Trek FX 7.3 - Drop Bar Conversion, Max Tire Width, and Other Exploration
#26
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#28
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Tyre tolerances on a smaller frame
Hi, I'd just like to say how interesting and useful a read this was for someone in a similar situation with a 7.3 FX.
A bit of a newbie question, but would having only a 17.5" frame size and tyres with some tread make that clearance too little on 700c X 42? I was looking at Continental Contact Plus tyres.
Maybe those things don't affect the gaps but I wanted to make sure.
A bit of a newbie question, but would having only a 17.5" frame size and tyres with some tread make that clearance too little on 700c X 42? I was looking at Continental Contact Plus tyres.
Maybe those things don't affect the gaps but I wanted to make sure.
Last edited by Krabix; 05-12-23 at 03:54 AM.
#29
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Just out of curiosity, how much did the bike plus rebuild cost all in?
#30
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Man if it ain't broke...
I cut 20mm off the steerer, swapped V-brakes, and put on larger rings. It's down to 20.3x lbs, and that's after putting lighter wheels and tires (slightly smaller) to get it to 20.0 lbs on the nose, but it just didn't have the life that it did with these DT Swiss wheels and larger 42mm Soma tires. 53/39 chainrings for bombing down hills do gear me up, but look super legit and I don't spin out on long downhills, which was a goal. The TRP mini-Vs from a different build hug the 42s really well. I dropped a little weight with them, but they look the business, stop well, and really complement the componentry. Long wheelbase, big roll-over-anything tires, comfortable critical components, light weight and lively, killer looks--what more does a guy need? Cool part is that one can replicate this for a ton cheaper (and a pound or two more in weight, still light!) if they just chuck some R3000 Sora on it and bump to bigger tires!
Glam shot. In real life, it's even more of a butch-yet-sleek road bike+. Love it.
You can get equal performance from other, much cheaper mini-V brakes and normal-length V-brakes that weigh nearly or essentially the same, but they won't look as hot as these. At least to me. [not that the stock FX V-brakes looked bad--they looked totally fine!]
Best looking modern crankset, IMO. Still. Looked great with the 50/34 combo, but stepping up to the 53/39 was almost intimidating as it now looked like a Real Road Bicycle crankset that I better have a worthy frame to hang it off of. Gulp.
Ultegra 6800 11-32T cassette run by a standard Dura-Ace 9000 rear derailleur with a 6800 GS cage setup. Don't be worried about making it work, people! Also, I show this as, to keep the new chain clean, I cleaned not only the faces of each cog, but the flats of every single tooth/valley between the teeth. This is the, maybe, second time I have ever gone to that length to clean a freewheel/cassette. I am glad it's over!
I cut 20mm off the steerer, swapped V-brakes, and put on larger rings. It's down to 20.3x lbs, and that's after putting lighter wheels and tires (slightly smaller) to get it to 20.0 lbs on the nose, but it just didn't have the life that it did with these DT Swiss wheels and larger 42mm Soma tires. 53/39 chainrings for bombing down hills do gear me up, but look super legit and I don't spin out on long downhills, which was a goal. The TRP mini-Vs from a different build hug the 42s really well. I dropped a little weight with them, but they look the business, stop well, and really complement the componentry. Long wheelbase, big roll-over-anything tires, comfortable critical components, light weight and lively, killer looks--what more does a guy need? Cool part is that one can replicate this for a ton cheaper (and a pound or two more in weight, still light!) if they just chuck some R3000 Sora on it and bump to bigger tires!
Glam shot. In real life, it's even more of a butch-yet-sleek road bike+. Love it.
You can get equal performance from other, much cheaper mini-V brakes and normal-length V-brakes that weigh nearly or essentially the same, but they won't look as hot as these. At least to me. [not that the stock FX V-brakes looked bad--they looked totally fine!]
Best looking modern crankset, IMO. Still. Looked great with the 50/34 combo, but stepping up to the 53/39 was almost intimidating as it now looked like a Real Road Bicycle crankset that I better have a worthy frame to hang it off of. Gulp.
Ultegra 6800 11-32T cassette run by a standard Dura-Ace 9000 rear derailleur with a 6800 GS cage setup. Don't be worried about making it work, people! Also, I show this as, to keep the new chain clean, I cleaned not only the faces of each cog, but the flats of every single tooth/valley between the teeth. This is the, maybe, second time I have ever gone to that length to clean a freewheel/cassette. I am glad it's over!
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#31
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Hi, I'd just like to say how interesting and useful a read this was for someone in a similar situation with a 7.3 FX.
A bit of a newbie question, but would having only a 17.5" frame size and tyres with some tread make that clearance too little on 700c X 42? I was looking at Continental Contact Plus tyres.
Maybe those things don't affect the gaps but I wanted to make sure.
