GOOD QUESTION, OUR ASSUMPTIONS ARE MAINLY BASED ON OUR PERSONAL RIDING EXPERIENCE.  THE 25PSI IS SUGGESTED FOR THE LOWER END FOR OUR 650B TIRES WHILE 30PSI IS SUGGESTED AS THE LOWER END FOR 700C.  WE’RE BOTH AROUND 175LBS, ON MODERN WIDE RIMS, AND WE’VE RIDDEN FOR A LONG TIME AND USUALLY MAKE GOOD LINE CHOICES IN THE ROUGH STUFF.
OUR MAIN THOUGHT WITH PUTTING OUT PRESSURE RECOMMENDATIONS WAS TO DISCOURAGE PEOPLE FROM AIRING THEM TO THE STATED MAX PRESSURE THAT IS ON THE SIDEWALL WHICH IS, BELIEVE IT OR NOT, WHAT EVERYONE HAS BEEN TRAINED TO DO OVER THE YEARS BY THE BIKE INDUSTRY.  THERE ARE A LOT OF PEOPLE WHO ARE JUST DISCOVERING HIGHER VOLUME TIRES AND DON’T UNDERSTAND THE MAIN BENEFIT WHICH IS THE ABILITY TO RUN LOWER PRESSURE FOR IMPROVED GRIP, COMFORT AND SPEED.  UNFORTUNATELY, A LARGE VOLUME TIRE AIRED TOO HIGH IS VERY UNFUN SINCE THEY TEND TO BOUNCE OFF EVERYTHING AND CAN BE MORE PRONE TO FLATS FROM SIDEWALL SLASHES SINCE THE TIRE TREAD RESISTS DEFORMING OVER THE SHARP STUFF. WE’VE FOUND CHOOSING PRESSURE HAS A LOT TO DO WITH RIDER WEIGHT, RIM WIDTH, TERRAIN ETC, BUT PERSONAL HANDLING PREFERENCES, RIDING STYLE, AND EXPERIENCE ARE MASSIVE FACTORS AS WELL - WE TRY TO ENCOURAGE PEOPLE TO EXPERIMENT AND FIND WHAT WORKS BEST FOR THEM.  A LOT DEPENDS ON HOW YOU LIKE TO RIDE - ARE YOU TYPICALLY LATE ON THE BRAKES INTO CORNERS AND FIND YOURSELF IN TROUBLE, DO YOU PICK AGGRESSIVE LINES WHEN IT GETS SUPER ROUGH, OR DO YOU ANTICIPATE EARLY, CHOOSE SPEED CAREFULLY AND PICK DELIBERATE, OBSTACLE-FREE LINES…. IT ALSO DEPENDS ON WHAT YOU LIKE TO RIDE - ARE YOU RIDING SMOOTH, PACKED GRAVEL WITH FEW LOOSE TURNS OR ARE YOU TYPICALLY RIDING TWISTY SINGLETRACK OR VERY RUGGED 2TRACK?  
SO MANY FACTORS… I’VE KEPT LITTLE NOTES ON MY WORKBENCH OVER THE YEARS WITH THE PRESSURE I START OUT AT AND CONDITIONS, AND THEN WHAT I END UP WITH WHEN I FINISH A RIDE ALONG WITH WHAT TYPE OF TERRAIN I WAS ON. THAT WAY I HAVE A LITTLE REFERENCE IF I SPACE OUT ON WHAT TO AIR UP TO ON THE NEXT RIDE.  THE MAIN THING TO AVOID IS THE TIRE GETTING TOO SQUISHY THROUGH CORNERS WHICH IS USUALLY A PRECURSOR TO FOLDOVER - IF YOU NOTICE THE SQUISH JUST ADD A FEW PSI BACK IN.  USUALLY FOR ON-THE-FLY PRESSURE DROPS I BALLPARK IT BY DOING ONE QUICK TAP ON THE VALVE = .5 TO 1PSI.  WHEN YOU GET HOME MAKE A NOTE OF WHAT FELT GOOD.

OUR RACE CASING IS MORE DURABLE IN THE LARGER VOLUME SIZES, 27.5 X 2.2?? AND 650B X 47.99, IF YOU'RE RUNNING THOSE SIZES OF TIRES, YOU'LL BE SURPRISED BY THEIR DURABILITY AS LONG AS YOU RUN THE PROPER LOW PRESSURES.  THE NARROWER SIZES, 700C X 42, 38 AND ESPECIALLY THE 33S ARE FRAGILE AND REQUIRE EXTRA ATTENTION TO LINE CHOICE, PRESSURES AND MORE FREQUENT SEALANT TOP UPS.

