How much can i mismatch tube & tyre diameter?

[Tallpaul]

What do you reckon is the maximum tyre size i can run using 1.5 - 1.7 tubes?

 

[king-salsa]

you could run a 2.1 but i would not risk it the tube gets very thin ! if your trying to get super light tubes the maxxis fly tubes are the best allround for light and good tyre filling

 

[m1kesmith]

i use 1.25-1.5 " tubes on both bikes.. from 1.25 city runners to 2.1" knobblies. I'm sure i used the same on my 2.5" ground control extreme.

 

[Tallpaul]

1.25-1.5 " tubes on 2.5" ground control extreme.

:shock:

Then my toying with running them on a 1.95 is utterly conservative

 

[m1kesmith]

i just find it easier to buy one size of tube, and if you've ever tried fitting 2" tubes in a 1.25" tyre you know why i err on the small size

 

[Tallpaul]

i just find it easier to buy one size of tube, and if you've ever tried fitting 2" tubes in a 1.25" tyre you know why i err on the small size

Yup, i bought a job lot of Ritchey 1.5 - 1.7's on the cheap, so i just want to see if i can use them in my whole fleet

 

[king-salsa]

1.95 should be ok with a 1.7 tube but it depends some tubes we have at work are tiny when inflated some are masif depends on the brand

 

[Pickle]

I ran a 1.95 tube for 1 ride on a 2.3 tyre, no problems. Did worry about it for most of the ride though, as it was a cheapy Halfords own tube

 

[jonboy]

When I used to race XC, I had a set of wheels with 1.7 Ritchey Z Max tyres (in the red tread colour). I used to run the 26 x 1" specialized tubes designed for their mtb diameter slicks in them, when courses were smooth enough to allow.

They needed to be inflated a little on the firm side to avoid pinch punctures, and would go down pretty quick if you got a large thorn in the tyre, but hey, BITD it was all about weight..... ...and they weighed nothing!!!!

 

[Mr. Zero]

i use 1.25-1.5 " tubes on both bikes.. from 1.25 city runners to 2.1" knobblies.

I do the same: 1.25" tubes in 2.1 tires. I have no increased frequency of flats and I live in the American Southwest where there are plenty of jagged rocks and pesky thorns laying in wait.