Squeezebox

I'm thinking of a cassette specific for when i ride the Katy Trail, which I expect will be frequent, And other rail trails at times.
As many of you probably know my Trek 920 has 42-28 chainrings, and an 11-36 cassette. I bought a 12-28 cassette for day rides and the other times I don't that high or low. I'm thinking of taking the next step for a cassette specific for the Katy Trail. No hills, therefore less need for super low gears. Soft surface and no downhills therefore no need for real high gears. In the back of my brain is a memory of someone saying use a Jr. racing cassette for a lower high end. So I went looking for a cassette with a higher low and a lower high. I found a 15-25. (10 speed)
So with 2.0 tires
15-25
28/25 is a 32" gear, 70 RPM 6.5 mph
42/15 is a 80" gear, 90 rpm 21.5 mph

12-28
28/28 is a 28.5" gear, 70 rpm 6 mph
42/12 is a 100" gear, 90 rpm 27 mph

11-36
28/36 is a 22" gear, 70 rpm 4.6 mph
42/11 is a 109" gear, 90 rpm 30 mph

35 mm tires change things a bit, I cranked those #s forgot to print.
I went back to look at 42/13 which is 92" 25 mph. and 42/14 is 85.5" 23 mph. at 90 rpm.
For the Katy Trail I think the 15/25 would be a good choice. Have you ever gone over 22 mph on the Katy? With no hills , why would I want less than a 32" gear, and need less than 6 mph? I can plod through the soggy spots.
The bicycle is under 30 lbs, Gear and panniers 20-25 lb. It might be good.
I wish they made a 14-36 cassette for touring. I'm old enough I don't need to fast anymore. And maybe I just can't go fast anymore.

BigAura

Since you're in my age group I'd recommend:



But you're still using a Walkman???



Boombox not recommend since I remember you saying "let the lightness be with you"





So when you heading out on the trail?

mstateglfr 

Google says 2000' of climb over the 240mi of trail. So yeah thats pretty flat.

Get a 3rd cassette if you think it will help. Or dont, since thats overkill. Either way, go ride it.

BigAura

Ooops I think I misunderstood? For what I think you're asking I'll have to quote some sage advise:

JerrySTL

The Katy Trail is very flat from Machens to Boonville. However if you get off the trail to visit Hermann, Columbia, Jefferson City, and a few other places, you'll run into hills pretty quickly.

From Boonville to Clinton it is hilly. As it's a rails-to-trails, the grade is usually under 3%, but there are a few places where it hits 5%.

Personally I'd stick with the 12-28.

Squeezebox

In my early days I rode highway 94 from Jefferson City to Weldon Springs and back several times. Also from Columbia to Booneville more than a few times.
parts of it even more. For that I can't believe 2000 ft. but for Katy? No way!!

Jerry!
My experience is from Booneville to Weldon Springs. Jerry thanks a lot for your advice west of Booneville.

But since I'm a local the 15-25 might still not be stupid for the east of Booneville part. The cassette is only $50.

rm -rf

That's interesting. I'd never heard of a 15-25 10-speed cassette. It's probably for Junior racing, where their highest gear is limited by the rules, and is designed to work with larger chainrings. It's basically a "straight block" but with slower gears.

It doesn't seem to be a good fit for your 28 / 42 chainrings. I like close shifts to get to my preferred cadence, but these are extremely close together. You'd be shifting 2 or 3 cogs at a time.

See the chart attached, with the 28 chainring in red, and the 42 chainring in blue. I added a 34 chainring in black, just to see how it might substitute for the 28 on flat roads, but it won't work well here.

Here's the Mike Sherman gear calculator link for your setup. It tells you that you can bookmark / favorite those settings to save the setup. The charts update on the fly as you change cogs or cadences.

~~~~~~~~~

Your current 11-36 and 28 / 42 setup isn't optimal, but it would be able to climb some very steep hills.
Here's the calculator link.
See the 2nd chart below.

An 11-32 (which is 11-12-14-16-18-20-22-25-28-32) doesn't help either.

