stkfox

I don’t see a lot of information on this bike. I have an FX3 (2017) now and want a new bike but not sure the extra $1000 for the carbon sport would be worth the upgrade over a new FX3. I like the blue color, understand the gearing is different, and it’s a lighter bike. They’re backordered in my region until Jan 2022, so can’t see one in person for closer scrutiny. Does anyone have one? Input would be appreciated.

MRT2

I don't have an FX4 carbon, but it is pretty easy to see the advantages of the newer bike. 1 x 11 drivetrain for the new FX 4, vs 3 x 9 drivetrain on the FX3. Full carbon vs. aluminum frame/carbon fork on the FX 3. Hydraulic discs vs. mechanical v brakes on the FX3. And, 26 lbs or so vs. 21 lbs, but you could shave some of that weight off by upgrading wheels and tires on the FX 3 for a lot less than $1,000.

Is it worth it? I would say no. At least not if you like your current bike, you still have plenty of room for improving your current bike before upgrading. This is especially so given that you can't even get the bike until next year.

MrWasabi

I'm in Tampa too and am looking at the FX4 Carbon as well (and a FX4 Disc). It looks like a great bike to splurge on. If you find one and don't buy it, let me know where in Tampa you found it. I'd probably lean towards a FX4 Disc if I had them both available in front of me as I don't think I could get all the benefit out of the extra for the Carbon with my current riding. For me, by the time I make any changes/upgrades and spend the money on my 2014 Fuji Traverse, I might as well sell it and get a new bike. I've already made my mind up on that, it's just finding a bike in stock.

Good luck!

jaxgtr

I found a really nice used FX4 Carbon as a new bike for my wife. They are super nice and she loves the 1x setup. One of out local Trek dealers has...well had one when I was in there last week, so they can be had. The FX4 has a really nice component setup as well compared to the FX3.

stkfox

Yes, I have seen those stat comparisons, gearing, weight, etc. I’ve never had a full carbon bike for a ride comparison to an aluminum frame so don’t know what to expect as far as handling and comfort of the ride. I’ve also seen mention, more than once, in other reviews/critiques of the FX4 that it’s difficult to get up past 20 mph because of that 1x11 drivetrain. That’s probably ok for my normal riding but I do like to get it going on occasion
Probably leaning toward the FX3 now but all kinds of things could happen between now and Jan 2022.

brucedelta

I bought an FX4 3 weeks ago and I found the bike using the online tool that can show what stores have it in stock. After selecting size the stores that have inventory near your selected zip code will show up, but you can change the zip code also. The independent shops were not accurate as when I called they did not have it, but there are many Trek stores near me and they were accurate. One evening the FX4 disk I wanted showed up as available under an hour away and I called the next morning. I was told they got a shipment in yesterday and the boxes were still on the loading dock. He checked it out and told me they got 2 and one was available. He put my name on it and I went to pick it up when it was assembled.

I got a call yesterday from an LBS that a Sirrus X4 which I expressed interest in has shown up if anyone is looking for an X4.

MRT2

That makes no sense. The big gear is 40 x 11, which is a pretty big 98.2 gear inches. At 90 rpm, that translates into 26 mph. At 80 rpm, 23 mph. At a leisurely 60 rpm, you are at 17.5 mph.
I often wonder who these people are who claim to need 120 gear inches.

hokiefyd 

In my riding, 100 gear inches is about as fast as I need to have. In fact, some of my "slower" bikes top out in the mid 80s and that's fast enough in most situations.

I think 120 inches or more are most useful if you're riding downhill and want to be able to pedal downhill at 40+ miles per hour. That doesn't describe most hybrid riders' environments and is probably not exactly useful for many of us.

MRT2

Way beyond what I want to be doing. I usually sit up when I find myself approaching 30 mph just to catch a little air and slow down a hair. And that is my point. I can pedal at 80 to 85 rpm all day long, 90 when I am feeling energetic. And I am not elite athlete. Therefore, my average speeds seldom go above 14 mph for a ride, and seldom do I go faster than 20 mph on flat ground. depending on the wind conditions and elevation, might even be a bit slower. Which brings me back to who these people are who need to go over 32 mph at 90 rpm, as opposed to 26 mph at 90 rpm? That is the difference between 98 gear inches and 122 gear inches, or 40 x 11 vs. 50 x 11. Maybe someone who does a lot of fast group rides, maybe races a bit. But then, is that person buying a flat bar hybrid?

brucedelta

I am new to biking and still not very fast on the cadence on a real bike. I have the FX4 and 60 is my comfortable cadence right now although I would like to raise it. I do not think I have ever approached 17 MPH unless going downhill.

Interestingly enough I have been thinking a lot about cadence since my on my Peloton 80 seems comfortable, but I struggle to hit that on the bike. I am going to make a concentrated effort to maintain 75-80 and higher resistance to hopefully improve what I can do on the real bike.

jskash

Why is the 1 x 11 drivetrain an advantage? I have only ridden 3 x drives the last eight years.

jaxgtr

Hmmm, well...I changed the brake pads and after I bedded them, I took it for a spin and I easily got over 25 mph.. I changed the cassette from the 11-34 to a 14-28 and I live in a very flat area, .so, not quite sure about that.

MRT2

Me too, but triples are on their way out, so if you are buying a new bike, or replacing components on an old bike, you will likely face the choice of 1 x or 2 x systems. With an 11 speed or 10 speed system, especially with very wide cassettes with 40, or 42 tooth options for the easiest gear, you should be able to optimize the gearing to your riding style and not need a second chainring. With a 9 or 8 speed, you might need to go to 2 x as an 8 or even 9 speed 11 - 42 cassette will have some huge jumps between gears.

