Originally Posted by
hokiefyd
That's a good point. If going down to 28mm, then you may consider different inner tubes. Just have a look at your current ones -- they'll have a size printed on them in white(ish) paint, probably near the valve stem. Sizes are often listed as a range...it may say something like "700 x 35-45mm" or something similar. In that case, the tube is best used in a 35-45mm tire, and I'd probably buy a smaller tube (perhaps something labeled for a 25-35mm tire) if downsizing. If your current tubes say something like "30-40mm" then you may be okay. You just want to avoid having too much rubber material inside the tire which can then get bunched up when you install the tire. In general, I would err to the smaller size for tubes (ie: use a 25mm tube for 28-30mm tires, etc.).
...and then there is a question should I get an inner tube with a presta or shrader valve? I have Shrader valve on my current trek fx2 hybrid and I think the rims were drilled for shrader....
so this means I should put an inner tube in there that has a shrader valve...but I was reading presta valves are for higher air pressure that road tires need and shrader valves cant get that higher air pressure...so if I put 28mm tires on there that require 100 psi with inner tubes with shrader valves does this mean I wont be able to inflate to the required 100 psi?
I shouldnt put a presta valve in my rim if it was drilled wider for the shrader valve?