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Ellen 06
08-14-2006, 01:22 PM
I'm planning to ride a metric in two weeks. Saturday I spent the morning doing loops and went 59 1 /2 miles, 15 further than my previous furthest distance. Next week I'll follow the actual route with the hills.

I'm doing this on my 7 speed elektra Townie. I love this bike, but I think it might be time to start looking for a new bike. The only problem I have with it, is I should have bought a 21 speed. I've put over 820 miles on it in just 3 1/2 months.

But, my top speed with this bike is about 17 mph if I really push and pant, and my average speed is closer to 13 or 14.
My biking friends are blaming this on my fat-tired bike. I'm blaming it on my fat, tired body. I'm not convinced that a thinner tire is going to make that much difference. Is it?

My LBS has some ideas for bikes for me to try. AT the moment I'm most inclined to the 27 inch, 21 gear townie model with thinner tires, but I will give the road bike models they suggest a try.

The upright posture is practically essential, because my right wrist will not stand certain positions, whether there is any weight on it or not. Even with a higher stem for handlebars I'm afraid I'm going to have a problem with a road bike because of the geometry of the seat and pedals would still throw me forward onto the wrist.

Ellen

mimitabby
08-14-2006, 01:27 PM
There was an article recently that pointed out that your money is better spent on aerodynamic helmets than it is on skinnier tires/wheels. It also said that
it is more aerodynamic to have your water bottle cage on the seat upright tube
instead of the angled tubes.
Lastly, and least useful was that gloves create a lot of aero resistance.

I just reread your question; sorry. A different kind of bike will surely increase your speed.
maybe one of the lighter hybrid bikes? like the top of the line Raleigh hybrid (look mine is for sale in the for sale part here) :D


Mimi

Veronica
08-14-2006, 01:27 PM
Speed wise - a narrower tire will have less rolling resistance and you will be able to go faster.

Narrower tires are less cushy, so you will get a rougher ride.

V.

Veronica
08-14-2006, 01:35 PM
http://www.hsbikes.com/images/elektra/elek94.jpg

Is this your bike Ellen?

Having more gears will make your riding a bit easier. And I would suggest trying every bike that your LBS has, even mountain bikes, given that you want a more upright posture. You never know what may end up being comfortable to you.

V.

SadieKate
08-14-2006, 01:45 PM
Ellen, dramatic differences in tire width do produce a dramatic difference in speed. Most of the time we're discussing the difference between a 23 and a 25 mm tire in which case it's pretty neglible. The tire construction and inflation can make the difference with such a small variance, not the tire width.

However, if you are comparing a "fat tired" bike to a road bike with 23 or 25 tires, you will find that the narrow tires have significantly less rolling resistance and require less effort to maintain or achieve more speed. Depending on your terrain and your ride goals, you may want to look into recumbents. The position on the bike is more aero dynamic than the townie but recumbents, just like diamond frame bikes, have their pros and cons.

xeney
08-14-2006, 01:49 PM
There was an article recently that pointed out that your money is better spent on aerodynamic helmets than it is on skinnier tires/wheels.

But are they talking about differences in road tire widths (like 23s versus 25s) or are they talking about more significant differences, as between cruiser or mountain bike style fat tires and pretty much any road bike?

I have slightly fatter tires on the two road bikes I use for commuting and transportation than I do on the one that I just use for fun, and I'm not sure that any of the speed differences among those bikes can really be attributed to the width of the tires. But I can go much, much faster on my commute bike - a steel mixte weighed down with metal racks and baskets, and the most un-aerodynamic stem and handlebars you've ever seen -- than I can on my mountain bike, and I am sure it is because the mixte has skinny road tires. (They aren't even all that skinny for a road bike.) Switching from a hybrid to a road bike raised my average speed by about five miles an hour immediately, and I was wearing the same gloves and helmet.

SadieKate
08-14-2006, 01:51 PM
The helmet/tire comment is probably from the Bicycling Magazine article on the MIT cycling team and their studies of aerodynamics in a wind tunnel using road and time trial bikes.

mimitabby
08-14-2006, 02:13 PM
But are they talking about differences in road tire widths (like 23s versus 25s) or are they talking about more significant differences, as between cruiser or mountain bike style fat tires and pretty much any road bike?

