Trek FX2 Tire Widths?
#1
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Trek FX2 Tire Widths?
I just blew a 1-1/2" tear in my rear Bontrager stock tire and innertube this weekend. I had to carry it a few miles back to the car. So, I am going to have to be replacing, and I will do both at ine time. After searching best hybrid tire choices, I came upon the Continental Grand Prix 4 Season. I am looking for a faster road tire option that has less rolling resistance. This seems like a possible good choice. There is only one problem that might come up. I think that my tires are 700 x 35 mm, and the Continentals seem to only be offered in 700 x 32 mm as the only close fit. How do you know if alternate sizes can fit this rim, and will this tire size fit my rim properly?
Thanks,
Danny
Thanks,
Danny
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Which year is it? You can get the info on the Trek website? Going narrower isn't going to be a problem. It does lower your top gear a tad but otherwise it's ok. Ride will also be a bit more harsher. Try the Grand Prix Urban or Gravel King Slick or Semi Slick @ 35mm.
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pictures of a bike with 32mm GP4S (top pic) and 35mm GK SS (bottom pic)
the 32mm GP4S measures 32mm ; 35mm GK SS actually measure around 37mm
also had 32mm GK SS on this bike at one point; they actually measured around 31mm
the bike feels faster on smooth roads with GP4S installed
Last edited by t2p; 09-04-22 at 12:08 PM.
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The circumference and diameter of the tire usually shrinks slightly with a narrower/thinner tire, because of how the profile of the tire sits on the wheel. It's miniscule but can affect gearing a smidge, as the narrower tire's circumference is smaller. Then again, you gain on weight (lighter), aero and rolling resistance, which will cancel out that and more.
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In general, however, yes, a smaller tire will reduce your top gear.
Edit: I missed your question...why? It lowers the top gear because it has a smaller diameter. A tire with a larger diameter will move the bike further with one full revolution than a tire with a smaller diameter. At the same tire rotation speed (which is driven by your pedaling cadence and gear ratio), your bike will be moving a shorter distance with the shorter diameter tire. Again -- the difference here is relatively small -- fewer than 2% change. But, it's there in theory.
Last edited by hokiefyd; 09-07-22 at 06:28 AM. Reason: More clarification
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Danny