Clydesdales/Athenas (200+ lb / 91+ kg) - What's the point of my triple chainring?

My Trek 520 has a 9 speed 11-32 cassette and a 50-39-30 chainring. According to Sheldon Brown's calculator, I get the following gear ratios (in meters of development):

Chainring High Low
-------------------------------
50 9.7 3.3
39 7.6 2.6
30 5.8 2.0

That 3rd lowest chainring gives me a 2.0 and 2.3 meters-of-dev gearing, which is just barely under the lowest gears on the 39 tooth. What's the point? I've found getting in and out of the 30 to be a little tough too. As the hills get easier I find myself rarely shifting to it, if ever. This seems like a needless complication of the drivetrain, I wonder why Trek chose this chainring set.

Perhaps when I eventually need to replace some parts I'll just convert the front to a pair like 50/34 and call it good.

Your 520 was built to be a loaded tourer. Imagine climbing a mountain pass with 6K plus in elevation change with 70 lbs of gear, your bike, and you.

If you are never going to tour, or climb that kind of elevation, then it is probably overkill.

Enjoy your 520, they are very nice bikes and a touring classic.

Your 520 was built to be a loaded tourer. Imagine climbing a mountain pass with 6K plus in elevation change with 70 lbs of gear, your bike, and you.

If you are never going to tour, or climb that kind of elevation, then it is probably overkill.

Enjoy your 520, they are very nice bikes and a touring classic.

I understand the whole crossing-the-Continental-Divide thing, but wouldn't that call for a much smaller 3rd ring, like a 24 tooth or something, to be really useful? The Surly LHT uses 48-36-26 with a 11-34 cassette, which seems much more useful for heavy loads and steep ascents. The 520 gearing just seems a bit odd to me, I guess.

In any case, I do like the bike quite a bit. I'm starting to think the frame might be a wee big for me but that's a thought I will re-visit in a year or so when ye olde budget allows it.

I understand the whole crossing-the-Continental-Divide thing, but wouldn't that call for a much smaller 3rd ring, like a 24 tooth or something, to be really useful? The Surly LHT uses 48-36-26 with a 11-34 cassette, which seems much more useful for heavy loads and steep ascents. The 520 gearing just seems a bit odd to me, I guess.

In any case, I do like the bike quite a bit. I'm starting to think the frame might be a wee big for me but that's a thought I will re-visit in a year or so when ye olde budget allows it.

Changed my 30T to a 24T. Now I can climb like a goat.

I only understand gear inches.

I believe a 30T ring is the smallest that fits on a road triple with its 130MM BCD.
IF you want smaller rings, you need a mountain crank with 110MM BCD.

Why not change your cassette to something like an 11/12-23/25/27? That would give you more closely spaced gears for cruising.

Although the case you state isn't that good, you don't want to be in the position that you have to make double shifts back and forth either. Think of them as "ranges", and also avoid cross chaining.
S gears 1-6
M gears 3-7ish
L gears 4-9

9 teeth on the front chainring makes more of a difference then you think. It seems like the same thing and unecessary until you are going up a 15% grade or carrying 100lbs extra.

That's a racing triple set up you have, not a touring one. This is why you might question the need for it. I have one too on my road bike. I'm not a clydesdale, but I'm in my mid-50's, plus I have some medical limitations. So those are MY excuses :-)

I never use the 30 inner ring for any normal riding over rolling terrain, but it comes in very handy when I need to go up a steep incline (there are often many opportunities for those in cities, short but very steep sections of street or laneways). Sometimes the 30 ring allows me to choose routes that have some of those on purpose. It's not only easier to climb it, but it's also easier on my knees.

I think that a compact double can be a working substitute for a racing triple, but absolutely not for a touring triple (smaller inner ring than on a racing triple). Personally, if I changed anything, I would change to a touring triple rather than go to a compact double. But if you don't need that, and you can't leave well enough alone, then a compact double could be an option.

One of the complaints about the 520 for touring (according to the touring forum) is that it doesn't have low enough gearing, and many tourers change the crank.

But the bottom line for a road triple is that the drop from a 39 to a 30 may not be a lot, but if you need it, any little bit helps. :)

By the way, I use a compact double myself...

I understand the whole crossing-the-Continental-Divide thing, but wouldn't that call for a much smaller 3rd ring, like a 24 tooth or something, to be really useful? The Surly LHT uses 48-36-26 with a 11-34 cassette, which seems much more useful for heavy loads and steep ascents. The 520 gearing just seems a bit odd to me, I guess.

In any case, I do like the bike quite a bit. I'm starting to think the frame might be a wee big for me but that's a thought I will re-visit in a year or so when ye olde budget allows it.