Yes, they are talking about the miniscule differences between a 100 dollar wheel set and a 400 dollar wheel set. As I said in the second half of my post,
I could see this was not the issue here.
I went from a higher end hybrid to a midrange road bike and there was a BIG BIG difference. and if that bike is ANYTHING like my worksman bike at work
http://www.bikejournal.com/images/mimitabbyfuschiabike.jpg

she's going to just FLY on something like my Raleigh c700

Geonz
08-14-2006, 02:29 PM
FOr the purposes of this situation, that article is RONG. (I know, that's wrong ;-))
WHen I went from 35 cm tires to 28cm, I *instantly* got 2 mph. Same body. YOu've probably got 38cm tires.
It's physics. Watch how often others are coasting while you are pedaling. They are not "stronger" sitting there gliding! Your bike is slowing you down. Hey, if you need reasons to berate yourself ("my fat tired body" - okay, it was cute :) ) I am sure you will be able to find them... it won't make you an instant racer - but it will, simply, make riding easier. People will say "oh, another person who got a comfortable bike and then started racking up the miles!" It's a fairly common modification ('cause tires are a whole lot cheaper than bikes).
THe other things to do are get them tires all inflated (the smaller ones will prob'ly take more pressure), and lube that chain, and make sure the brakes aren't rubbing... and you'll be amazed. You'll be comin' back shoutin' and singin', it'll be so much fun.

mimitabby
08-14-2006, 02:38 PM
yeah, now that i am finally getting used to riding my road bike my DH says to me; "And you can use your hybrid bike for your commute"
NO WAY!! I LIKE going uphill on my light little road bike!! It's made a world of a difference.

If I had a flat commute, it might be different. He thinks I should have different bikes for different purposes, but really, i like riding just one.

xeney
08-14-2006, 03:29 PM
I like having multiple bikes, but I wouldn't have another fat-tired commute/city bike. I whine enough about the fat tires on my mountain bike, and on the rare occasion when I have to ride it on pavement, I bellyache the whole time.

Veronica
08-14-2006, 03:40 PM
I like having multiple bikes, but I wouldn't have another fat-tired commute/city bike. I whine enough about the fat tires on my mountain bike, and on the rare occasion when I have to ride it on pavement, I bellyache the whole time.

That's funny - I find riding my MB on pavement kind of freeing. It's okay that I'm slower... I'm on my MB. :D

V.

Kano
08-14-2006, 07:39 PM
Oh! Oh! Oh! I love my thinner tires!

A few months ago I bought a Specialized Expedition Sport "comfort bike" --- knobby, 2 inch wide tires on it. My average speed, on flats, was 10mph at best.

I got the new tires, 1 1/2 inch wide, smooth tires, with tread that reminds me of worm-wood on them. My average speed now is 11.7mph. BUT that's because now I go on hills, and those 30+mph descents just don't fix a 4mph uphill climb... Most of the time, when I'm on uncrowded flats, I tend to run around 14-15mph now.

Granted, I'm stronger than I used to be, but those tires made an instant difference. It's not just speed, but my endurance is better too -- I can ride farther than I did with the knobby tires too! -- DH believes in "my bike ladies" now and is truly afraid of you all!! (it's the effect on his wife that scares him most!)

Karen in Boise

DDH
08-14-2006, 08:17 PM
I ride my MB on the road all the time. I'm not in any shape to go off roading anymore and the MB is all I have. My DH has put smoother tires on my bike to help the resistance since I don't ride much off road, but they are still also big enough that I can ride off road some without worrying about getting an instant flat. My avg speed right now is anywhere from 10 to 11, but I ride a lot of hills out here where I live and dont' expect a lot of speed. I am more interested in getting fit and losing weight anyway though.

Trek420
08-14-2006, 09:32 PM
Ellen 06 "I've put over 820 miles on it in just 3 1/2 months."

you da woman! :D

Do thinner tires make a difference? Yes! Before AIDS Lifecycle 4 I took my bike in to get new tires. I think I was using 26s.

My LBS said they were out of them (I think Chris just said that to get me skinnier tires) "so we'll give you a set of 25s since we don't have what you want"

Does 1mm make a difference? I felt like I flew on the other hand very sketchy and skiped sideways in crosswinds and turns. Took a little getting used to but once I did I'll never add the mm.

KnottedYet
08-14-2006, 10:15 PM
I think I have 38's or 35's on my commutermobile. Tried out a Jamis Aurora with 28's.

Wheeeeeeeeeee!

A whole lot faster, and not so narrow that I felt insecure.

