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Replacing 700 x 40c tire with something more narrow?

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Replacing 700 x 40c tire with something more narrow?

Old 09-01-18, 05:38 PM
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Replacing 700 x 40c tire with something more narrow?

Hi All - I'm debating whether to buy Raleigh Merit 1 or a Raleigh Willard 2. I like the components (Sora) better on the Willard, but the Willard comes with fairly wide tires (40mm) installed.

Can I replace these tires with a much narrower tire? I was thinking something like a 32mm or maybe even a 28mm tire. I plan to ride the bike on pavement and sandy/hard packed gravel bicycle trails (MUP trails).

How can I tell if the rims are too wide for a 28mm tire?

Thanks in advance!
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Old 09-01-18, 06:48 PM
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Why don't you try riding the wider tires at sensible pressures and see how you like it? Wider, harder tires are not always faster but they are less comfortable.
Here is a chart with some suggested tire/rim size combinations: https://www.sheldonbrown.com/tire-sizing.html Scroll almost to the bottom.
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Old 09-01-18, 08:14 PM
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The general idea is to have the mounted width of the tire no less then the rim's (outer) width. In the recent and farther back past most wanted some bulge of the tire beyond the rim width. These days the trend is to have the tire pretty close to the rim width.

So 32mm labeled tire (note the labels are not actual measured widths) might fit on a rim as wide as 30mm but would be considered pretty wide for a 20mm rim. Some rim manufacturers have compatibility charts for viewing. Andy
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Old 09-01-18, 08:27 PM
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You might consider getting a high grade wide tire (like Compass), which gives you the best of both worlds. Many of us wish we could fit wider tires on our bikes. I have a bike (and wheels) that handles everything between 28 mm and 40 mm with no issues. I've settled on 38mm Compass tires (two sets, one with treads, one without). I don't notice any penalty vs. narrower tires.
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Old 09-01-18, 08:58 PM
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From the website:

Raleigh Alloy Double Wall, 700c, 28 Hole

Not much info there. My guess is it's about 19mm internal at most and will work with a 28mm tire.
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Old 09-01-18, 09:58 PM
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I've been running 28mm Kenda Karvs on my flat bar commuter road bike. I tried them out on some dirt, when it had drop bars and friction DT shifters (yikes!!!), and they worked pretty good on somewhat packed surfaces. They are a shallow knobby, lightweight, and roll quite well. The only downside is that they wear quicker than I'd like.

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Old 09-02-18, 12:37 AM
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Definitely try the 40mm tyre at a sensible pressure before going slim. That's not to say slim tyres don't have their place, but you may be surprised by the riding characteristics of a wider tyre. I don't ride 40mm (mine are 32 I think) but I love the confidence they give me while cornering - something I don't get with 23mm...
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Old 09-02-18, 06:15 AM
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I just picked up an almost identical bike used, with 38s mounted. Right away I changed them to 25s. I hardly ever leave pavement (lots of MUPs), and I enjoy lighter weight and higher pressure. And the people I ride with do the same. I didn't measure exactly, but my rims appeared to be about 22 mm external width, fairly standard wide rims. As noted above, as long as the tire is wider than the rim, it'll be fine. (I think I'll try 28s when the 25s wear out.)
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Old 09-02-18, 10:29 AM
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Much narrower? Below a 700 x 32 width tire you may run into instability on unpaved surfaces. Yes, a 700 x 40 tire is wide, but exactly what tire are you talking about? If the tires supplied with the bike are really good quality you may gain little to nothing to less than nothing when you ride on unpaved surfaces, especially if the trails and paths you ride on have sections where the surface is soft. A wider tire will roll over soft sections without you even noticing. A much narrower tire will dig into the soft surface and create an unnerving experience
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