DreamRider85

Part of the reason I got the FX4 was for it's upright position. I use it on days when I want to give my neck, wrist and back a rest. I'm a bit slower on it though. The tires are wider. I'm wondering if anyone has tried putting road tires on that particular bike. Is there a big downside if I ride mostly paved roads?

dedhed

I have run 25's on my Raleigh hybrid for years as I used it for a road commuter.

mstateglfr 

Tire width isn't nearly as detrimental to speed as you seem to think.
A high quality slick tire can be fast rolling even if it's 35mm wide.
Conversely, a low quality 28mm tire can be heavy and slow even if it's thin.

You will always be slower if you ride upright because wind resistance is the biggest impediment to speed.

But yeah, just buy some quality fast rolling slick tires, even if they are 35mm or 38mm wide.

Schwalbe RS gone Super Race 35
Panaracer GravelKing slick 35
Continental Grand prix urban 35
Schwalbe Marathon Almotion onestar 40


..these are $34 right now- https://www.rei.com/product/152159/c...E&gclsrc=aw.ds

Metieval

You don't need skinny (road) tires to be faster. You just need better tires.
Depending on your roads higher volume tires could be faster.
If you want a road road tire though put on a 32c gp5000.
Or try a 700x35 or 38 protite pasela with a tpu tube.
Honestly the 38c protite pasela will be faster than your upright riding position and also be super comfy! Better on your neck and wrist.

jpescatore

I put 32mm old style old style Continental tires on a hybrid, big improvement on pavement and no need to go narrower. Just about any tire with a solid center patch will have lower resistance than your GR1 gravel tires. And you don't need to overinflate either - 75 psi or below, depending on your weight. Check out the Silca tire pressure calculator.

If you spend more money, you get lighter tires which may be faster but you might notice it and the tradeoff is weight savings/speed gain at the cost of puncture protection. Bicyclerollingresistance is a great site to see test data, though. I have a gravel bike with 40MM gravel tires that never flatted in mixed riding - you'll be facing more normal odds with road tires on the road!

soyabean

Rolling resistance only kicks in when you are doing decent mileage.

Having to huff and puff an extra 10% over 5 miles isn't really going to be a problem over watts/calories.

Schwalbe balloon tyres have some of the lowest rolling resistance and they run on 2 bars.

https://www.schwalbe.com/en/balloonbikes

DreamRider85

Is there anything wrong if you put 28 mm road tires on it? I keep seeing 32 and above recommendations. Would it be the same as a road bike, but just upright? I try to go good mileage.

Iride01 

If road tires are just something with less tread pattern, thinner and more supple tread and sidewalls, then you might get a better ride with less rolling resisitance. Width of your tire isn't as much an issue. But you might have trouble finding a slick or tire with very little tread pattern on it as wide as your current tires.

You need to know the internal width of your rim to know how narrow a tire you should go. The rim might have it written on it in fine print. Some even give the recommended tire width range. The tire vs rim width in itself can make a big argument here. There really isn't a controlling authority. Just how much risk you wish to assume when you get to the point others think you have gone to far and some say you can go more.

mstateglfr 

My main road bike has 32mm tires. So nothing is inherently wrong with using narrower road tires, but at the same time nothing is inherently better either.

Find the mix of width and tire pressure that you like and buy a fast rolling tire in that width.
The bb drop on an FX bike is not much, it's less than a road bike. So dropping the height of the bottom bracket due to smaller diameter tires isn't a concern since the bb will still be high enough up. That's really the only major concern since your stock rims aren't too wide to take a 28mm tire.

Barry2 

I put Reserve Carbon road wheels & GP 5000 S TR on my wife’s FX4.
Saved all kinds of weight and rolls!

She loves it.

Barry

Metieval

You could put a 23 on it and be fine. Super fast too. But a 23 on a wide wheel, leave an undesirable shape on wet roads. Think landing on the heal of your shoe on a wet tile floor.
You be fine with a 28c if thats what you want.

mstateglfr 

The image they use in that link to price low rolling resistance is comical.


What is a 'Standard 37' exactly? Everyone knows tires vary widely in design, construction, inrended use, cost, performance, etc.

