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DieselnDust

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  1. 100% that is what I am doing this year
  2. Frame clearance and then brake caliper reach is the key problem with fitting 32mm tyres to a rim brake frame. long reach calipers are necessary
  3. SRAM brakes developed due to leaps and bounds of the erratically funcytioning taper bore brakes of the mid to late 2000’s. Once they stopped trying to reinvent the wheel (stopper) their brakes actually worked very very well. I still have Guides with revised lever internals that are strong and reliable
  4. Last year some people got reseeding letters after their first seeding letter. I suspect the same will happen this year to keep interest in the PPA road race calendar till ctct
  5. All valid points that need to be answered by the event organiser. sitting in my ivory tower I’m smug that I didn’t race to face all this pooh. 99er didn’t have the crashing problem but we certainly provided some dress rehearsals for a perfect execution at TDPPA
  6. Great question!! In mineral oil, water has to be entrained in the oil. These oils have an affinity to absorb water but when heated will release that water more easily than a glycol (DoT oils) Boiling point is not so much the issue but rather bulk modulus. We refer to boiling point because there a correlation to bulk modulus. Liquids are generally considered as incompressible right…, but that’s at room temperature. Get a liquid close to its boiling point its bulk modulus changes and it can then be compressed. When it boils it’s a gas and gas bubbles are compressible. so we accept that hydraulic oils absorb water. In many large hydraulic systems we fill fit filters and coalesces to know the dirt and water out to very low parts per million levels. There’s no such luxury in a vehicles braking system so we need an expansion chamber to allow for fluid expansion at temperature and also an oil that can hold onto water molecules so that they behave as fishery have a higher boiling point. To do this the water molecules have to be separated from each other and bonded to the oil or something in the oil. Glycols do this quite effectively which is why they are used in brake fluids in all machines. Mineral oils have limited capacity to do this because it’s achieved through a small dose of emulsifying additives. Can’t have to much because water emulsions have bulk modulus problems ( will need a big expansion chamber). so to answer why does the lever feel squishy? Generally this won’t happen during braking. A hit brake will often suffer face due to either pad material overheating and friction reducing, or due to fluid boiling and gas bubbles compressing because of excess water in the oil. Even at small quantities, water that isn’t bound to the emulsion additive in mineral oils will boil due to pressure and temperature from the braking and pressure. Remember under pressure the water won’t boil at 100C, it will boil at a higher temperature but this is still lower than the surrounding oil or glycol.
  7. I’m not seeded yet. Corporate entry which has not been completed yet. if you seeded you’re seeded. But there will be people requesting reseeding which might fill those racing groups. maybe they lock seeding and don’t allow reseeding.
  8. its going to be very interesting. I'll get bumped down to 1A while "&" will be filled with C riders so its going to be interesting.... very interesting
  9. I recognise a few of the newbie names and I feel sorry for them. Burnt out legs by Edinburgh.... I hope they're sensible
  10. This is why I seldom race on the road anymore. So so risky
  11. The seeding is now a mess. The group minimum for A has shifted to 11.99 so I got bumped down a group. im not terribly interested in doing anything about it but it does mean im less excited about CTCT as this is going to create a bit of havoc with the groups if people now get reseeded for ctct
  12. Not sure what ls going on here in bold. Very confusing. I think you mean mineral. DoT absorbs water but its reflux boiling point is still much higher than mineral or water. Think of engine coolant, ethylene glycol, it raises the waters boiling point to prevent overheating and pump cavitation. DoT has a similar property. Mineral has to do the same but it’s not as good at it
  13. No but I will tell you this in 2008 cape epic day 3 stage 2 coming down the gamkaberg toward calitzdorp spa my team is had a bit of brake failure. He’s XT’s brake fluid boiled. He then only had the fronts. Had to get a walk parts of that descent. we don’t often experience that but the Hope brake systems didn’t have any issues. Magura and Shimano struggled. Both were mineral oil while Hope was DoT.
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