You are not the only one who sees the 520 gearing as odd. It's an old complaint about the 520 that Trek has never addressed.

For most experienced tourists (at least the old ones with marginally functioning knees:rolleyes:), even the LHT is gear high. I run a 46/34/22 on my touring bike. It came in handy on this part of the Lewis and Clark

http://i144.photobucket.com/albums/r181/cyccommute/Hotandsteep7_1.jpg

Alpowa Summit. 700feet to 2700 feet in 12 miles with only a single shade tree on the entire 103 F ride:eek:

I have similar gearing on my Jamis Quest, although the cassette is something like 12-23. As has already been said, I don't use the 3rd ring on rolling hills, but when a hill becomes more than rolling, or even a long, but not too steep incline, I use the third ring. I prefer this over the gearing of a compact double because the gap between the rings is smaller, which means easier shifting between them. It also allows me to run a tighter range on the cassette, which makes it easier to stay at a target cadence. If you're having trouble shifting in and out of the 30, perhaps a bit of adjustment is in order, mine shifts well between the rings.

What's the point?

How far are you riding? After doing 50-60 miles of rolling to moderate hills, I find that the lower gearing offered by the inner chain ring looks much more attractive than it might at first glance... :D

My Trek 520 has a 9 speed 11-32 cassette and a 50-39-30 chainring. According to Sheldon Brown's calculator, I get the following gear ratios (in meters of development):

Chainring High Low
-------------------------------
50 9.7 3.3
39 7.6 2.6
30 5.8 2.0

That 3rd lowest chainring gives me a 2.0 and 2.3 meters-of-dev gearing, which is just barely under the lowest gears on the 39 tooth. What's the point? I've found getting in and out of the 30 to be a little tough too. As the hills get easier I find myself rarely shifting to it, if ever. This seems like a needless complication of the drivetrain, I wonder why Trek chose this chainring set.

Perhaps when I eventually need to replace some parts I'll just convert the front to a pair like 50/34 and call it good.

I don't understand why you think a 30% difference is insignificant. That's about the same as changing your 32 cog in back to a 25. Not significant? Then why are you using a cassette with those HUGE gaps?

To make a better (IMHO) riding system:

- Dump the 11-32 and get something without those gaps. If you currently really are comfortable with the 39/32, then go for a 12-25 cassette.

- Keep the triple and tune it so that it shifts correctly. There is no reason that it shouldn't shift just a well as a compact double.

TF

I believe a 30T ring is the smallest that fits on a road triple with its 130MM BCD.
IF you want smaller rings, you need a mountain crank with 110MM BCD.

The 30t ring on a road triple is on a 74mm BCD (IIRC). A 34t ring is the smallest you can go with a 110mm BCD.
The factor which limits the setup to a 30t inner ring isn't the BCD, but rather the front derailleur capacity. You've typically got a 20t or 22t total capacity between the inner and outer rings, so a 50t outer ring will limit you to a 30t inner ring (but a more common stock setup is a 30t inner and a 52t outer.)

I believe a 30T ring is the smallest that fits on a road triple with its 130MM BCD. IF you want smaller rings, you need a mountain crank with 110MM BCD.

My tourer has a Deore drive train. I'm not going to win any sprints when on the big ring, but that third ring let's me spin for days. I find myself spending most of time on the middle ring and big rings though.

I'm going to be putting a 105 racing triple on my Cannondale soon, and might make the jump from 8 spd to 9 spd since I just got a good deal on an Ultegra RD that has a nice long cage. The difference in ring size between the Deore and 105 is huge. The brifter change is my only hold up on jumping from 8 to 9 spd.

My tourer has a Deore drive train. I'm not going to win any sprints when on the big ring, but that third ring let's me spin for days. I find myself spending most of time on the middle ring and big rings though.

I'm going to be putting a 105 racing triple on my Cannondale soon, and might make the jump from 8 spd to 9 spd since I just got a good deal on an Ultegra RD that has a nice long cage. The difference in ring size between the Deore and 105 is huge. The brifter change is my only hold up on jumping from 8 to 9 spd.

You don't have to use a 9 speed derailer with a 9 speed system. The derailer is a robot and will do what ever the shifters tell it to. There's a lot of expense involved in changing from one speed to the next with very little benefit. An 8 speed system isn't that much different from a 9 speed nor, for that matter, from a 10 speed.

Hi - just spotted this thread.

I have a Trek 520, too. Like many owners, the first thing I did when I got it was change the crankset. I bought a Shimano Deore LX triple -- I think the chainrings are 46/36/22 . A couple of big advantages:

- I now have a couple of super lower gears. I *don't* walk up hills.
- The 36- and 46-tooth chainrings are both really practical for around town. I use all 3 chainrings on almost every ride (I climb up a 12% grade every time I leave my driveway).