DarkSkyHUnter

I've only been dropped once in 50x11 on my FX 6 with some fast Roadies. We picked up the pace on a 1% downgrade. I was spinning out and thought I was in the Small Ring. Nope I was in the Big with a 100 cadence cruising at 33 mph.

With that said, unless you're averaging 20+ mph, 40x11 is a large enough gear for most people with an average speed <=18 mph. I ride with inner Barends on my FX 6 for those wondering how I can average those speeds on a hybrid.

stkfox

Well, called the Trek dealer yesterday and they had rec’d two Carbon FX4s. Just back from checking them out and I have to say, I was really looking forward to bringing one home, but didn’t.
Beautiful color (aquatic blue), very lightweight, and rides smoother than my aluminum FX3. The single drive 1x11 shifted well and was easy to manipulate. I’d consider myself to be a bit above an average rider and I have to reiterate what I’d read in many of the bike forums I frequent that the top gear just doesn’t seem fast enough, sadly.
I did a pretty decent test run in a large lot behind the store got up to some major speed easily and it felt like I could have used a couple more gears to go through. Maybe because it’s a lighter bike?
Long and short, I didn’t think that the extra $1000 for this bike (over a newer FX#3) just to have a smoother ride, yet wanting more speed would suit me.
I’d brought my own FX3 to ride as a comparison and although there were obvious differences in the ride etc it didn’t justify the money.
I’ll wait patiently for either a 2021 FX3 to show up or maybe for the Covid backlog to subside so they bring out new models. Either way it’s my tried and true FX3 for the time being.

MRT2

If you have some money and are just itching for an upgrade, have you considered upgrading wheels and tires? You can improve your ride with more supple tires, and shave off at least a pound or two of rotating weight.

DarkSkyHUnter

The FX4 Carbon has identity issues in it's current form. The gearing is for gravel, but the tires are for the road. I think this would be a fun gravel bike with a simple tire change.


I personally think Trek should have experimented with 1X systems on the Verve, before moving over the the FX series. Unless a 'proven' break through in bike tech comes out, I don't see a 1X system practical on the road for some time. You're always going to want a big chainring for Sprinting, Descents and Tailwinds and a small chainring for Climbing and Recovery.

MRT2

I supposed a 2 x 11 system could really optimize the gearing. Maybe something like a ultra compact system with 46 - 30 chainrings, mated with an 11 - 32 cassette. Or even a 44 - 30. Maybe get the best of both worlds. I am of 2 minds about this. In theory, I can see myself riding a 1 x 11, but what I don't know is whether the big jumps between middle gears would bother me or not.

MrWasabi

I can't PM you. Can you PM me the dealer you saw them? I'm interested and in Lutz.

Thanks.

stkfox

I can’t PM, I have less than 10 posts according to the admin. The store is Dave’s World Cycle in Carrollwood. He has two of them, medium frame.
(813) 963-5765
Good luck.

DarkSkyHUnter

It depends on how you setup your 1X. You could design a smooth 1X for flat ground only. Have a 44x11-25(28).

But if you need the wider range of gears, stick with a 2X. I'm glad I went with the FX 6 over the 4. I would be dropped on faster group rides with the FX 4.

hokiefyd 

I've recently started playing with a 1x setup on a few bikes (both 1x9s). One bike has an 11-46 Microshift Advent setup and the other bike has an 11-40 Sunrace cassette with the rest being typical Shimano driveline parts. The 11-46 is paired with a 26t chainring on a fat bike and the 11-40 is paired with a 32t chainring on a mountain bike, but that's not all that relevant to this discussion as you were asking about the jumps. If you're used to a traditional 11-28 7-speed cassette, and the steps available there (11-13-15-18-21-24-28), then I think you'd be comfortable with one of these cassettes. The 11-46 uses a spacing of 11-13-15-18-21-24-30-37-46. The 11-40 uses a spacing of 11-13-15-18-21-24-28-34-40. Both cassettes use the exact same smallest six sprocket tooth count that an 11-28 7-speed cassette uses. The 11-40 even uses the same seventh sprocket tooth count, while the 11-46 ups it just slightly from a 28 to a 30. The point being, the gear jumps in your faster speeds are pretty reasonable in my opinion (no different than what you may be used to). In these cases, the second largest and first largest sprocket simply expands the range and goes a long way to mitigating the lack of a smaller ring up front.

The approach I took with spec'ing these was finding a combination of cassette and chain ring that gave me the highest gear inch range that I wanted for high speed travel (these are about 80-85 gear inches) and also provided the low speed torque for off road riding (these are about 20 gear inches). Obviously, adjusting the chain ring to something like a 38 or a 40 would shift that gear inch range up in the scale (to many something like 30-100 gear inches). Something like a 44 would shift it even higher (maybe 35-110 for example). It's all about figuring out what you want your gear inch range to be and then doing the math (which is pretty easy -- I have an Excel spreadsheet) to figure out the tooth counts.

Mike2246

Just purchased this model, has anyone upgraded the wheel/tire or handle bar/seatpost? If so models? Looking to trim weight, make it easier on long mostly paved hill rides

msalvetti

I've had one since March 2022, but have pretty much left it alone. Switched to a Brooks B17 seat, but that's it. Will be interested in the responses you get.

Mark

jaxgtr

Yes... I put some Bontrager Aeolus Pro 37's on my wife's bike and running Pirelli P Zero Race in 28's on it. Rides like a dream. I have not swapped out the bars or seat post at this time. Although I used to own a Trek CrossRip that I converted to a flat bar commuter and I replaced both the bars and seat post with a Bontrager carbon bars and seat post and they were fantastic.