Kalidurga
08-15-2006, 06:10 AM
There was an article recently that pointed out that your money is better spent on aerodynamic helmets than it is on skinnier tires/wheels. It also said that
it is more aerodynamic to have your water bottle cage on the seat upright tube
instead of the angled tubes.
Lastly, and least useful was that gloves create a lot of aero resistance.


FOr the purposes of this situation, that article is RONG. (I know, that's wrong ;-))

That article was in a recent issue of Bicycling magazine. They were specifically talking about time trialing, though, so the guys who did the study were into minutiae way beyond the question in this thread. Interesting stuff, though: Revenge of the Nerds (http://www.bicycling.com/article/0,6610,s1-3-12-14995-1,00.html).

I've been thinking of getting another set of tires for my 'cross bike. It came with 32's that have just a bit of tread, but I'm thinking about maybe getting something a bit knobbier for when I know I'll be riding in sand, gravel or mud. Or, I could go the other way and get slightly thinner and smoother tires to go faster on pavement... Hrmmm... How long is it till Christmas? :rolleyes:

RedRansV2
08-19-2006, 11:26 AM
Ellen,

820 miles in 3.5 months, with an average speed of 13-14 mph, on a 7 speed Townie??!! You rock, woman!

With that kind of commitment and ability, you deserve and would truly appreciate, a more performance oriented bike. You've recieved some good advice about tires from people who have more experience than I do. What I do know about is trying to find a bike I won't outgrow when my choices are limited by hand and wrist pain.

After you've completed your metric, and are looking around for a new bike, take a look at www.ransbikes.com. Their Crank Forward series, the first 5 bikes in the pictures, is designed to provide more performace while still taking pressure off the hands and wrists. As you can see from the pictures, Rans, is primarily as recumbent bike manufacturer. They've been in business a long time and have an outstanding reputation. (I ride their Velocity 2.) Like all recumbent companies, they have a tiny distribution network compared to companies like Trek and Cannondale so I don't know if there's a dealer in your area. I've ridden the Fusion and it was FUN, but I was intrigued by the bents and got one of those instead. But I'm thinking that I need to add either a Fusion or Cruz because...I don't know, they're just different. At 5'2", I'm too short for the Zenetik or the Dynamik. There's a good discussion Board for Crank Forwards over at www.bentrideronline.com. Go to Message Board>Specialty Discussions.

I'd recently read that Rans was offering a "Satisfaction Guaranteed" deal whereby you could try any Crank Forward for 30 days and recieve a 90% refund if you returned it in good condition. So I called Rans on Thursday and recieved a call back on Friday verifying that that was accurate info. Hmmm

Oh BTW, all the hype about how well they climb is aimed at the bent crowd, those of us happily riding around on 35 lb bikes. This is not some magic climbing machine. It climbs a heckuva lot better than a Townie, but it's not like standing on the pedals of a sub 20 lb road bike. Oh yeah, all these bikes use standard bike components, like you'd find on any diamond frame.

Anyway, Veronica's right; try everything at your LBS, because you never know what you'll wind up with. Have fun on your metric, Ellen and let us know how it went!

RoadRaven
08-19-2006, 12:44 PM
Yup. I'm gonna join the voices of the others here, saying: They make a difference

The bigger the tyre, the heavier it is - therefore the more weight you have to push/drag along with you.

The wider or knobblier the tyre, the more friction you have to fight, the more drag resistence on the road you have to work against.

Yes, tyre width and slickness definately will make a difference to your speed.


NB: I think the articles around spending money on aero bars and bike helmets are written with the assumption that you are beginnning with a road bike - not a mountain bike or a hybrid/comfort bike. Therefore those articles would see aero bars and helmets and wheels as the next step, because they will be assuming the bike already has slicks on it.

Saxa82
08-20-2006, 05:02 PM
I ride a mtn bike that I "souped up" for the road, meaning I put smooth tires on it. Instantly gave me 2 mph advantage. I definitely recommend putting smooth tires on the bike, since that's the easiest way to gain speed with your type of bike. With a hybrid (or mtn bike) you're already upright, so you lose a lot of aerodynamics with the position. Being upright is the biggest detriment to higher avg speed, but if you are more comfortable being upright, then that's more important to you than going faster. If going faster was your top concern, then you'd have a light road bike. So it's all a matter of preference. I, for one, prefer the comfort of a mountain bike, mine is light and has loads of gears for the crazy hills we have here. The best way for me to increase speed was to put the slicks on.