and gradual. There are especially alot of those awful 'false flats'.

So here is my highly analytical findings based on my power capabilities, which are about equal to the battery in the cyclometer.

When riding the triple (52/42/30, 9-speed 12-25 cassette) I stay in the 42 most of the time just because I hate the feel of the granny gear, but do have to use it occassionally. The problem is that on those long gradual slopes the 42/23 or even 42/25 gets tiring and my cadence suffers. These are those hills that are a little too much for the 42 but not enough to justify the granny.

Conversly, when riding the double (53/39, 7-speed 12-28 cassette) the 39 works well for those same slopes, but, I run into the opposite problem where the 53 is just a little big and the 39 a little small for the flats.

So here is what I'm thinking. Realize that I am not a speed demon and never will be.

For the double: Change the outer ring to a 48T so it's more like a double trekking crank, or just convert it to a trekking crank (48/38/28).

For the triple: Change the middle ring to a 39T and the outer to a 50T, or again just install a 48/38/28.

Any thoughts? Has anyone done something like this. Geez, it would be nice to know this stuff when purchasing. I guess what I'm attempting is to come up with my own semi-compact crank.

Tim,

I think the mix of gears one needs is a combination of what kind of grades one usually rides and how strong one is and whether you like to sit and spin or stand and mash.

That being said, I have similar feelings as you do. Instead of a 48/38/28, I would be tempted to go with a 52/40/28. I have a bike set up with a 48/38/28 for mountainous terrain and it works great. I have never had a 50/40/28 so I don't know if I REALLY would like it that much.

I think you are right though, if you have a triple, the small ring is pretty much limited to a few gears so it is pretty much there with its gears for extreme hills. So you are not going to spend a lot of time in the small ring. What you are going to use are the two big rings. If you are riding in hilly terrain, it is nice to have a middle ring that is low enough to let you climb moderate hills easily.

Pat

Now that I have no delusions of grandeur of staying at the front of the pack, I say the more gears, the better. I don't have to use granny, but it is noce to dump into should I feel the need. My current set-up is 53/39/28 with a 12/25. Seems to work great for me here in Maine with the hilly terrain.

Should I upgrade to 10 speed, I may consider one of the new compact road cranks. Dialing in a front deraileur on a triple with 10 speeds is a royal pain. I know because I have to deal with it on a regular basis here at the shop.

I've always had triples so it not a question for me.

My experiences are that you only use the bottom ring if you need it, and, why not have at least a one-to-one on hand for if you need it?

In one of your examples above, a 1:1 would be, e.g., a 28 ring with a cog to 28. I actually have a lower gear than 1:1 on both of my road bikes. Mtbs generally always have much lower gears than 1:1 and that is why many use mtbs for tours (even though you would put down many more miles on a properly set up road bike for the same amount of energy input).

Even the usual Shimano road cranks that are now made for optimum shifting properties in a post-friction shift era, the 30T bottom ring can be teamed with a cog to 32 (just thought I'd mention this because, it might not be obvious from the published specs: the 105/Ultegra specs indicate that these components--e.g., triple crank with a long cage dr--can only accomodate a max 27T cog).

... When riding the triple (52/42/30, 9-speed 12-25 cassette) I stay in the 42 most of the time just because I hate the feel of the granny gear, but do have to use it occassionally. The problem is that on those long gradual slopes the 42/23 or even 42/25 gets tiring and my cadence suffers. These are those hills that are a little too much for the 42 but not enough to justify the granny.

Conversly, when riding the double (53/39, 7-speed 12-28 cassette) the 39 works well for those same slopes, but, I run into the opposite problem where the 53 is just a little big and the 39 a little small for the flats.

For the double: Change the outer ring to a 48T so it's more like a double trekking crank, or just convert it to a trekking crank (48/38/28).

For the triple: Change the middle ring to a 39T and the outer to a 50T, or again just install a 48/38/28 ....

I don't know about you, but I would have absolutely no use whatsoever for a 53/12 gear, or even a 53/13. With your double, I would seriously consider something like 46-39 or the 47-38 combination I have been running on the Capo. (I currently use a 6-speed 13-15-17-19-21-23 freewheel, which provides too many redundancies, but your 7-speed 12-28 (12-14-16-18-21-24-28, I presume) should work out better.) I haven't checked this on a spreadsheet, but I suspect 48-38 / 12-14-16-18-21-24-28 works out pretty well.

For the triple, consider tightening the jumps to something like 50-42-34. The most satisfactory triple I ever ran was 48-45-34 / 13-15-17-19-21-23, but many of today's crank spiders preclude half-step gearing by placing the two outer chainrings too far apart, so that the chain falls in between or rides atop the middle ring's teeth.