A bit of a newbie question, but would having only a 17.5" frame size and tyres with some tread make that clearance too little on 700c X 42? I was looking at Continental Contact Plus tyres.
Maybe those things don't affect the gaps but I wanted to make sure.
Everybody has their level of comfort when it comes to tire clearance. Coming from road riding (and still there), I don't mind pushing things a bit as gaps are tighter anyways. Manufacturers work with 4-6mm of air between a stated tire size and the frame. That's a ton of space for me, so I'll see if it's possible to fill it. Small frames sometimes run into clearance issues, usually in the seat stay area from my limited experience, but you'd have to check. If Trek is consistent, then true 35-38mm tires should be very possible. Manufacturers state tire size, but true size varies with rim width, inflation amount, and however wide (bead to bead) the tire is constructed. It's a bit of a zoo, so I lay a tire flat and measure and chart the bead-to-bead width of a tire to get an accurate idea of how wide it actually will be.
#32
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I have put the bike back together fully stock with the addition of fenders and am selling it. All those other components stay with me and are on different bikes. It's a bit of how I justify things as I like to build, ride, learn, and repeat, just with different frames. A lot of those 9000 components are now on a '09 Specialized Tricross Sport triple (Tiagra mix) that fits massive 48mm tires on those same DT Swiss wheels. I repainted the frame (paint had been stripped 2 owners ago), added decals, got some super flared Salsa bars, and it all came in about half a pound lighter than the FX, even as the FX frameset was a touch heavier to begin with.
#33
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as a lover of trek fx's (i have 2 now, have owned 4 in total previously), i love what you've done to this thing! i have hated the brakes on every single trek bike i owned including a higher end trek fx 7.7. they're so bad and always catching the wheel. these look more pro! your reviews of the brakes so far....?
I've had pads that were really lackluster (Shimano 105 5800, fresh off the shelf) and others that surprised me (TRPs, random 35 year old Shimano 600 pads on old Matrix wheels), and still others that surprised me even more. I've run hydraulic disc brakes before a few years ago--all Shimano Ultegra level stuff, rotors included. They were alright. So I don't buy the disc brake hype, especially when it comes to dealing with rotor warping and pad contamination/noise. For all the sent-from-heaven hyperventilating about hydro disc, the hardest I've ever felt (for surprisingly little effort) is a combination of Dura-Ace 7402 levers paired with Dura-Ace 7800 brake calipers and Kool Stop pads. Absolutely vicious, even for me at 200 lbs. I forget the rims. They may have been old Mavic MA2s, which I do like a lot. Seems like machined sidewall (think Open Pro and anything modern) can be either pretty good or a bit smoother/more indifferent.
I guess this is a long way of saying "It depends!" which doesn't help. There are general proven products and setups, but there are also enough surprises to make one question things. Usually hybrids with their V-brakes stop a lot stronger (and more confidently) than road bikes, to me. I mean the lever and v-brake physics are logically superior, so when they work, they work.
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#34
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I recently picked up another 7.5FX, also in like-new condition(2010 model), for $190..quite a score. I'm converting it now, using all new components, and using new 3x9 Microshift shifters($120). Costs will be about the same as the blue one. The red one will be left at & used at a vacation home we purchased recently.
The total costs of a conversion like this can be quite a deal. In our, actually my wife's experience, it's a road/gravel bike that is very lightweight, it FITS her (they are WSD frames), and can run 38-40mm tires for a comfortable ride. $500-$600** doesn't get you far when you start looking for a used gravel bike that can match one of these conversions. I target 7.5's and above..they have better component groups and a carbon fork. Parts are arriving for the red 7.5 conversion. I'll post a photo when I get it done.
**Between my wife and I, we have about 12-13 bikes. I've never purchased a used bike yet that didn't need $100-$200 is refurb-upgrades..so a $500 bike is typically more than $500 when the dust settles.
Last edited by fishboat; 05-14-23 at 07:18 AM.
#35
Newbie
Thanks for the inspiration!
Hey guys,
Amazing thread! So much so that I've gotten myself a 2012 fx 7.3, did the drop bar mod, and put about 1000 miles on the clock in the meantime.
I have an interesting finding when it comes to a caliper brake mod (tektro r559). Tldr, works amazing, easy to do. If someone is curious about my findings, please let me know
Cheers!
Amazing thread! So much so that I've gotten myself a 2012 fx 7.3, did the drop bar mod, and put about 1000 miles on the clock in the meantime.
I have an interesting finding when it comes to a caliper brake mod (tektro r559). Tldr, works amazing, easy to do. If someone is curious about my findings, please let me know
Cheers!
#36
Newbie
Thanks for the inspiration!
Hey guys,
Amazing thread! So much so that I've gotten myself a 2012 fx 7.3, did the drop bar mod, and put about 1000 miles on the clock in the meantime.
