Trek FX 7.2 vs. Specialized Sirrus Sport
 

I did some bike commuting using Chicago's Divvy bikeshare system, and am now purchasing my first bike. My research has led me to two options: an on-sale Specialized Sirrus Sport ($525) vs. a Trek 7.2 FX ($490).

I realize these bikes are very similar, but I am nevertheless intent on making the "right" decision. So far as I understand it, the main differences are (a) the Trek has a steel fork and possibly better tires, but is otherwise a step-down on components; and (b) the Sirrus Sport has slightly better components, but an aluminum fork (less smooth ride) and possibly worse tires.

Am I missing something? What should I be thinking about? What would other people do?

I've thought this to death, so in an act of pure desperation from my own analysis paralysis, I'm turning to the internet for help. Thanks!

Regarding steel vs. aluminum fork: the material choice is only one piece of what contributes to ride quality, so you cannot make a blanket statement like aluminum = less smooth. After all, these bikes have aluminum frames. Have you ridden them? Go by what you feel, not what you heard.

That aside, if they're both within your budget, and both ride and fit similarly, go for the one better parts, or go for the one that is more attractive to you, or get the one is assembled better, or flip a coin.

Yeah, ride each if you can. Know that they are both good bikes and I don't think there is a wrong choice as long as you get one that fits.

Also remember that it's just a bike, not a marriage. ;) You're allowed to get a different bike if your heart starts to wander after a year or two and no one will think ill of you. You can even keep more than one at a time. There's more than a few forum members that are known to practice that form of polygamy.

Thanks for the feedback. I realize that fork material is just one piece of information, and I guess I thought others might be able to fill in the blanks. I've ridden both and did not notice much of a difference. Sounds like that means, as you say, I may as well flip a coin.

True. I guess I was hoping to stay monogamous for at least a little while with my first bike =-)

And you might.

As you've discovered, when you're starting out it's kind of hard to know what you really want. Everyone is a little different and not everyone's circumstances are the same. What may be the perfect bike for you might not make someone else as happy. Ultimately though there are lots of bikes that will get the job done. After riding for awhile, you'll figure out if you want something different or not. There's no way to know for sure without doing it for a bit.

If you told me that one had a decent carbon fork, I would very strongly say to go with that one. But steel vs aluminum...I mean the steel is a little better, but neither is carbon.

In my (albeit ancedotal) experience the whole bike can be aluminum just fine, but the fork being aluminum is not nearly as nice as the fork being decent carbon. The Trek FX doesn't seem to get a carbon fork until the 7.4 at $770 which is definitely more expensive.

Ride them both, choose whichever was more fun. Or had a nicer color.

P.S. Fit is the most important thing, so if one fits better go with that one. My assumption is that you can buy any size so there's not a difference.

Buying a good set of tires will have way more effect on ride quality than materials. I have owned steel, carbon, and aluminum bikes and most of the ride quality crap you read on here is just people who overinflate their tires.

Don't flip a coin. If you like them equally well after test riding each, save yourself $35 and buy the cheaper one. Put the $35 towards a good lock.

Frame geometry influences ride characteristics a lot more than the material.
Tubing diameters and design influence ride characteristics a lot more than the material.
Carbon is the best in terms of allowing producers to make ride characteristics exactly as they plan, but they don't always put the effort to make use of that opportunity, not on cheaper frames that come with bikes under 1000$. The same goes for metal frames in lower price category.


Tyre width influences ride comfort a lot more than frame material, frame geometry and tubing design.
Tyre quality influences ride comfort almost as much as tyre width does. This means a subtle, quality tyre will provide a more comfortable ride than a wider, but poor quality tyre. Of course, wide + high quality is even more comfortable.


Choose a bike that you like best when test riding.

If you don't have eyeballs on your bike at either end of your commute, don't buy a new bike. Plenty of good used bikes in Chicago. No lock will defeat $40 worth of cordless tools.

If the secure storage issue is solved and iF a bike is your only means of transit, other than public, don't skimp too much.

I looked at the Sirrus Sport specs and don't find the Altus/Acera rear derailleurs compelling.

As far as the Trek FX line, I think the $200 up charge for the 7.3 is worthwhile for a more robust component group. Also, when time comes to let go of the bike voluntarily, you'll get at least half the upcharge back.

