Headshot Posted March 25, 2019 Posted March 25, 2019 Factually the commentators said Forster and Nino were running a 170tpi tyre. Less rubber in the high TPI casings but also overlaid plies so that presents a more convoluted pathway for a thorn or nail to penetrate.Most of the tyre issues stem from cuts and more rubber isn't going to stop the tyre from getting cut on sharp rocks. A stiffer thicker casing is going to be less compliant so its going to get cut more easily. You really want an infinity elastic tyre that is infinity tough.the reality is that a compromise needs to be made between those requirements That bold statement is nonsense IMO. The amount of tread and rubber ( among other things) is directly proportional to how easily a sidewall or tread area will be penetrated. These guys ( and you by the sound of it?) are riding tyres that in 29" weigh under 700g. Thats a pretty light and therefore thin, weak tyre. Add really low pressures and you have the recipe for flats. This thing with insterts is also all wrong. You run inserts to protect your rims, your tyres from pinch flats and to add some run flat ability. With the weight they add it would probably be better to run a heavier stronger tyre. especially if they make fixing a flat harder or don't actually provide any run flat ridability...
DieselnDust Posted March 25, 2019 Posted March 25, 2019 Yes, thicker casing is less compliant. That's the only correct thing in that highlighted area. Your previous argument (showing Enduro / DH pros "also puncturing") to prove your point is a foolish one. They ride faster & harder, on more demanding terrain and with more exacting demands of their tyres than the XC pro's do. If your story were true, they'd also be running Exo casings as "more rubber / stiffer casings don't improve puncture / cut protection". But no, they're all running at least DD / Super Gravity / Black Diamond / WCS Tough etc casings, and mostly DH casings. For extra puncture protection. Funny, that. As are the XCO pros on their trail bikes. Hmm. 170 TPI casings are available on some of the more "racy" tyres as an option. Increases conformity to the trail, reduces durability, weight & puncture protection. I thought they run the burlier casing for pinch flat protection since this is the most common reason for the DH and enduro bike tyre failures.Whereas with XCO bikes its more to do with failure on the treaded section of the tyre.
Headshot Posted March 25, 2019 Posted March 25, 2019 The other reason ( the major reason I think ?? ) with the pros puncturing a bit more than your normal weekend warrior is tyre pressure .In order for them to ride around corners and in single track at the speed they do ( and they really do go faaaast ! ) the guys have to ride their tyres at low pressure for more grip . And as with the thickness of the rubber - there is also a trade-off when it comes to low tyre pressure . Your sidewalls are a lot more exposed when your tyre is soft ( as anybody who has ever ridden 4x4 offroad in sand knows ) . Yes and no. The speed they ride has little to do with the pressures they use. In fact, higher speed requires greater tyre pressure to avoid side wall deflection and burping the tyre off a rim. The reason they need low pressure and more grip is because the tyres are horribly bald approximations of real off road tyres. Basically semi slick with some small side knobs. They are not conducive to grip or massive cornering speed, especially when run very soft. Its a trade off - they want light weight so the tyres are treadless and light. They want grip to compensate so they run low pressures. A perfect recipe for flats when ridden at the speeds these peeps go.
Captain Fastbastard Mayhem Posted March 25, 2019 Posted March 25, 2019 I thought they run the burlier casing for pinch flat protection since this is the most common reason for the DH and enduro bike tyre failures.Whereas with XCO bikes its more to do with failure on the treaded section of the tyre.And cuts, tears, lower pressure allowance, rim protection, grip, anti-roll and so on.
DieselnDust Posted March 25, 2019 Posted March 25, 2019 The other reason ( the major reason I think ?? ) with the pros puncturing a bit more than your normal weekend warrior is tyre pressure .In order for them to ride around corners and in single track at the speed they do ( and they really do go faaaast ! ) the guys have to ride their tyres at low pressure for more grip . And as with the thickness of the rubber - there is also a trade-off when it comes to low tyre pressure . Your sidewalls are a lot more exposed when your tyre is soft ( as anybody who has ever ridden 4x4 offroad in sand knows ) . I asked several mechanics what pressures their riders want. All are over 1.6 bar and up. They're not super low on the air pressure. On stages where there is a lot of sand they will drop the pressures (to 1.5 bar) and then your scenario comes into play. Underinflated tyres don't corner well at all. If we consider these guys weigh <70kg mostly then 1.5 bar isn't very soft even on a sandy course
V18 Posted March 25, 2019 Posted March 25, 2019 The winners of these events are the all or nothing type success rates. Few (no) punctures with uber wattage efficiency. Had schurter and them run heavier tyres it still wouldn't have resulted in no flats but it would have made them lose the benefit of controlling the bunch. Which is instrumental here in timing breakaway etc. They were VERY lucky they didn't have any more puncture than they did. But at that level. Everyone is k*kfiks and you need to push your luck to win. Trust me. I'm a dadduro specialist.
love2fly Posted March 25, 2019 Author Posted March 25, 2019 That bold statement is nonsense IMO. The amount of tread and rubber ( among other things) is directly proportional to how easily a sidewall or tread area will be penetrated. These guys ( and you by the sound of it?) are riding tyres that in 29" weigh under 700g. Thats a pretty light and therefore thin, weak tyre. Add really low pressures and you have the recipe for flats. This thing with insterts is also all wrong. You run inserts to protect your rims, your tyres from pinch flats and to add some run flat ability. With the weight they add it would probably be better to run a heavier stronger tyre. especially if they make fixing a flat harder or don't actually provide any run flat ridability... Mkes sense.....My thought on the inserts is that they add weight and hassle factor....and less air volume (and I understand wider rims = more air volume and can run lower pressures.)....I know this cos my damn rims are narrow!
PhilipV Posted March 25, 2019 Posted March 25, 2019 The winners of these events are the all or nothing type success rates. Few (no) punctures with uber wattage efficiency. Had schurter and them run heavier tyres it still wouldn't have resulted in no flats but it would have made them lose the benefit of controlling the bunch. Which is instrumental here in timing breakaway etc. They were VERY lucky they didn't have any more puncture than they did. But at that level. Everyone is k*kfiks and you need to push your luck to win. Trust me. I'm a dadduro specialist. You are giving way too much weight to the rotational weight issue. They'd still be controlling the bunch with 200gr per wheel additional rolling weight. 100gr if they removed the liner the cost them so much time and didn't do anything to prevent punctures.
T-Bob Posted March 25, 2019 Posted March 25, 2019 But as roadies found with their race for the widest tyre fad, once the width gets to a certain point it starts to negatively impact the aerodynamics and out weigh benefits of a wider tyre in terms of faster rolling resistance... not saying they are obsessed with marginal gains like out tar based brethren but they are all wearing aero road helmets and running light tyres for a reason.
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