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If it were just £ then they wouldn't give a tape at all - they are not obliged to. To give one that doesn't do the job invites bad image and negatively impacts on their sales [as in this thread]. The staggerd placement of the nipple clearance holes is the root cause of the problem. I tried wider rim tapes but they foul the tyre beads - if they get stuck under the bead then the tyre won't run true - if they get nudged by the tyre beads then back to square one with a clearance hole edge exposed.
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The well of the rim is basically flat, each side of the well there is a slightly raised bead seat. The job of a rim tape is to completely cover the spoke holes in the well, when a spoke hole leaves no horizontal rim material on the outside edge then the rim tape cannot do the job of resisting the tube pressure. I never said that all Miche Pistard rims exhibit this fault, nor am I bad mouthing them, I use their chainsets and sprockets. I was a machine tool engineer and I have a degree in mechanical engineering, both of my wheels and the one at the velodrome yesterday had this problem. If the rim tape cannot fully cover the hole and sit in the well then you will get this problem. The rim tape must sit below the bead seat level else the tyre will dislodge it when the beads move onto the bead seats as it is pumped up. The most likely cause of this is the use of a dual diameter drill in a single operation [to reduce time and manufacturing costs] rather than first drilling the large holes radially at right angles to the well and then going round again with the small diameter drill and at the angle if the spokes.
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I had a pair of Miche Pistard wheels for my first velodrome bike. After suffering a total of 7 punctures from both wheels always on the inside of the tube and regardless of trying different ( and even two) rim tapes I could see that the root cause was a manufacturing fault that was not rectifiable. The fault is that the holes drilled in the base of the rim (for the insertion of the spoke nipples) are staggered to the point that some actually nick the sides of the bead seats and thus cannot be fully covered by a rim tape, leaving a small uncovered crescent with a sharp edge. Apply some pressure and the inner tube will find the exposed crescent and its edge bursts the tube. All of us who have experienced this have tried different rim tapes and (wrongly) thought that they may have pinched the inner tube. I personally had a rear wheel puncture when I was about to get on the bike at the velodrome and witnessed a front go this morning at Derby Velodrome - the rider pumped up his tyres and sat down awaiting the start of the session, minutes later the front wheel punctured right next to us. When we removed the tyre it was exactly as described above. After 6 months of problems I’d had enough and took my wheels back to Halfords who, readily agreed that the problem was indeed a manufacturing fault and made a full refund on the spot. I switched to tubulars which don’t come off the rims if they puncture on the banking. The mechanic at the velodrome told me that they had seen this problem a number of times with these rims. There is no way I would ride these wheels on the velodrome and the greater concern is that someone riding them will puncture and involve you in a crash. Remarkably, none of the punctures I experienced actually happened on the boards.
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Yes at 64 I'm now accredited on the Velodrome at derby ( 48 years since I rode the track as a teenager). I have Campagnolo Pista wheels and Vittoria Pista EVO CL tubs held on with Vittoria Magic Mastik. Watch the video on Vittoria's site - it's soooo easy to use this glue. The banking on the velodrome is 42 degrees so (unless you are going at high speed) most of the time you are riding on the side of the tyre, which is a serious test of the glue and is seems to have no problem. Indeed, after a 2 hour session, the tubulars appear to have started to roll round due to them having all the load and grip on the banking side ( not on the crown of the tyre), but on inspection the base tapes are always equally visible on both sides and the clear glue fillet is intact. What is actually happening is that the during the 2 hour session, the stresses are streaching the sidewall on the left and compressing the sidewall threads on the right (banking side) and its testimony to the Magic Mastik that it has no problem resisting these forces. And it's reassuring to see that within a short time of leaving the track, the tubular sidewall stresses even out and the tread and returns to the correct centralised position. The bottom line is that I have complete trust in the Magic Mastik. Also it's a dream to use; one coat only; put tthe tub straight on with the glue liquid; and no sidewall mess. It should also be noted that all Uk velodrome websites say that tubs are to be glued on and that tub tape should NOT be used on the velodrome.
No you are correct [my mistake]. Miche was founded by Ferdinando Michelin in 1919 [see https://www.miche.it/en/azienda & http://www.miche.it/en/azienda/chi-siamo ] and they originally traded under that name until the French Michelin company got upset and caused them to change their trading name.