ALL TUBELESS TIRES REQUIRE THE ENTIRE TUBELESS SYSTEM TO BE RELATIVELY AIRTIGHT TO WORK AT INSTALL.  IF YOUR NEW TIRES WON'T HOLD ENOUGH PRESSURE TO RIDE AFTER A FEW HOURS THEN THERE IS SOMETHING ELSE WRONG WITH THE SYSTEM - MOST LIKELY BEAD IS NOT PROPERLY SEATED, THE VALVE STEM NUT IS LOOSE OR LEAKING INSIDE AT THE VALVE HOLE OR THE RIM TAPE MAY NEED REPLACING OR ADDITIONAL LAYERS ADDED.  AND YES, WE'VE SEEN BRAND NEW WHEELS WITH FACTORY INSTALLED RIM TAPE THAT LEAKS AND NEEDS REPLACING IMMEDIATELY.

OUR EXPERIENCE RIDING LIGHTWEIGHT CASINGS ON ALL BRANDS OF TIRES (NOT JUST OUR OWN) OVER THE YEARS IS THAT SIDEWALL WEEPING IS VERY COMMON AND CAN BE ANNOYING FOR A RIDE OR TWO ONCE IT SHOWS UP AND IT MIGHT BE NECESSARY TO ADD AIR BEFORE RIDES, BUT THAT USUALLY SOLVES IT.  THE SEALANT DOES IT’S THING AND FILLS THOSE TINY PINHOLES AND THEY HOLD AIR.  BEST PRACTICE IS TO LET THE SEALANT BEAD OUT A BIT SO THAT IT SEALS AND DON’T BOTHER WIPING IT CLEAN FOR A FEW RIDES SO IT ALL SETS UP.  IF YOU CONTINUE TO SCRUB THAT SEALANT OFF THE OUTSIDE OF THE SIDEWALL IT’LL TAKE LONGER FOR IT TO SEAL.

THIS WEEPING CAN OCCUR FOR A NUMBER OF REASONS, GENERALLY AS THE TIRES AGE THE THIN RUBBER MEMBRANE ON THE OUTSIDE OF THE CASING WILL FATIGUE FROM THE STRESS OF FLEXING (IT’S WHY THE REAR USUALLY SHOWS THIS FIRST AS IT’S CARRYING THE BULK OF THE RIDER’S WEIGHT).  ONCE THIS HAPPENS… AND IT HAPPENS AT DIFFERENT TIMES DEPENDING ON HOW THE TIRES ARE RIDDEN AND THE THICKNESS OF THE CASING… THEY WILL WEEP OCCASIONALLY DUE TO EXTREME CHANGES IN TEMPERATURE, AFTER A GOOD SCRUBBING, OR VARIOUS OTHER BIZARRE SCENARIOS- BUT THEY ARE SAFE TO RIDE AND FRESH SEALANT INSTALL USUALLY FIXES IT.

EVERY SEALANT BRAND ON THE MARKET RECOMMENDS FRESH SEALANT ADDED TO THE SYSTEM EVERY 1 - 3 MONTHS - THE LIQUID COMPONENT EVAPORATES DEPENDING ON WEATHER CONDITIONS, AMOUNT RIDDEN (IF YOU PUNCTURE A LOT) ETC.ETC….  AND THIN CASING TIRES OFTEN GO DRY FASTER.

YES, ONE OF THE INGREDIENTS COMMON IN ALL TUBELESS SEALANTS IS A PH ADJUSTER WHICH KEEPS THE LATEX FROM COAGULATING ON THE SHELF.  ONCE THE SEALANT IS INSTALLED IT TENDS TO EVAPORATE THROUGH THE CASING AND IS NOTICEABLE AS A LITTLE WEEPING.  OUR JFF AND RACE CASINGS ARE VERY THIN AND THIS CAN BE MORE NOTICEABLE THAN ON THICKER SIDEWALLED TIRES YOU'RE USED TO.  THESE PINHOLES SEAL AFTER ONE RIDE AND ARE NOT AN ISSUE ALTHOUGH MOST SEALANT BRANDS RECOMMEND YOU TOP UP A LITTLE BIT OF SEALANT AFTER THAT FIRST RIDE.  WE ENCOURAGE YOU TO EXPLORE THESEALANT FAQSOR FORUMS REGARDING LIGHT CASING TIRES FOR MORE DETAILED INFO OR TO NERD OUT. 

WE WILL PROCESS YOUR ONLINE ORDER WITHIN 24-36 HOURS GIVEN ALL ITEMS ARE IN STOCK. WE STRIVE TO KEEP OUR WEBSITE’S INVENTORY UPDATED AT ALL TIMES, BUT ITEM AVAILABILITY IS NOT GUARANTEED. IF AN ITEM IS SOLD OUT, YOU WILL BE NOTIFIED VIA EMAIL OR TELEPHONE. ORDERS WITH SOLD OUT ITEMS WILL BE REFUNDED, OR THE AMOUNT OF THAT ITEM WILL BE CREDITED BACK TO THE ORIGINAL CARD, AND THE ORDER WILL BE SENT PARTIALLY FULFILLED, PER THE CUSTOMER’S WISHES. ORDERS ARE SHIPPED VIA USPS, UPS OR DHL EXPRESS. PLEASE BE SURE YOUR DELIVERY ADDRESS IS SECURE - ULTRADYNAMICO IS NOT RESPONSIBLE FOR PACKAGES AFTER THEY ARE DELIVERED TO THE REQUESTED ADDRESS. EXPEDITED ORDERS RECEIVED AFTER 1PM PST WILL SHIP THE FOLLOWING DAY. OVERNIGHT ORDERS RECEIVED BEFORE 1PM FRIDAY WILL NOT ARRIVE UNTIL MONDAY.

