I'm restoring my 1975 Motobecane Gran Touring 10 speed
which I haven't ridden for a few years.
I've replaced the two original michelin 27x1.25" tires which were very worn and since hardened to unusability. Very hard to get off they were so stiff.
Also replaced the inner tubes.
One wheel holds 60-70 psi but the rear does not, leaking off to flat within a day.
I removed the tire and the tube, checking the tube mildly inflated in a tub of water squeezing it for all I could but did not see a stream of bubbles. So
I replaced it with another tube and it was OK for a day but also leaked off to completely flat.
While its been a while, I've mounted many tires and tubes before on this and other bikes and never had this problem.
If its leaking, it has to be leaking from the tube, how else could it escape? THe tube is held from bursting by the tires which are properly mounted to the bead in the alloy wheels.
Have I missed something?
PS it also has new helmet, new LED head and taillights, and a trip computer. Forgot the brake pads, they are coming next week.
which I haven't ridden for a few years.
I've replaced the two original michelin 27x1.25" tires which were very worn and since hardened to unusability. Very hard to get off they were so stiff.
Also replaced the inner tubes.
One wheel holds 60-70 psi but the rear does not, leaking off to flat within a day.
I removed the tire and the tube, checking the tube mildly inflated in a tub of water squeezing it for all I could but did not see a stream of bubbles. So
I replaced it with another tube and it was OK for a day but also leaked off to completely flat.
- I used correct tire irons to mount the tire so no pinching of the tube
- I checked the inner part of the tire and the rim to make sure there were no sharp objects or splinters
- I carefully mounted the stem to be perfectly perpendicular to the rim where it pokes through
- I also checked and in place is the rubber strip that is placed over the ends of the spokes to protect the tube.
- I made sure that the Schrader valve insert was tightly screwed into the valve stem.
While its been a while, I've mounted many tires and tubes before on this and other bikes and never had this problem.
If its leaking, it has to be leaking from the tube, how else could it escape? THe tube is held from bursting by the tires which are properly mounted to the bead in the alloy wheels.
Have I missed something?
PS it also has new helmet, new LED head and taillights, and a trip computer. Forgot the brake pads, they are coming next week.
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