I'm looking for an all purpose commuter, fitness bike, just have fun on bike. I went to the local shop and they have both the DS's and the FX's. I know the DS is more of a mountain bike based bike while the FX is street focused. I like the idea of the wider tires on the DS and the suspension. But I'd probably be more on the road, since any real trails will need a serious mountain bike and not the FX.

I like the 7.7FX because of the carbon frame but the sales lady told me that you couldn't put wider tires on it where the 7.6 had some more flexibility and you could put a wider range of stuff on it. So I'm pretty torn between the 7.7 and 7.6FX and an 8.6DS. What do you guys think?

Can't really say much about the 7.7FX, except for the fact that CF can be a real PITA, in terms of caution about scratching it, locking it up on metal racks next to beater bike owners, who couldn't give a rats behind about scratching your bike up to free theirs. Then there's the where-do-I-lock-my-bike-up-around-here syndrome. There's usually no kick stand and you have to be weary about laying it down some random place. You don't wanna lean it up against anything for fear that it will either get scratched up or it will fall down. If you crash on it, you'll have eternal worries about its structural integrity, forever!

The hybrid DS bikes are just hybrids that are made to do the same thing that any other hybrid can do, except that they carry more weight, due to their suspended forks. If you have some kinda medical condition, then a DS hybrid should serve you well, because they'll better cushion road vibrations and will help to stabilize your bike, should you misjudge your line. Otherwise, a rigid forked hybrid will be more efficient and most likely, more enjoyable as well, with regards to speed.

Therefore, your answer is, IMHO, choose the 7.6FX!

I love the nimble, quick feeling of my FX, and the ease with which it attains and maintains speed. I would not want to compromise any of that even a little bit.

80% of my riding is on road - and the FX really shines there. The other 20% is on gravel paths and groomed woodland trails, which the FX handles just fine with rigid forks. If I were doing any remotely challenging off-road riding, I'd want an actual mountain bike. If I had a DS, I'd be locking the forks 80% of the time (i.e. - they would literally be useless dead weight almost all of the time) - and it would be a bit of a PITA for the rest of the 20% as my typical loop transitions from road to gravel to road to woodland to road etc. a number of times in one outing.

Those are just my preferences. Someone with different preferences will choose the DS and be just as happy with their choice. Try 'em out - you'll know which one appeals to you most.

The question is whether you need the front suspension. If you're planning to ride rough trails and single track, then the DS is the right bike. If you're planning on roads and groomed trails, go with the FX.

But I agree with your bike-shop lady that the upper-end FX bikes (the 7.6 and 7.7) are really flat-bar road bikes. Seems to me that you would want a 7.5 or even a 7.4 for the best hybrid capability. By that I mean a wider tire (the 7.4 has 28 mm) and lower gears (while the 7.4 is a compact, it has a 50/34 up front, and 9-speed 11-34 in back, so you have that nice 1:1 ratio for steep climbs). In comparison, the 7.6 comes with 25 mm tires (great for roads, a bit thin for trails) -- it does have a nice 11-36 rear cassette though. The 7.7 is really a flat-bar carbon road bike.

I think some test rides are in order. Do you have a good LBS nearby?

Oh please...not another rigid vs. sprung discussion.

Only thing I will add is that the fit of the FX and DS are quite different. The FX has what is being called a "fitness" posture, the DS wants you to be a little more forward (not full on cross-country mountain bike forward though). Either can be tweaked towards the other somewhat (mainly via stem positioning and/or swapping).

OP, get fitted for and ride all three -- for extended periods if at all possible -- on the kinds of surfaces/in the kinds of conditions you most anticipate using the bike (you are intending to spend some decent money; a good bike shop should be willing to help you make an informed decision). One should 'speak' to you more than the other two (the three are distinctly different beasts, notwithstanding that two are called 'FX').

Three thoughts:

1. If you prefer the handling of the rigid bikes (you may not), but want a little more 'cush' to your ride, remember that the 7.6FX will take tires up to at least 35, and possibly 38 width. An easy and relatively inexpensive change; wider tires can be run at lower pressure with no increase in rolling resistance. Result is more suspension on rough surfaces. The 7.7 limits you to 28s.

2. If you prefer the handling/feel of the 8.6DS, don't be put off by all the talk one hears on this board and elsewhere as to how "suspension is totally useless/unnecessary unless you are really mountainbiking" etc. blah blah. Some people simply do prefer active suspension, even on the road; seems reasonable to me. If that's what you prefer, that's what you prefer. What matters is whether or not the bike in question has a decent fork; the 8.6DS does. The Suntour fork on that bike has a proper coil spring and proper hydraulic damping/lockout. I find, even at 62, that I'm fine with a good, light rigid frame/fork with wider tires (32s, in my case) for mixed surfaces, but that's me, not you.

3. If you really, really like the 7.7FX, and end up not concerned about limitations on tire width or load-carrying, go for it, and forget any nonsense about carbon 'asploding' or being otherwise ultra-fragile; it isn't.