WE HOPE YOU LOVE YOUR PURCHASE FROM ULTRADYNAMICO, HOWEVER, IF YOU ARE NOT SATISFIED PLEASE EMAILHELLO@ULTRADYNAMICO.COM AND WE WILL SEND YOU RETURN / REFUND INSTRUCTIONS. PLEASE DO NOT MAIL ANY ITEMS BEFORE CONTACTING US.ITEMS PURCHASED FROM ULTRADYNAMICO MAY BE RETURNED FOR REFUND ONLY WITHIN 14 DAYS OF RECEIPT OF ITEMS PROVIDED THEY ARE IN THEIR ORIGINAL CONDITION, UNUSED AND UNMOUNTED. ALL DISCOUNTED ITEMS ARE FINAL SALE - THEY MAY NOT BE RETURNED.ALL SHIPPING FEES ARE NON-REFUNDABLE UNLESS PRODUCT IS DETERMINED TO BE DEFECTIVE OR DAMAGED. WE RECOMMEND MAILING YOUR RETURN WITH TRACKING AND INSURING THE PACKAGE.RETURN SHIPPING COSTS ARE THE RESPONSIBILITY OF THE CUSTOMER. ULTRADYNAMICO DOES NOT SUPPLY RETURN LABLES OR COVER RETURN COSTS.ULTRADYNAMICO IS NOT RESPONSIBLE IF THE RETURNED PACKAGE IS LOST OR THE ITEM DAMAGED IN THE MAIL.IF YOUR ORDER IS DAMAGED, PLEASE KEEP ALL ORIGINAL PACKAGING AND CONTACT US RIGHT AWAY. ANY DAMAGE TO A RECEIVED SHIPMENT MUST BE REPORTED UPON RECEIPT.NO DAMAGE CLAIMS WILL BE ACCEPTED AFTER 7 DAYS PAST DELIVERY. 

ULTRADYNAMICO SHIPS INTERNATIONALLY TO CANADA, EUROPE, AUSTRALIA, NEW ZEALAND, JAPAN AND VARIOUS OTHER FARAWAY PLACES.  IF YOUR INTERNATIONAL ADDRESS ISN’T ACCEPTED AT CHECKOUT IT’S PROBABLY BECAUSE WE DON’T TYPICALLY SHIP TO YOUR LOCATION BECAUSE IT’S TOO EXPENSIVE / RISKY, BUT IF YOU’D LIKE TO RECEIVE A SHIPPING QUOTE ANYWAY, PLEASE EMAILHELLO@ULTRADYNAMICO.COM  WITH THE ITEMS AND QUANTITIES YOU’D LIKE TO PURCHASE AS WELL AS YOUR EXACT ADDRESS AND PHONE NUMBER.  
YOU WILL THEN RECEIVE A SHIPPING QUOTE AND A PAYMENT OPTION.  ONCE PAYMENT HAS BEEN MADE AND YOUR PACKAGE SHIPS YOU WILL RECEIVE AN EMAIL CONFIRMATION WHICH INCLUDES ALL PERTINENT TRACKING INFORMATION.  
PLEASE BE AWARE ALL INTERNATIONAL ORDERS OF THIS NATURE ARE SHIPPED VIA DHL EXPRESS OR USPS INTERNATIONAL PRIORITY MAIL AND GENERALLY TAKE 6-12 BUSINESS DAYS.  WE HIGHLY RECOMMEND DHL EXPRESS AS THEY HAVE BEEN THE MOST RELIABLE IN THE LAST FEW YEARS.
ALL INTERNATIONAL SALES ARE FINAL- RETURNS ARE NOT ACCEPTED ON INTERNATIONAL SALES.  
ULTRADYNAMICO IS NOT RESPONSIBLE FOR IMPORT FEES, TAXES, VATS OR ANY OTHER CUSTOMS FEES SHOULD YOUR PACKAGE BE PROCESSED BY CUSTOMS. FEES CAN RANGE FROM 20% TO 40% OF THE ORDER TOTAL.  ALSO, BE AWARE IF CUSTOMS DOES PROCESS YOUR SHIPMENT YOU MAY EXPERIENCE DELAYS.  IF PACKAGES ARE REFUSED DUE TO UNEXPECTED CUSTOMS CHARGES YOU WILL BE CHARGED FOR OUTGOING AND INCOMING SHIPPING CHARGES AS WELL AS THE REFUSAL CHARGES.  UNFORTUNATELY WE HAVE NO CONTROL OVER THESE CHARGES OR DELAYS AND CANNOT PREDICT WHAT THEY MIGHT BE, AND THEREFORE SUGGEST YOU CONTACT YOUR LOCAL CUSTOMS OFFICE FOR ADDITIONAL INFORMATION.  THANKS FOR YOUR UNDERSTANDING.

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