I also love that they include 5 bar, so 72psi, as a column. Like...what? No 60mm wide tire will be ridden at that psi.

jaxgtr

My wife and I have run Pirelli P Zero Race in 28's on our FX's and it was fine.

freeranger

Don't think you need to worry too much about wider being slower, at least not according to Rene Herse, and they should know a thing or two about tires: Why wider tires are NOT slower – Rene Herse Cycles

DreamRider85

So it appears that wider tires don't make you slower. But let's talk about endurance. Are the wider tires as good for going a long distance? Anyways, I went to the bike shop yesterday and he says because my Trek are 700, I'm not really able to go lower than 38 mm according to the specs. But then some of you say I can go lower. Does anyone know about this? I'd love to have a road bike feel with the flat bar, but I'm trying to weigh all my options.

mstateglfr 

Per Trek's website, the rim on an FX4 is below.
https://www.trekbikes.com/us/en_US/b...ort-4/p/35785/
https://www.trekbikes.com/us/en_US/e...rim/p/5263989/

Product details

1. Replacement rims for Paradigm TLR wheels
2. Durable double-wall alloy rim with 21mm internal, 26mm external width
3. Pinned construction, non-eyeletted
4. Optimize with Bontrager TLR Sealant, TLR rim strips, valve stems, and tires

Its an aluminum rim thats 21mm internal and 26mm external. You can absolutely mount tires narrower than 38mm on those rims. A 28mm tire is fine on there and actually pretty much fits the trendy 'rule of 105' for aero gains. Dont worry about that, its just some nerd deep dive stuff that shows what rim width is best for reducing wind resistance at the tire/rim.
Anyways, yeah you can safely use a 28mm tire, or a 32mm tire, or a 35mm tire.
And with the high bottom bracket, reducing the tire height by using a narrower tire will not result in any danger for pedal strike.


As for long distance...
- a wider tire is typically viewed as being more comfortable because it absorbs more bumps from road imperfections.
- a long ride means more road imperfections.

So a wider tire can be more comfortable for long distance riding, yes. Again though, the caveat here is that the tire is a high quality fast rolling tire. A fast rolling wider tire will keep rolling resistance down while allowing for a lower tire pressure that absorbs road imperfections.

msu2001la

Your bike shop is selling some nonsense. You can run 28mm tires on those wheels and there's nothing inherent about the bike that would require wider tires.

I would recommend trying a high quality 28mm or 32mm road tire like a continental GP 5000.
Most of the pro peloton is racing on 28mm tires these days. Almost everyone I know who's doing fast club/group rides and amateur racing is on 28mm. There's really no need to go any narrower.

Iride01 

Without knowing your rim width anything we say is definitely a guess.

I ask you earlier if the rim size was written on the rim. Did you ever answer that?

However I'd think for that bike you should be able to go lower than what the bike shop guy said. But then again, at least they got to see the rim, whether they actually knew anything or not, who knows?.

On my son's 29er which is the same BSD as a 700C, we put 32mm tires on it for the road. Thick tread is what will make your riding on the road harsh and take more effort. You want slicks or minimal and thin tread pattern on paved roads. IMO.

jpescatore

I do many 60 to 100 mile rides each year on 32mm tires - wider is not slower or higher rolling resistance for normal human beings.

Now, if you are going to ride at 25 mph, the aerodynamic advantage of more narrow tires becomes a factor - but even the pros are up to 26 to 28 mm and sometimes 30mm tires on the Tour de France! On rough roads on other races, even 32mm!

But, if you are more likely to average 15mph, and most of your riding is not on glassy smooth roads, you aren't gaining anything going smaller unless you just want to emulate your favorite pro rider.

t2p

for reference

pictures of two hybrids - one with 32mm tires (top) and one with 28mm tires (bottom)

(Continental GP4S tires)

DreamRider85

Alright here’s my update: the last shop told me I wouldn’t be able to get tires under 38 mm and put them on my trek sport 4.

But I went to a different shop. They had 35 mm hybrid tires. What I’ve noticed about my bike is it feels different. It feels lighter but I feel like I’m spinning my wheels more. With the bigger gravel tires, I felt like I could put more power into it with the heavier weight.

So I’m getting used to it. It feels light but unless I put it on level 10, it just feels like I’m spinning the wheels.

tFUnK

And that's a good thing! You probably lost a couple hundred grams of rotational mass with the switch 👍

A 35mm would be what I'd have recommended if your frame could fit it (which you've confirmed). I don't know if you're running tubeless but if not, some TPU tubes would shave another 100g per tire.

mstateglfr 

What brand and model tire did you end up with?

wheelreason

That "feeling" is common for folks moving up from recreational bikes to more performance oriented ones, or as in your case changing the riding characteristics of the bike. Often the feeling is described as unsteady, twitchy, or as in your case less solid. This is normal. You will get used to it. To minimize the spinning to easily thing, just shift up a couple of cogs, Mcnuggets for lunch...

t2p

agree with the 35mm recommend - good versatile size …

mrs t2p old school fx wears 35mm GK SS … they actually measure almost 37mm - which is a plus except I need to shoehorn the front wheel / tire between the brake pads when removed / installed