Hi, I'm going to get some narrower 26x1.75 tires and want to ask if it'll be ok if I used my old tubes. However, my tubes are Maxxis Ultralights which were designed for 1.90"-2.125" tires. I know using too small a tube can over-stretch it making the tube too thin, but in this case, I will be doing the exact opposite. I know getting a new tube isn't very expensive, but I've already got these tubes and they are also quite light at 125g each. So will they work? Thanks.
actually i have found that by using tubes that are one size bigger than the tires they hold air far longer. i think what happens is that the butyl rubber in the tube does not stretch as much thereby not letting as much air out. all tubes emit air through the rubber eventually. that is why we have to refill from time to time. i don't race so the extra weight is not a factor.