If you are skating 80 flat, the Endless 90s won't be less maneuverable IMO. The Endless 80 will be much more maneuverable than what you currently have, regardless of 80 or 84m wheels, because of the rocker. I'd go with the 90 personally, but I like the longer frames and don't do any low-speed cone/slalom stuff. Edit: agility = maneuverability. At my shop we grind three different types of ground beef: 80% lean ground chuck, 85% lean ground round, and 90% lean ground sirloin. Each type is made of trimmings from that specific primal cut. 80% lean ground chuck (shoulder) will be the juiciest and most flavorful. It's also the grind I recommend for making burgers for the grill. 100/80-17 90/90-17 Difference; Diameter inches (mm) 23.3 (591.8) 23.38 (593.8) 0.08 (2) 0.3%: Width inches (mm) 3.94 (100) 3.54 (90)-0.39 (-10) -10%: Circum. inches (mm) 73.2 (1859.19) 73.44 (1865.48) 0.25 (6.28) 0.3%: Sidewall Height inches (mm) 3.15 (80) 3.19 (81) 0.04 (1) 1.3%: Revolutions per mile (km) 865.61 (537.87) 862.7 (536.05)-2.92 90/90-R21 tires are 0.24 inches (6 mm) smaller in diameter than 120/70-R21 tires and the speedometer difference is 0.9%. In case of 80/100, it is 80 mm wide. And other people on Reddit itself said 2.75x18 and 80/100 have same width. They are just having different naming systems.----- I found these two tire naming in 2 different motorcycles (110 cc). Both had almost same specs. Just difference in tire specs: Pet insurance reimburses 70%, 80%, 90%, or even 100% of unexpected veterinary costs depending on your plan. Pawlicy Advisor is a free service that will help you find the best pet insurance for you - with a personalized recommendation and side-by-side comparisons. Questions & Answers. When I tried out the 90's vs.80's years ago I couldn't come to terms with the 90. The most noticeable difference to me was initiating "turn in" into corners. The 80 went where I pointed it and the 90 would stand the bike up making me have the feeling of falling off to the inside and dabbing my foot. 90/80-R12 tires are 1.42 inches (36 mm) smaller in diameter than 100/90-R12 tires and the speedometer difference is 7.4%. Golf ball compression ratings. The golf ball compression rating measures how hard or soft the ball is. The numbers range between a score of 30 and 120. The softest being 30, and the hardest is 120. Low compression golf balls are softer balls. Higher compression golf balls are harder balls. To put this into perspective, here are the numbers when you compare the Federal Premium .224 Valkyrie 90 grain SMKs to a comparable load in 6.5 Creedmoor at 1000 yards. Same deal with a 100 yard zero and 10 mph full value wind. 1000 Yards: .224 Valkyrie Vs. 6.5 Creedmoor 7GP9Yr.