~~~~~~~~~~

I kind of like a 12-27 and 28 / 40, see the calculator link here.
(I couldn't find a 12-28 in 10-speed, but did see a 12-27 or 11-28.)
No really low gears, but a good range on the 28 chainring from 6 mph up to 15 mph. The 40 chainring covers 12 to 20 mph, with close shifts in the 15 to 20 mph range. And you can put your 11-36 back on for steeper rides.

~~~


Attachments: 15-25 with either 28, 34 or 42 chainrings. and 11-36 with 28 and 42 chainrings.

Doug64

I suspect that you will also need a shorter chain with the 25 tooth cassette than the one you are using with the 36 tooth cassette.

Squeezebox

your opinion of 25 vs 28 on the back? I did shorten from 36 to 28.

I will take a better look at specifics of the gear chart, and lay that out.
Still no reason to hate from some of the above.

Doug64

I'm not sure what you mean by your last sentence. All I did was give you my thought about chain length.

alan s 

Your current gears are fine. Take Shia's advice.

Squeezebox

Sorry! the comment was pointed at big aura not at you.

Still at $50 it will be an interesting experiment. Changing cassettes doesn't take long after the first few times.

BigAura

The Scientific Method

• Ask a Question.
• Do Background Research.
• Construct a Hypothesis.
• Test Your Hypothesis by Doing an Experiment.
• Analyze Your Data and Draw a Conclusion.
• Communicate Your Results.

You seem very adept at the first three steps. You need to complete the fourth step (which I've yet to see). The experiment is touring. Touring is what we are talking about right?

BigAura

It's not hate at all. It is:

cyn·i·cism

noun
1. an inclination to believe that people are motivated purely by self-interest.

synonyms: skepticism, disbelief

indyfabz

Is that Grandmaster Flash?

BigAura

yep

fietsbob

Katy, as a rail conversion, the grades are bound to be slight.

I understand its chipped limestone, not paved..

indyfabz

Using my masterful powers of deduction, I would have to say that the woman pictured with him is none other than Tina Weymouth. Correct?

indyfabz

Not always. From the official site of the Mickelson Trail:

"A majority of the trail does not exceed a 4% grade, but parts of the trail are considered strenuous. Dumont is the highest point and the 19 mile stretch from Deadwood to Dumont is the longest incline."

There are some very noticeable stretches of up hill, and I didn't even ride the Deadwood to Dumont section. Got on at Engelwood, the trailhead south of Dumont, and immediately started climbing for about 4.3 miles (at mile 30 of the profile):

https://ridewithgps.com/routes/8789073

That stretch averages about 2.75%. Throw in the soft trail surface and a headwind and it was not a simple thing.

With that said, I think the premise of this thread is inane, but it's his alleged money.

BigAura

Your are correct -> the image is titled: Tina Weymouth & Grandmaster Flash, 1981

Cool picture but I'm glad that we now have ear-buds/headphones and we can carry a personal music library that weighs almost nothing.

shipwreck

here is a link to the Katys elevation chart. Katy Trail Elevations

It is indeed really flat, with the only real hill being from Booneville to Pilot Grove. There is one more right before Rocheport that I have seen people flagging on while riding east to west.

I am confused. Did the OP do a ride or not? He alludes to experience from Weldon Spring to Booneville. If so, he has ridden it and should know what the hell gearing he wants and just do it. I hit 25+ mph on the katy often. its also nice to ride up the hills in Augusta, and up the little spur trail to Klondike state park.

Since every time I have ridden the trail it has been part of a longer trip with plenty of hills I use regular wide range gearing. If I ever ride it with friends, doing the trail only, I plan on riding a SA Three Speed hub bike.

MixedRider

Ride the trail with how the bike is. Tell everyone how it went. Post pictures and review your ride. What went well? What went bad? What would you do next time?

Fussing over a couple gear inches when you don't even really know what you want yet seems silly. If you use the max gear ratio and get 30mph+ let us know...

Squeezebox

I rode the paved road next to the Katy frequently before the Katy existed. There are some very steep climbs on that road between Jeff City and St. Charles. I've been on the Katy Trail a few times. It's not road bike friendly. Now I'm older and slower and ready for the Katy Trail. And I have the right bicycle, just thinking about tweeking the gearing.

robow

I agree with jerrystl, go with the 12-28 cassette. If you do decide you want to get off the trail,you'll appreciate the lower gears. Btw, don't listen to shipwrek, he's an animal, no mere mortal can peddle those classic vintage bikes at 25 plus mph on crushed limestone

shipwreck

You can if your on a road bike! Last time I did it was on 28mm tires. I did sink down once or twice, but the trail was fairly dry. I have a bad habit of not wanting to stop at a convenient campground in the afternoon, so then have to hammer it into dusk to get to the next town. Just put on some techno rave music and give it all Ive got. Helps me sleep at night