I was in the exact same position as you a few months ago. Here’s the deal: Both bikes are gonna be really nice and are of similar quality, and chances are you won’t be able to discern much of a difference when you ride them. That being said, just go with your gut and your heart and choose the one that you like best. You’re going to love the one you get, so it’s really not going to matter in the end which one you choose. I went with the Sirrus. That’s nothing against the Trek, I just liked everything about the Sirrus – the ride, the colors (matte black with blue accents), I liked the guys at the LBS that sells Specialized, etc.


One recommendation I have for you is to pay an extra $100 or whatever to get a model with disc brakes. I got the Sirrus Sport Disc model, and the disc brakes are awesome – 100% reliable in the rain (and you WILL ride in the rain at some point) and they are so easy to operate – you can literally squeeze the brakes with your pinky finger and stop on a dime. I’ve had the bike for a month and I can already say I’ll never go back to non-disc brakes again.


Anyway, stop agonizing and just pick the one that strikes you the best.

I agree with a lot of what you wrote, except the bolded part.
I went from a all aluminum touring bike (including the fork) with 35c tires, to a well designed aluminum + carbon front fork road bike with 25c tires, and the bike with smaller tires is actually far more comfortable in eliminating road buzz as I ride. Despite the smaller tire size it's actually more comfortable in handling the lip where sidewalks dip down but don't quite come all the way down (there are a few small stretches where it would be illegal / insane to ride on the road and the sidewalk is built for bikes to get between more rideable sections for me).

It's ancedotal, but in my experience a decent carbon fork has always been worth the cost vs an aluminum/steel one, whereas a full carbon frame often is not worth the increase in cost depending on your finances. I have to go to a larger tire than 35c to get the benefits a carbon fork would otherwise get me. Again, in my experience.

My experience has been the opposite.

You went from a modern aluminum bike with a carbon front fork, to an older aluminum bike with an aluminum front fork?

I'd get the Trek, in blue, because I like the color.

Well, actually, I did. :)
But what I meant was the tyres influence compared to frame & fork influence. But I did experiment with all sorts of frames (steel, alu-carbon, road, MTB, touring geometries...).

Important factor is also tyre quality. Good 28 mm tyre was softer than a heavier, lower quality 37mm one. But with same tyre quality, jumping from 23 to 28mm for example adds a lot more cushioning, than swapping alu with a carbon fork - in my experience.

One of the problems is that we end up debating two different terms.

One set of issues is caused by bumps or cracks in the road, road surface (smooth asphalt, that slightly bumpy stuff, crushed limestone, dirt roads, etc). I could certainly believe that had I used a higher quality 35c tire things might have come out differently. Those issues are usually solved with a wider tire.

A different set of issues is road "buzz" where vibration travels from the road up to your hand. This is what a well designed well shaped bike frame handles much better than changing tire size in my opinion. You might be able to get rid of with a **much** wider tire, but a carbon fork together with a better designed aluminum bike worked much better for this for me.

Eventually on a forum you collect every possible opinion lol, but for road "buzz" not "bumps" I haven't found wider tires to be helpful unless they're way wider.

I agree with everything above. For what it's worth, I was in the same predicament as you, and I decided to go with the Sirrus, based on appearance, brand perception, LBS

As a fellow Chicago commuter the most important thing you need for a new bike is a high end lock. I use to park downtown and used a Kryptonite NYC U-lock and On Guard mini lock for the front. Bike theft is extreme in Chicago and Summer is prime season.

Like I said, my experience has been the opposite. Carbon fork, alu fork, steel fork - all felt more - less the same with harder, narrower tyres, while good quality tyres, wider than 25 mm turned out to be the winning combination.

Laying aside fit...
 

...the next most important thing is tire selection when considering ride quality. Not only width, but tread/sidewall characteristics and riding the right pressure (i.e., not too inflated).

And BTW, how many bikes have aluminum forks? I'm really surprised to hear that... I know that Vitus has one with troubles a few years (decades) back, but I'm not sure I've seen an aluminum fork on any bike. And I've handled hundreds...

You skipped around what said about debating different terms. Dunno what else to add, 25c tires on a well designed aluminum bike definitely had a better ride for road buzz than 35c tires on an all aluminum touring bike for me. Guess it's a forum and we have different opinions.


I was kind of surprised to find it easy to find if you look at low end hybrid bikes. Like a Trek FX doesn't get a carbon fork until around $700.

BMC has an aluminium fork on some of their "hybrids".

Cannondales had several varieties of aluminum forks, "Pepperoni" with curved legs and "P-Bone" with straight legs. The Pepperoni on my XR800 flexed in tune with the brake chatter before I had them adjusted properly, and it's kind of frightening to watch how far it can flex. Nevertheless, the ride is stiff.