Bicycle Mechanics - 2 inch tube with a 1.5 inch tire???

I am replacing my 26x1.95 MTB knobbies with 1.5 tires. I put the old 2" tube in the new 1.5 tire. It took a long time and seemed impossible to work out every twist. When I got it on, a flat (probably)pinch, developed. Should I be using a thinner tube? What size? I used the old tube b/c a "tech" guy from Performance told me I could as long as my tire was 1.5 or higher.....Thanks in advance........

The only problem that I can see is that it's a PITA to stuff a fat inner tube into a skinny tire. If you aren't careful enough you'll pinch a section of tube under the tire bead and eventually puncture your inner tube. Then you have to go through the whole process all over again.

It's best to use the correct size inner tube - the range is printed on the box. Given the choice, I'd prefer to use a slightly too small tube rather than one that's too big. In a pinch I'll use whatever I can find on hand.

I did the same tire switch. The tubes can accomodate 1.5 to 2.125 tires. I now run 1.5 Armadillos with these tubes. Are you partially inflating the tube before stuffing it in the tire? This makes it alot easier than trying un-twist a flopping piece of rubber. Try it. Once the far-side bead is in the rim, deflate the tube and be careful when you push, or lever the near-side on. It should work.

NOTE: Avoid the temptation to "run" the tire lever to seat the last bit of bead. That's where you will pinch the tube.

also whenever possible, try to put your tire back on without any tools...it will also give your fingers and wrist a good workout

Can you put your size 9 foot into a size 7 shoe?
Same logic . . .

Can you put your size 9 foot into a size 7 shoe?
Same logic . . .
Not really. Your foot doesn't flex and expand to a wide range of sizes, b/c it's size is constrained by bone. No such problem for a tire. There's still a logic, and it'd generally have you not putting 2" tubes in a 1.5" tire, but it ain't much comparable to feet and shoes.

Not really. Your foot doesn't flex and expand to a wide range of sizes, b/c it's size is constrained by bone. No such problem for a tire. There's still a logic, and it'd generally have you not putting 2" tubes in a 1.5" tire, but it ain't much comparable to feet and shoes.

All the tubes (5) I have bought over the last 8 months have been sized on the box 1.5" to 2.125". They seem to go in the 1.5" Armadillos just fine. Not like feet at all, for sure. The problem with my hands is arthritis so I have to use the spoons. Not so much with my Armadillo's but definitely with my English 3-speeds. Those 1-3/8th meats are tight!

I'll soon find out about the Trek 520. It has 700 X VERYSKINNY tires. Probably will change them to Armadillo 32's.