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11

I understand that around 20% of the energy while cycling is lost by the deformation of the [tires] No not really. Rolling resistance will increase linearly with velocity while drag increases with the cube of velocity, so rolling resistance is not a fixed percentage of total power lost. At higher velocity drag will completely dominate. use plain tires (no ...


10

The diameter measurement in an ETRTO specification is the rim bead set diameter in millimeters. You must use a tire with the same bead diameter as the rim of it will not fit. If you have a 622 rim you must use a 622 tire. A larger diameter tire will simply blow off the rim when you try to inflate the tube. With regards to width, there is a maximum tire width ...


9

Regarding diameter: You can't put 26" tires on a 27.5" rim, which it sounds like your son wants to do. I can guarantee with absolute certainty that the new tires will not work because they're the wrong diameter. Regarding width: We don't know the width of the rims on your son's bike. Also, rims can handle tires across a range of widths. It is ...


6

There is always the potential for tolerances to make a particular tire, rim, or combination hard to mount. A rim being tubeless or not per se does not dictate how hard it is to mount a tire on. Tubeless rims aren't made tighter, i.e. their target diameter for the bead is not a larger number than non-tubeless. There has always been a cat and mouse game in ...


6

Now based on that, I was wondering if there is any estimate on much gravel bike tires (with some light tread pattern) might contribute to the loss of energy compared with road bike tires (plain) for the same conditions (dry, plain and smooth road). You don't need to estimate. You can measure. For example, here's one gravel tire: https://www....


4

It's difficult to tell from this picture, but it looks like the casing—the structural part of the tire—has been damaged, so it's just a matter of time before the tire fails completely. Look at the inside of the tire. If the damage has penetrated all the way through, I would stop riding on that tire. If it hasn't, you might be able to get away with gluing in ...


4

Regarding wheel rim diameter compatibility: On mountain bikes, wheel and tire diameters are typically referred to in inch sizes: 26", 27.5" and 29". Those measurements are nominally the diameter of the inflated tire mounted on the rim. However, what they really mean is the tires fit wheel rim bead-seat diameters of 559mm, 584mm and 622mm ...


3

E-bike tires are designed for heavier loads, and faster speeds. Comparing Marathon Plus regular with e-bike version, e-bike has deeper tread, two layer puncture protection, and rubber mixture optimized for higher speed. E-bike one also has max load 6kg higher. For 28 x 1.75 Shwalbe says that regular weights 1100 g and e-bike 1150 g. When I was choosing tires ...


3

Possibly the valve was contaminated with a particle or dirt and was not sealing properly leading to quick but not instantaneous loss of pressure. When re-inflated the contamination was dislodged and the tube holds pressure once again.


3

No. Your current tires are so-called 26 inch and they fit on 559mm rims. The tires you are considering are so-called 27.5 inch and fit on 584 rims. If you for some reason buy new wheels to match the tires, they do not fit your bike. It is likely that they are too large to fit at all, and if they do, rim brakes are in wrong position for the larger rim.


3

In lieu of more information about the bike, the best answer is probably not, but maybe. You can find some examples of bikes that came with 27x1-1/8" that also max out at that size, but they are not very populous relative to ones that could fit a little bigger tire. As always with questions like this, it all depends on the exact tires and rims in ...


2

Replace the tire. A bike has a number of systems: propulsion, suspension, braking, steering, etc. Propulsion is one of the least critical. If it fails, you walk home (or call someone for a ride), but otherwise it's not much of a hazard. Most of the other systems though, a failure while you are on the bike and especially if you are at any significant speed, ...


2

I don't think the holes in the winter tyres will be prone to punctures without the spikes in them. They're a very small target. I have had damage from the inner end of the spikes themselves wearing through the belt on tarmac (occasionally icy). These winter tyres aren't as tough as the marathon plus (tour) though, both in terms of overall puncture protection ...


2

Typically yes, but I am sure there are edge cases (read poor manufacturing tolerances) where this isn’t the case. In order for tubeless tire setup to work you need tight tolerances as the bottom of the tire bead needs to be in firm contact with the rim bead seat in order to make a firm seal. As such the bead seat diameter (BSD) should have less variability ...


2

Yes - I ran 28mm Continental Grand Prix 26" tyres on my recumbent for a while. They were fast, looked sporty and worked well at ~14 Watts Downside, they punctured relatively easily. When it got to ~2 punctures in a week's commuting (10 hours of riding), I changed to Schwalbe Energizer Plus Greenguard 26" x1.75 47-559 tyres on the same rims. ...


2

@NathanKnudson already mentioned the well in the middle of tubeless rims. This merely illustrates why it's necessary to use that well. The picture below is from Slowtwitch.com. For readers not used to tubeless rims, the well or center channel has a narrower diameter than the rim's bead shelves, where the tire beads sit when inflated. I'm not sure what the ...


2

Most modern road bike rim brakes only have clearance for 28 or 30mm wide tires. Unfortunately I’m not aware of any real gravel or cyclocross tire with less than 30mm width. With disc brakes some road bikes have clearance up to ~35mm width. Edit: I should add that older brakes and frames have less clearance, the ability to fit 25 or 28mm tires has really only ...


1

BB height is a measurement that depends on too many ill defined parameters to be useful. A rough approximation for three height of a tyre is to take its nominal width. That leaves us with a discrepancy of about 8 mm. Spezialized seem to have used either a height from the tyre manufacturers data sheet or actually measured themselves. Tyres deviate from a ...


1

A central uninterrupted patch makes the MTB tire "OK" (efficient) for road use. Big side knobs make road cornering unpredictable (because they bend and reduce stability). As for the intended purpose (offroad biking) it's black magic to me. Generally large spaced out knobs(above picture) are for mud, more dense patterns for hard-packed (they fill ...


1

Traditional Dutch bikes were build to take 32 mm tyres, maybe 35 as maximum. All parts were designed on that size of tyre, as that was what was available. (I am talking about 70 to 20 years ago, maybe even shorter time ago.) That is what the Dutch are familiar with, that is what they are used to, that is what they know that works and they do not see reasons ...


1

If you are machinists you probably know about the “bouncing steel ball” material hardness test. The harder the material under test the higher the ball rebound towards its start altitude, always less than 100%. To your question .. The same principle operate in a reverse order to let it test how hard our wheel (ball) is instead of hardness of the concrete ...


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