I have an interesting finding when it comes to a caliper brake mod (tektro r559). Tldr, works amazing, easy to do. If someone is curious about my findings, please let me know
Cheers!
Amazing thread! So much so that I've gotten myself a 2012 fx 7.3, did the drop bar mod, and put about 1000 miles on the clock in the meantime.
I have an interesting finding when it comes to a caliper brake mod (tektro r559). Tldr, works amazing, easy to do. If someone is curious about my findings, please let me know
Cheers!
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#37
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mrs t2p 7.5 FX
recently showed it some love with upgrades including 35 mm Panaracer GK SS
the tires actually measure around 36-37 mm installed - and this width is the max for this FX : the front wheel / tire must be squeezed / shoehorned through the open front brake pads when installing ... a tire 1 mm wider would prob not work (without deflating the tire)
Last edited by t2p; 06-01-23 at 07:32 PM.
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#38
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To answer your question: no, I did not say/do not think that. You took a select portion out of a paragraph that was dealing with a larger topic and then applied them to a gravel application that I never spoke of or alluded to. Granted, that second sentence (which was really a fragment) is incomplete, which is an unfortunate product of a million thoughts not coming out in order/coherently. Sorry about that.
Anyway, let's start with an empty table here and put some basic things on it so we can all start at a common premise:
1) One can make a steel frame really nice or really harsh. One can make an aluminum frame really nice or really harsh. One can make a carbon frame really nice or really harsh/dead.
2) Some riders can be sensitive to how a bike feels. Other riders either don't care or can't tell differences in bike feel. A bunch of other people are somewhere in the middle in that regard. And then there is preference and tolerance on top of that.
3) There are wheelsets that are heavy but decent feeling. There are wheelsets that are heavy and brutal. There are light wheelsets that are harsh/brutal. There are light wheelsets that feel great.
4) There are Apocalypse-Ready Anti-Puncture 9,000,000 Quintuple Marathon TPS 8.750 Dual Iron Rhino XXXXXL Hunny Bun Pass tires out there that do their job well but are as heavy as a battleship and ride like a brick. On the other end are tubulars. Near those tubulars are supple, light tires of larger than race bike volume.
This is all to say that there are considerable variables when it comes to the frame, the components, and the rider. You could add saddles in there as well as major factors that give a certain range of experiences. Heck, put proper fitment in there, too. I do not know your riding history or style or preferences outside of what you've just told me, so I can't prescribe a specific solution. However, I have built and ridden many bikes from road/race to sport touring to touring to gravel, and am pretty tuned in to both obvious and subtle characteristics.
A solid steel frame with proper/relaxed geometry, sturdy wheels, and beefy tires will probably feel reassuring and steady on gravel (or road) due in large part to the weight of the bike and its handling characteristics. Will it be fast or spritely? Not likely unless you're a beast or like rocking down hill at speed. Heavier bikes have their place and have plenty of benefits, as do lighter bikes that can flit and glide over the rough stuff (or road surface).
I like your ideal intersection of gravel, touring, and endurance. It's about where I am as well. Kinda like bikes long ago, haha. A good vintage touring bike is plenty durable, with good geometry for loads and for unloaded descents. The gravel/endurance element is taken care of by generous tire clearances. A number of vintage sport touring bikes have shorter wheelbases, but still decent tire clearances. I know there is an Endurance road bike category, but until very recently, and with disc, they never really allowed tires over 28mm, which when coupled with the marginally longer wheelbase, didn't seem like an honest effort. The original hybrids took touring and mountain geometry elements and have evolved since then.
The FX and others like it (that can clear big tires) are an excellent option because you can put smaller tires on it and it won't feel slow, as well as put larger tires on it and greatly increase comfort and capability over uneven terrain (they also won't be slow if they have supple casings). If you had to change one element on a bike you have and like, or want to get, to increase comfort and capability, regardless of frame material, in my opinion and experience it would be the tires (and resulting appropriate pressure settings). A change in tire size can move the needle on bike feel/comfort significantly. You can help the frame material component out by paying for a nicer one or a different one, but tires will be a faster and cheaper change. Do you need a Compass/Rene Herse offering at $90+ a tire? If you want. You can get halfway there with a Pasela for what, $35? Or most of the way there with a Soma Supple Vitesse EX like I have (was $54 when I bought new ones, now $65 or so). Crappy tires on cars suck, and we know this. The same is true for bikes.