And, no, I don't miss having a 52tbig chainring on this bike. Pedalling at 105 rpm in top gear I'm doing over 25 mph. On a bike this heavy you won't see me going that fast very often...

Really, I would like to say "to each his own," but IMHO the stock gearing on the 520 is *absurd.* It's a tank-like, ultra-steady touring bike that loves to carry a load. It should have gearing that reflects that, which is why I changed mine. Once you have a really low-geared triple you'll appreciate them even more.

(BTW, this was not an expensive change -- I bought a new crankset on eBay, sold the old one on eBay...net cost to me was about $50).

http://i37.tinypic.com/e0g477.jpg

You don't have to use a 9 speed derailer with a 9 speed system. The derailer is a robot and will do what ever the shifters tell it to. There's a lot of expense involved in changing from one speed to the next with very little benefit. An 8 speed system isn't that much different from a 9 speed nor, for that matter, from a 10 speed.

If you have an indexed shifter, then there is QUITE the difference.

If you have an indexed shifter, then there is QUITE the difference.

An derailer is a derailer. It doesn't care if the shifter tied to it is a 7, 8, 9 or 10 speed. In fact many derailers are sold as 7-8-9-10 spd derailer. The shifter makes a difference but the derailer does what it is told.

And, of course, I'm talking about indexed systems since those are on 99.9999% of the bikes out there.

Ah. I had assumed that you meant cassette with dérailleur. In that case yes, it doesn't matter. If there is a cassette change though, an 8 spd shifter will not work properly with a 9/10 speed cassette.

You don't have to use a 9 speed derailer with a 9 speed system. The derailer is a robot and will do what ever the shifters tell it to. There's a lot of expense involved in changing from one speed to the next with very little benefit. An 8 speed system isn't that much different from a 9 speed nor, for that matter, from a 10 speed.

I think you missed the part about the Ultegra has a nice long cage for using the triple in addition to making the jump to 9 speed. I realize that any dr capable of an 8sp casette will shift 9, but a short cage doesn't handle a triple as well.

As far as going to a 9, it's just something that I want to do eventually. The brifter is the hold up, although I really only need a right side to do it.

I think you missed the part about the Ultegra has a nice long cage for using the triple in addition to making the jump to 9 speed. I realize that any dr capable of an 8sp casette will shift 9, but a short cage doesn't handle a triple as well.

As far as going to a 9, it's just something that I want to do eventually. The brifter is the hold up, although I really only need a right side to do it.

I didn't miss that part. Going from an 8 to a 9 speed on a bike is an expensive proposition for little gain. A 105 STI set will cost you around $220, a cassette will cost you around $60, a new front derailer will cost you around $40, new tape (you'll have to move the levers off) ~$20, new crank around $200 for Hollowtech II (or around $50 for Octalink), plus what the derailer cost...say $70. That's between $425 to $575 to gain one gear on the back that is shoe horned in between an already tight cluster anyway.

Before you spend that kind of scratch, you might what to look at a couple of cheaper options. Are your current shifters only for a double or will they handle a triple? Even if they are only a double, these guys (http://www.icyclesusa.com/catalog/shimano/left-shimano-105-st-5510-9-speed-sti-lever.htm)sell the left shifter/brake unit for $80. You'll still need a crank, front derailer and bar tape but that saves you $200 right there. If you want a triple 105 octalink PM me.

I didn't miss that part. Going from an 8 to a 9 speed on a bike is an expensive proposition for little gain. A 105 STI set will cost you around $220, a cassette will cost you around $60, a new front derailer will cost you around $40, new tape (you'll have to move the levers off) ~$20, new crank around $200 for Hollowtech II (or around $50 for Octalink), plus what the derailer cost...say $70. That's between $425 to $575 to gain one gear on the back that is shoe horned in between an already tight cluster anyway.

Before you spend that kind of scratch, you might what to look at a couple of cheaper options. Are your current shifters only for a double or will they handle a triple? Even if they are only a double, these guys (http://www.icyclesusa.com/catalog/shimano/left-shimano-105-st-5510-9-speed-sti-lever.htm)sell the left shifter/brake unit for $80. You'll still need a crank, front derailer and bar tape but that saves you $200 right there. If you want a triple 105 octalink PM me.

Agreed, if I had to buy all that stuff it would not be worth it.

I have everything I need except the cassette, narrow 9 sp chain, and right brifter. The point about only gaining one gear is valid, however. Perhaps I should just go for 10sp and gain two!:D

I'd keep that 8 speed setup just for the chain wear issues on a touring bike with the little 9/10 speed chains.I get twice the life out of a 6/7/8 speed chain as my buddy does on does on 9 speed chains.