A 50/34 compact combined with an 11-32 cassette would give you a gear range of 28 to 120 inches. There'd be a lot of duplication, so you wouldn't have to do a lot of shifting in front - just pick one and go.

I replaced the big ring on my double from 53 to a 50. I also changed rear cassette to a 12-27. This has given me the ability to stay on the 50 longer which I prefer but also helps when I need to drop to the 39 and go to the 27. Makes some of the rolling hills I ride a little easier.
Kenal0

For the triple: just install a 48/38/28. Any thoughts? Has anyone done something like this.
Yes.

It works great. The middle ring has enough bottom end to handle the long, gradual climbs, but there's also a granny to bail you out. The big ring spins out just at the point where I don't want to go any faster anyway.

Ring, a ring, bing!

I've decided that gearing (especially after reading these various posts), is about the same as saddle preference. No two riders are the same, no two bikes are the same, and no two hills are the same. Add all these variables together and each person has to adapt to the particular bike they riding and to the specific conditions the road throws down in front of them.

Tim, good luck in your quest!

My bike has a 50/39/30 and it works well for me.

I ride a triple, 53-42-30 front, 13-26 rear.

At first I reserved the granny gear for the 4 superlow gears I can't get on the 42. But lately, I've been switching to the granny when I know a long steady climb is ahead, even if I'm in the area where I'm overlapping the 42. In other words, I've been using my 30-18 and 30-17 which I never used before, and which are higher gears than 42-26.

This works for me, it preserves the nice tight ratios on the 42, it gives me range on the granny, and it lets me rip on long steady downhills because I still have the 53.

I have hills so when I got the Road bike I wanted a triple. 52/42/30 and a 12/26 rear cassette. I Mainly ride in the 42 and utilise all of the rear 8 sprockets. Chain line and Derailler rub comes in though so I use my loaf and if I want the 3 largest rear sprockets in the 42- I use the granny.

I know if I had looked a bit longer- I could have got a Compact crank with 50/34 but to me- a 34/26 is not as low as 30/26. Don't use that lowest gear very often but when I want it- I have it.

Just a point- Road bikes for roads and MTB's for the rough stuff but my MTB, did with a change of tyres, do a few road rides. Recently did a hill on the road bike and used 30/26. Managed it without breathing too hard- so why is it that when I last did it on the MTB- it was 22/32 or 30 and I struggled. If the lower gears are there- you will use them.

I like the 42 ring, and that's one of the advantages of a triple, in my opinion. The 39 just spins out too quickly before I'm ready for the 53. The 42 is just perfect.

Az

Just a thought to consider.

Even if the gear inches or forward travel per crank revolution is the same, it is easier to pedal on the smaller crank ring than a larger one. The leverage is greater on the smaller ring because of the smaller circumference. So, if you can achieve the same gear inches on the small chain ring and a smaller (higher speed) cog as you can on a middle ring/larger (low speed) cog, the pedaling will be easier and require less work on the small cog. Archimedes principle in action.

All that said, we tend to view the smaller chain ring as a last ditch weenie wonder when in fact it can make the ride easier.

The only caveat is if we cross chain too much.

As long as you are considering changing out the crank, I'd seriously look at a replacing your 52/39 with a compact double 50/34. With your 12-28, that's be plenty for the flats and the steep hills. I have a Shimano R700, 12-27 10sp, on my Merlin and it's sweet.

here's a question....on some of the changes being discussed here, wouldn't some of them require changes to the front and or back derailleurs?

Just a thought to consider.

Even if the gear inches or forward travel per crank revolution is the same, it is easier to pedal on the smaller crank ring than a larger one. The leverage is greater on the smaller ring because of the smaller circumference. So, if you can achieve the same gear inches on the small chain ring and a smaller (higher speed) cog as you can on a middle ring/larger (low speed) cog, the pedaling will be easier and require less work on the small cog. Archimedes principle in action.

All that said, we tend to view the smaller chain ring as a last ditch weenie wonder when in fact it can make the ride easier.

The only caveat is if we cross chain too much.

Assuming an equally straight chainline, the only difference between, say, 50/20 and 40/16 is that latter moves 20% less chain per crank revolution, which should be negligible if one's drivetrain is well-lubricated and properly adjusted. The chain will last longer with 50/20 than with 40/16, and the 20-tooth cog will last much longer than the 16. It would be interesting to quantify the difference in drive efficiency on a bicycle dynamometer (Frank Berto, where are you?), but I think it would be minuscule, worthwhile to a racer but not to an everyday cyclist.

