kardar2

Hello,
Okay I have read on the forum to run slicks. I ride a MTB to work this fall I will be putting on new rubber. My thinking is if I ride Nobbies the Nobbies gives added protection with glass and sharp objects. Isn't slicks a lot thinner. I have Kevlar tires now. So is my thinking wrong. Thanks

ThermionicScott 

That might be true, but slicks are so much nicer to ride on pavement that I'll take my chances. A big part of avoiding flats is to watch where you're going, and get off the saddle when you're going over bumps.

Sawtooth

Interesting question....I don't think I get more flats with slicks than with knobbies, but I hardly ever run knobbies. Most of what flats my slicks would also certainly flat my knobbies (huge goat heads, cotter pins, nails, staples, etc).

Kojak

There are also a lot of tires out there that are designed to minimize the potential for flats with thick, puncture resistant belts. Pretty much any major bicycle tire manufacturer makes a quality, extrememly puncture resistant commuting tire that is going to be a lot nicer to commute on as compared with a knobby.

Seattle Forrest

Knobbies don't stop as well as slicks, on pavement, because they have less contact with the ground. That would be enough reason for me, but, honestly, if you try them out, you'll "feel" everything you need to know.

Knobby tires are for dirt; slicks are for pavement.

Chesha Neko

I would expect the opposite. I think knobbies and tread give glass and other stuff more opportunity to stick to the tire and cause a tear or puncture. A slick tire is IMO always the best bet on the road, and as others have said you can get smooth tires with anti-puncture belts.

Kojak

Knobs do hold the vulnerable part of the tire (the casing) off the ground, so the theory is legitimate, but as Seattle Forrest pointed out, a knobby has very limited grip and adhesion on pavement so as a matter of safety, using a road tire on pavement will provide a better experience and safer travel than a knobby will.

KonAaron Snake 

Knobbies also are more prone to collecting debris, which can work its way through the tire. I get fewer flats with slicks...and the performance issues have been discussed.

graytotoro

I rode over a thumbtack on the weekend. Lodged all the way in...the knobbly part of the knobbly tire. Just missed the tube.

Also, on a related note, is it considered bad to run a bigger tube on a narrower tire? I've got a 1.5-2" tube and am thinking about getting a 1.25" tire.

Kojak

It's not a huge issue, just makes it more difficult to mount the tire without twisting or pinching the tube. This probably wouldn't work if your tire were any narrower.

Monster Pete

Tubes are fairly forgiving, and you'll get away with putting a smaller tube in a slightly too-big tyre (the tube expands a bit more to fit the space) or putting a larger tube in a smaller tyre, but fitting is more difficult. If you're somewhere around the borderline between two tube sizes, I'd recommend the slightly larger one.

chas58

Tube should be fine if you get it to fit. I have 20-25mm tubes in 35mm tires. I don’t think you will be able to fit a 2” tube in a 1.25” tire (I can’t).

There is all kinds of flat protection out there, from the thinner lighter Kevlar membrane, to the thicker heavier padding in the tire. Many good tire companies offer normal, medium, and heavy duty flat protection. I have some pretty big slices in some of my tire tread, but nothing that has gone through. Generally the only flats I have gotten are pinch flats (sharp corner with too much weight on the wheel and/or not enough air).

Knobbies are just going to slow you down, and offer minimal flat protection. It does work to a limited degree, but it isn’t the best way to protect yourself.