You / he might consider using a slightly bigger size like 90/90 - 10
https://www.amazon.com/Michelin-S1-Urba ... B005J87U6KThe site below gives you the dimensional difference between tire sizes
https://www.tacomaworld.com/tirecalc?ti ... 0-90-90r10 90/70-10 90/90-10 Difference
Diameter inches (mm) 14.96 (380) ..... 16.38 (416)..... 1.42 (36) 9.5%
Width inches (mm) 3.54 (90)..... 3.54 (90)..... 0 (0) 0%
Circum. inches (mm) 47 (1193.81).... 51.45 (1306.9).... 4.45 (113.1) 9.5%
So the 90/90 is just slightly bigger in dia by 1.42 inches ...which would put your bum approx 3/4" higher from the ground.
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