Glass smooth roads make every bike feel like a hero. Crummy roads or rough gravel require a different solution, and large tires (and the ability to fit them on/in one's bike) do wonders on that front. A Davidson Impulse or a vintage Colnago etc will be amazing on smooth roads, but will bring one to their knees over the rough stuff. Those are top-shelf steel bikes, but can only fit 25-28mm tires. Tubulars and high quality clincher tires ease the hits, but those race bikes are going to be jackhammers, and those steel frames will not be able to rescue their rider. Enter in the FX, a bike decidedly not for racing or fast/competitive riding, made of aluminum largely, with a steel or aluminum fork in most cases, but there it goes on 38mm tires, not bludgeoning its rider to death over bad roads. Put 25s on it and it's as bad as the steel offerings, but go back to the big stuff and it's a much better place to be.
Anyway, let's start with an empty table here and put some basic things on it so we can all start at a common premise:
1) One can make a steel frame really nice or really harsh. One can make an aluminum frame really nice or really harsh. One can make a carbon frame really nice or really harsh/dead.
2) Some riders can be sensitive to how a bike feels. Other riders either don't care or can't tell differences in bike feel. A bunch of other people are somewhere in the middle in that regard. And then there is preference and tolerance on top of that.
3) There are wheelsets that are heavy but decent feeling. There are wheelsets that are heavy and brutal. There are light wheelsets that are harsh/brutal. There are light wheelsets that feel great.
4) There are Apocalypse-Ready Anti-Puncture 9,000,000 Quintuple Marathon TPS 8.750 Dual Iron Rhino XXXXXL Hunny Bun Pass tires out there that do their job well but are as heavy as a battleship and ride like a brick. On the other end are tubulars. Near those tubulars are supple, light tires of larger than race bike volume.
This is all to say that there are considerable variables when it comes to the frame, the components, and the rider. You could add saddles in there as well as major factors that give a certain range of experiences. Heck, put proper fitment in there, too. I do not know your riding history or style or preferences outside of what you've just told me, so I can't prescribe a specific solution. However, I have built and ridden many bikes from road/race to sport touring to touring to gravel, and am pretty tuned in to both obvious and subtle characteristics.
A solid steel frame with proper/relaxed geometry, sturdy wheels, and beefy tires will probably feel reassuring and steady on gravel (or road) due in large part to the weight of the bike and its handling characteristics. Will it be fast or spritely? Not likely unless you're a beast or like rocking down hill at speed. Heavier bikes have their place and have plenty of benefits, as do lighter bikes that can flit and glide over the rough stuff (or road surface).
I like your ideal intersection of gravel, touring, and endurance. It's about where I am as well. Kinda like bikes long ago, haha. A good vintage touring bike is plenty durable, with good geometry for loads and for unloaded descents. The gravel/endurance element is taken care of by generous tire clearances. A number of vintage sport touring bikes have shorter wheelbases, but still decent tire clearances. I know there is an Endurance road bike category, but until very recently, and with disc, they never really allowed tires over 28mm, which when coupled with the marginally longer wheelbase, didn't seem like an honest effort. The original hybrids took touring and mountain geometry elements and have evolved since then.
The FX and others like it (that can clear big tires) are an excellent option because you can put smaller tires on it and it won't feel slow, as well as put larger tires on it and greatly increase comfort and capability over uneven terrain (they also won't be slow if they have supple casings). If you had to change one element on a bike you have and like, or want to get, to increase comfort and capability, regardless of frame material, in my opinion and experience it would be the tires (and resulting appropriate pressure settings). A change in tire size can move the needle on bike feel/comfort significantly. You can help the frame material component out by paying for a nicer one or a different one, but tires will be a faster and cheaper change. Do you need a Compass/Rene Herse offering at $90+ a tire? If you want. You can get halfway there with a Pasela for what, $35? Or most of the way there with a Soma Supple Vitesse EX like I have (was $54 when I bought new ones, now $65 or so). Crappy tires on cars suck, and we know this. The same is true for bikes.
Glass smooth roads make every bike feel like a hero. Crummy roads or rough gravel require a different solution, and large tires (and the ability to fit them on/in one's bike) do wonders on that front. A Davidson Impulse or a vintage Colnago etc will be amazing on smooth roads, but will bring one to their knees over the rough stuff. Those are top-shelf steel bikes, but can only fit 25-28mm tires. Tubulars and high quality clincher tires ease the hits, but those race bikes are going to be jackhammers, and those steel frames will not be able to rescue their rider. Enter in the FX, a bike decidedly not for racing or fast/competitive riding, made of aluminum largely, with a steel or aluminum fork in most cases, but there it goes on 38mm tires, not bludgeoning its rider to death over bad roads. Put 25s on it and it's as bad as the steel offerings, but go back to the big stuff and it's a much better place to be.
#39
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I just picked up a nice 7.3 FX that is set up to ride much more upright and I plan to install a front loading baby carrier. The previous owner installed 28mm gator skins which are fast but make for a stiff ride. What is the widest tire that you recommend for the stock bontrager nebula 6000 series (622x15) wheels? I'm looking to add a little cushion without messing up the handing.