Just a couple of thoughts, OP:

1) Carbon doesn't "asplode"! Carbon is indeed a very tough material. However, greater concern about scratches on CF is required, more so than steel or aluminum. Also, if a CF bicycle gets crashed, it can conceal minute cracks that may compromise the integrity of the entire frame should it become involved in subsequent crashes.

2) IMO, DS hybrids are just fine, if they have decent suspended forks and you really do prefer them, for any reason you may have. It's just that, if you're more concerned about speed than comfort (like I am) , then they aren't your best choice. IMO, it would be better to have a quality mtb that automatically sports a decent suspended fork in most cases.

I'll go test ride both. The fx makes more practical sense. But there's something I really like about the ds.

The 7.7 FX is a Domane 4.0 with a flat bar. It's not really a hybrid like the discontinued 7.9 was. Because it's a road bike it has very short chain stays giving zero room for fenders or larger tires, and heel clearance to panniers is a likely problem. Its wheelbase is about two inches shorter than the lower models and it has a steeper fork, giving it much faster handling, and it will be lighter.

Buy the one you fall in love with, as long as it fits you!

However, MHO, is that the FX will be a better fit for your riding, and the lower model will allow you to fit wider tires and fenders.

Sure, I lust after a CF Sirrus, but my back and shoulders would never stop complaining.

No, it is not. It is a Madone 3-series w/flat bar. Very different frames; lower grade carbon, and no 'decoupler' between seat and top tube. That aside, your other points are pretty much spot-on.

Yes, and if I were to choose between the 7.6 and 7.7, I would take the 7.7 any day.

That information is incorrect. The frame is the same as the 3.1, not the 4.0.

i love my fx 7.7 but it's not an all purpose bike - it's my weekend bike - i "fair weather" bike commute on a trek 800 - and place it in the company bike rack - which i am thankful for - but the carbon frame would not survive that rack or the abuse of other bikes placed on the rack.

i would go even lower than the 7.6 - i think will replace my trek 800 - prob next year with a Giant Escape 3 as my all purpose commuter/errand bicycle.

Are carbon frames that vulnerable, or are you worried more about the aesthetics? Just curious.

How about the giant escape Rx or escape Rx carbon? I think my local shop that has the trek fx's and ds's in stock has the escape 1 and escape Rx carbon in stock but no regular Rx.

How about the Surly Ogre?

This would be my first carbon fiber bike so is be more apt to be careful with it. While I can control myself and have respect for other peoples property i can't say that the others will. Accidents happen no matter how careful - get a nasty scratch from someone's pedal as they are putting their bike on the wall rack next to my bicycle is something I rather not chance on a $2k bike - not the most expensive or the least expensive.

I think I find new scratches on my old commuter bike every couple of days.

Why are you considering a carbon fiber commuter?

Ummmm being a new owner of a 2014 7.7fx all I can say is this bike is fun as lava surfing in hell good times. I used to own the 7.3fx and that was a great bike I rode everywhere and didn't mind leaving it chained up. I will tell you this a 2k hybrid is something you don't leave unattended so take that into consideration. With mods and computer this damn bike is getting more expensive than some of my mates cars! I will say this the dang bike is fast and looks so sharp.

Imo the 7.7fx isn't a commuter it's the sports car you take out on sunny days and wash when you get back home. If you buy the 7.7 it's going to make you wanna ride a lot.

Imo get it and ride it like you stole it.

Because I would only go to work with it which is about 1.5 mikes away and it would be kept inside. It would primarily be a fitness bike/something to just go out for a ride on and have fun.

So you want a fat tire dual sport bike you can take to the trails, or you want a light fast carbon fiber road bike with flat bars. Two completely different types of bikes. Frankly, neither makes much sense for what you want to do. While I understand there are people who prefer road bikes with flat bars, why do you? If you want a cf road bike for fast weekend road rides, I would consider a bike with drop bars like Trek Domane, Cannondale Synapse, or Giant Defy.

You want something rugged and versatile? Consider the Surly Troll, Salsa Vaya, or Cannondale Bad Boy. Want an all rounder? Giant Escape, Jamis Coda, or Trek Fx 7.2 or 7.3.

I recently went through what you are considering. My choices were between the FX 7.4 and DS 8.4. The FX is a great bike! Light, quick and fun. I could have really enjoyed it. In fact, I really wanted it!
However, when I considered my current riding considerations, I picked the DS 8.4. It is nimble, fun and fast as well. It is heavier than the FX, but when I added up everything, I knew the DS was what I wanted.

I am not ruling out an FX being in the shop one day, but where I live and the type riding I do, I don't think it would get as much ride time as the DS does.

I just completed my first organized ride last week, 33 miles. The DS did fine. The only problem I had was 10 miles of nasty headwinds. As a note, I saw several FX bikes on the same course I was riding on.

I would test ride any bike you are considering and honestly evaluate the type of riding you will be doing with it.

Good luck!

There is no Domane 3 listed on the Trek site. Discontinued?

Still, it's not like the 7.9.

Cmon man, you didnt even look.

Madone 3.1 - Trek Bicycle