Rings are cheap! Experiment with used ones off e-Bay all you want. When you find the right combo, sell your spares for what you paid for them.

It would be interesting to quantify the difference in drive efficiency on a bicycle dynamometer (Frank Berto, where are you?), but I think it would be minuscule, worthwhile to a racer but not to an everyday cyclist.

You're probably right, but the number crunching is fun for technoweenies.

I'm not one mind you, but I DO have an MSExcel spreadsheet matrix of all the gear-inch and actual inches traveled for all the gear combinations for all of my bikes, which can be quickly modified if I change tires. All I have to do is get out the centimeter tape and measure the wheel roll to judge circumference. Then measure it again to be sure...........convert to inches....plug in....check the forumulae again ..............

here's a question....on some of the changes being discussed here, wouldn't some of them require changes to the front and or back derailleurs?

If you are going to the MTB gearing of a large rear spread on the rear cassette (11/32) then some of the Road deraillers will not be able to cope. Front derailler should not need changing

I like the 42 ring, and that's one of the advantages of a triple, in my opinion. The 39 just spins out too quickly before I'm ready for the 53. The 42 is just perfect.

Az
+1

I am just the opposite, I currently have a 52/42/30 and would love to dump this for a 53/42 double. I never get down to the 30 and very rarely use the 42. Adjusting the FD on triple is also a pain and I prefer the shorter cage RD as well. Live and learn, my next bike will be a double for sure.

here's a question....on some of the changes being discussed here, wouldn't some of them require changes to the front and or back derailleurs?

When going from a standard 53/39 double to a 50/34 compact double, you have to lower the front derailleur a bit to compensate for the difference in diameter between the 53 and 50 chainrings. If you have a Shimano Ultegra/Dura-ace double and are switching to the Shimano R700 compact double, all the other drivetrain parts are compatible and you just have to lower the front derailleur.

I am just the opposite, I currently have a 52/42/30 and would love to dump this for a 53/42 double. I never get down to the 30 and very rarely use the 42. Adjusting the FD on triple is also a pain and I prefer the shorter cage RD as well. Live and learn, my next bike will be a double for sure.

Your next bike? Why not remove the 42 and 30 tooth chainrings, toss the FD, find a gently used short cage RD on ebay, and shorten the chain? Think of the weight you are saving! ;) If I lived in FL, I'd only use one chainring, but I'd probably go with a 49 or 50 tooth one (which would be an easy and inexpensive change to your crankset) but mount it where the smaller inner ring would go. This conversion shouldn't cost more than $40-60. Give it a whirl!

I could save more weight by removing the extra 20lbs I am carrying around my waist. I also don't think I would decrease my big ring since I am already getting down to the last few cogs on my cassette on occasion. I am always thinking about just upgrading my current bike vs buying something, but if I am really going to keep riding at the current rate I want to look at getting something special (bling bling). My only problem right now is that something special is a new roof for the house which is costing me a fortune.

I like the triple for the same reason you do. The 42 tooth middle ring is a good all round ring that I can use most of the time. I get a range from 8 mph or 25 mph on that ring and that pretty much covers it for me. The 30 is there for tough hills and the 52 is there for downhills or more aggressive flat riding. I find the 36 or 39 too low for anything but uphill riding. The small ring also allows me to climb with a higher cadence than a 39 and that's more efficient. The truth is most cyclists should use a triple but they are going out of style because the the compact cranksets.

My only problem right now is that something special is a new roof for the house which is costing me a fortune.

Polythene sheets and tarpaulins work for that. THERE IS NO CURE FOR A DELAY IN GETTING A NEW BIKE.

+ 1 : I can tell you that my own oft-cited, long-lamented 'wait until we can pay cash' servitude of having ONLY ONE BIKE is wearing thin, awfully thin so I'll second Stapfam's notion that the roof can wait, get that new bike! :D

Now I just need to change the password on our bank accounts & my MBA - (but still favorite) - wife won't be able to monitor my expenses so darn close...

Polythene sheets and tarpaulins work for that. THERE IS NO CURE FOR A DELAY IN GETTING A NEW BIKE.

I have had one of those in place since last Oct when Wilma did us in. My wife is getting tired of emptying the bucket in my daughters room. Getting trade work done these days is a whole nother story/thread. I have been told my current bike is good enough until we get someof the house stuff fixed and paid for. Reluctantly I agree, I don't need a new bike but I sure do want one.

I could save more weight by removing the extra 20lbs I am carrying around my waist.

Ha! Ha! Ha! I need to shave 40-50lbs off mine! (But at least it is not the 75 I had last year.)