Fitting Tubulars
TummyBanana
Posts: 7
fitting Tubulars, one question How?
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Comments
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I do it as follows.
1) If it is a brand new tub, put a bit of air in it, stretch the tyre a little, usually by puttig one foot on it and pulling up with my hands.
2) Glue the rim, if it is abrand new wheel I think you can rought the surface a little
3) Insert valve through hole and fit tyre over rim, ensuring it is centred
4) Inflate to about 80 psi and leave to dry (overnight)
5) Fully inflate and ride
They are a bit of a struggle first time, but like anything it becomes easier.
I am sure other tub users will have variances to the above0 -
It is easier if you mount it on a dry rim and pump it to full pressure first, leaving it for a few days to stretch before you glue it on.0
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For road use i would do the same to stretch the tyre as suggested above, then use tub tape to stick it to rim.
This is cleaner than gluing
For track use, I glue the rim (if clean) and leave for 24 hrs.
glue again and leave again for 24 hrs.
Then glue tyre and leave for about 20 mins to get tacky then fit to rim.0 -
Agree..............the best way to stretch a new tub so that it's not quite so difficult to fit when the tape/glue is in place is to fit dry and pump up nice and hard and allow to stand for a few days.Smokin Joe wrote:It is easier if you mount it on a dry rim and pump it to full pressure first, leaving it for a few days to stretch before you glue it on.0 -
oldwelshman wrote:For road use i would do the same to stretch the tyre as suggested above, then use tub tape to stick it to rim.
This is cleaner than gluing
There is a bit of a debate on Weight Weenies, but apparently tub tape increases the rolling resistance of the tyre. I have no idea why though.0 -
Not sure how tub tape below the tyre would increase the rolling difference.
How woukd they know anyway
You would have to do testing with the exact same wheel with and without tape, in exactly the same conditions.
debatable me thinks
Anyway if I was using tubs in the road I would use tape as it is far cleaner and easier to use and cannot believe the performance is anything but miniscule and not worth worrying about.0 -
The reason that tub tape is supposed to offer increased rolling resistance is losses due to hysteresis i.e. energy lost due to the tyre moving around on the rim - with glue you only have one 'boundary' layer whereas with tape you have two and some micro-movements of the tape substrate. TBH it's going to be pretty neglibile in the greater scheme of things. It might be important for things like track pursuits and hour records, but for the normal rider, it probably pales into insignificance. For me, it's about convenience and confidence - Tufo Extreme sticks well, is relatively easy to remove and doesn't require solvents to clean off the rim.Make mine an Italian, with Campagnolo on the side..0
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Tubs don't roll as well as clinchers because the tyre is sitting on a cushion of adhesive and this allows it to float on the rim slightly as it rotates. This is more pronounced with tape than with glue as the tape is thicker. The effect is fairly minimal however, and the pay off is a lighter rim/tyre combination which gives livelier acceleration.0
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Sorry Monty, you beat me to it!0
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If this is caused by hysteresis surely it would only have an effect on the first rev of the wheel?
This would be the same as slip in induction motors, even though the stator field and rotor rotate at same speed? 0 -
also if it was that bad wouldn't the valve snap off? 8)0
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Here's another vote for Tufo tape.
I have also become quite fond of Tufo tubular clinchers. I'm no racer anymore
but they do the job for me. However I'm sure someone will write in telling us all
what junk they are. Quess that's why they call this a forum.
Dennis Noward0 -
It might be important for things like track pursuits and hour records, but for the normal rider, it probably pales into insignificance.
I am also pretty sure they would not be happy if you rode on a velodrome on tub tape .0
